CN114195914B - Method and system device for producing chlorinated polypropylene - Google Patents

Abstract

The invention provides a method and a system device for producing chlorinated polypropylene, wherein the method comprises the following steps: the raw materials for producing the chlorinated polypropylene are simultaneously stirred and preheated by vortex and then mixed by supergravity to obtain micron-sized suspension of polypropylene particles; the micron-sized suspension reacts with chlorine to prepare chlorinated polypropylene. The system device comprises a vortex type stirring device with a heating device, a hypergravity mixing device and a chlorination device which are sequentially connected. The method has the advantages of simple and safe process flow and high utilization rate of chlorine, realizes the recovery of byproduct waste acid, greatly reduces the amount of waste water, and ensures the safety and stability of the device.

Description

Method and system device for producing chlorinated polypropylene

Technical Field

The invention relates to the technical field of chemical technology and equipment, in particular to the technical field of chlorinated polypropylene, and particularly relates to a method and a system device for producing chlorinated polypropylene.

Background

Chlorinated polypropylene resin (CPP) is a chemically modified product of polypropylene, has white or yellowish solid appearance, good wear resistance, aging resistance and acid resistance, and is widely applied to the aspects of paint, adhesive, printing ink, vehicle, leather treatment agent and the like. With the rapid development of chlorinated polypropylene resin, new application fields are being developed continuously, and the chlorinated polypropylene resin is a fine chemical product with high added value.

The synthetic method of the chlorinated polypropylene resin mainly comprises three different methods, namely a solid phase method, a solution method and a water phase method, and the synthetic method is the same as that of other chlorinated polyolefin.

The solid phase method is to add polypropylene solid and inert powder particles for preventing carbonization into a fixed fluidized bed reactor, and introduce chlorine into the fixed bed under the induction state of auxiliary ultraviolet light or elemental fluorine so as to cause chlorination reaction in the reaction bed, thereby obtaining the required chlorinated polypropylene product. The solid phase method has the advantages of simple process, less equipment corrosion, pure product, low production cost, no discharge of three wastes, and the like. However, the heterogeneous reaction is difficult to control in the chlorination process of the product, so that the chlorination is uneven, the reaction heat is difficult to remove, and the problems of coking, color change, bonding and the like are caused, so that the method is rarely adopted at present.

At present, the water phase suspension method is mainly adopted to produce the chlorinated polypropylene resin. The process of the aqueous suspension method is as follows: the polypropylene resin and the dispersant are added into a reaction kettle according to a certain proportion, and a proper amount of water is added, heated and stirred to enable the feed liquid to be in a suspension state. Chlorine is generally introduced at a temperature of 45-70 ℃ and under normal pressure, and chlorination is carried out under photoinitiation. And stopping introducing chlorine when the chlorination degree reaches a certain degree, and removing unreacted chlorine and substituted HCl. Precipitating the chlorinated solution with methanol, ethanol, acetone, etc., purifying the product, and finally washing, coating, drying, etc. to obtain polypropylene CPP product with chlorine content up to 65%.

The aqueous phase suspension method has the advantages of convenient operation, simple process and low production cost. The solubility, purity and the like of the product are superior to those of the solid phase method and the solution method, the three wastes are easy to treat, and the method is a green production process which is greatly developed at present. However, the aqueous phase suspension method has the defects that the method is corrosive to production equipment, water is used for replacing a solvent, heterogeneous reaction is carried out, and the chlorination uniformity of the product is insufficient due to the increase of the viscosity of reaction materials in the reaction process and the insufficient stirring strength, so that the further popularization and application of the aqueous phase suspension method are greatly limited.

Therefore, there is a need to develop an improved aqueous suspension process that facilitates the industrial application of the aqueous suspension process.

Disclosure of Invention

In view of the problems in the prior art, the invention provides a method and a system device for producing chlorinated polypropylene, wherein the method realizes the preparation of micron-sized suspension by adding substances such as surfactant and the like in an auxiliary way through vortex stirring with heating and super-gravity mixing, and solves the problem of insufficient chlorination uniformity in the prior art.

To achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides a process for producing chlorinated polypropylene, the process comprising:

the raw materials for producing the chlorinated polypropylene are stirred by vortex under the heating condition and then mixed by supergravity to obtain micron-sized suspension of polypropylene particles; the micron-sized suspension reacts with chlorine to prepare chlorinated polypropylene.

According to the method for producing chlorinated polypropylene, provided by the invention, the effects of polypropylene swelling and preliminary dispersion are simultaneously realized through vortex stirring, a primary suspension is obtained, and supergravity mixing is adopted in combination, so that solids in the suspension are reversely contacted with liquid in a curved duct at a great relative speed under the conditions of high dispersion, high turbulence, strong mixing and interface rapid updating, and materials are fully mixed, so that a relatively stable micron-sized suspension is finally obtained; the method can be operated continuously, and is beneficial to industrialized mass production.

The micron-sized suspension according to the present invention refers to a suspension in which microparticles are stably present in an aqueous solution. The microparticles may have a particle diameter of 50 to 200. Mu.m, for example, 50 μm, 60 μm, 80 μm, 100 μm, 120 μm, 140 μm, 150 μm, 180 μm or 200 μm. The micron-sized suspension liquid obtained by the invention does not generate sedimentation in the conveying process, and the system is uniform.

Preferably, the raw materials for producing the chlorinated polypropylene comprise polypropylene, water, a surfactant, an initiator and a dispersing agent.

The invention further preferably adopts a surfactant, an initiator and a dispersing agent to disperse the polypropylene, and has the swelling function, so that the chlorination reaction efficiency is improved and the uniform dispersion is realized.

Preferably, the polypropylene has a particle size of 200 μm or less, and may be 200 μm, 180 μm, 160 μm, 150 μm, 100 μm, 80 μm or the like, for example.

Preferably, the mass ratio of the polypropylene to the water is 0.03-0.05:1, for example, 0.03:1, 0.033:1, 0.035:1, 0.037:1, 0.039:1, 0.042:1, 0.044:1, 0.046:1, 0.048:1, 0.05:1 or the like.

Preferably, the mass ratio of the surfactant to the water is 0.5-1.2:1000, for example, 0.5:1000, 0.58:1000, 0.66:1000, 0.74:1000, 0.82:1000, 0.89:1000, 0.97:1000, 1.05:1000, 1.13:1000, or 1.2:1000, etc.

Preferably, the mass ratio of the initiator to the water is 0.6-1.2:1000, for example, 0.6:1000, 0.67:1000, 0.74:1000, 0.8:1000, 0.87:1000, 0.94:1000, 1:1000, 1.07:1000, 1.14:1000 or 1.2:1000, etc.

Preferably, the mass ratio of the dispersant to the water is 0.8-2:1000, for example, 0.8:1000, 1:1000, 1.1:1000, 1.2:1000, 1.4:1000, 1.5:1000, 1.6:1000, 1.8:1000, 1.9:1000 or 2:1000, etc.

The invention further preferably achieves better dispersing and swelling effects through the proportion.

Preferably, the surfactant comprises a polyoxyethylene fatty alcohol and/or a polyoxyethylene alkylphenol.

Preferably, the dispersant comprises sodium polymethacrylate and/or sodium dodecylbenzene sulfonate.

Preferably, the initiator comprises benzoyl peroxide and/or azobisisobutyronitrile.

The invention further preferably selects the substances, and the substances are mutually matched, so that the polypropylene dispersion is facilitated.

Preferably, the vortex stirring and preheating are performed in a vortex stirring device with a heating device.

Preferably, the rotational speed of the vortex stirring is 300-600 r/min, for example, 300r/min, 350r/min, 400r/min, 450r/min, 500r/min, 550r/min, 600r/min or the like.

Preferably, the heating temperature is 50 to 80 ℃, and may be, for example, 50 ℃, 54 ℃, 57 ℃,60 ℃, 64 ℃, 67 ℃,70 ℃, 74 ℃, 77 ℃, 80 ℃, or the like.

Preferably, the rotation speed of the super-gravity mixing is 200-500 r/min, for example, 200r/min, 234r/min, 267r/min, 300r/min, 334r/min, 367r/min, 400r/min, 434r/min, 467r/min or 500r/min and the like can be adopted.

Preferably, the temperature of the supergravity mixing is 50 to 80 ℃, and may be, for example, 50 ℃, 54 ℃, 57 ℃,60 ℃, 64 ℃, 67 ℃,70 ℃, 74 ℃, 77 ℃, 80 ℃, or the like.

Preferably, additional water is added to the super gravity mixture.

Preferably, the mass ratio of the supplementing water to the water in the raw material for producing the chlorinated polypropylene is 1:0.5-2, and can be, for example, 1:0.5, 1:0.6, 1:0.7, 1:0.9, 1:1.0, 1:1.2, 1:1.5, 1:1.8 or 1:2, etc. The invention further preferably adds water again, more advantageously to form a stable suspension.

The temperature of the chlorination reaction is preferably 60 to 130 ℃, and may be 60 ℃, 68 ℃, 76 ℃, 84 ℃, 92 ℃, 99 ℃, 107 ℃, 115 ℃, 123 ℃, 130 ℃, or the like.

Preferably, the temperature in the chlorination reaction is gradually increased.

Preferably, the initial temperature of the chlorination reaction is 60 to 90 ℃, and may be 60 ℃, 64 ℃, 67 ℃,70 ℃, 74 ℃, 77 ℃, 80 ℃, 84 ℃, 87 ℃, 90 ℃ or the like.

The final temperature of the chlorination reaction is preferably 100 to 130 ℃, and may be, for example, 100 ℃, 104 ℃, 107 ℃, 110 ℃, 114 ℃, 117 ℃, 120 ℃, 124 ℃, 127 ℃, 130 ℃, or the like.

The invention further prefers that the pressure and the temperature are gradually increased in the chlorination reaction process, which is favorable for improving the utilization rate of chlorine and obtaining the chlorinated polypropylene with higher quality.

Preferably, the pressure in the chlorination reaction is gradually increased.

Preferably, gas is introduced through at least two gas inlets in the chlorination reaction. The multi-point ventilation is realized through the multi-gas inlet, the problem that the diffusion speed of chlorine in the liquid phase is low is solved, and meanwhile, the contact area between the chlorine and the reaction suspension is increased, so that the chlorine can be more uniformly fed, the reaction effect is ensured, and the reaction efficiency is improved.

Preferably, the final pressure of the chlorination reaction is 0.15 to 0.4MPa, and may be, for example, 0.15MPa, 0.18MPa, 0.21MPa, 0.24MPa, 0.27MPa, 0.29MPa, 0.32MPa, 0.35MPa, 0.38MPa, 0.4MPa, or the like.

Preferably, the rotation speed of the chlorination reaction is 500-800 r/min, for example, 500r/min, 530r/min, 560r/min, 600r/min, 630r/min, 660r/min, 700r/min, 730r/min, 760r/min or 800r/min, etc.

Preferably, the method further comprises, after the chlorination reaction: flash evaporation acid removal is carried out on the system after the chlorination reaction, and the acid-removed chlorinated polypropylene is obtained.

The method particularly preferably adopts a flash evaporation acid removal mode after the reaction, so that the consumption of process water in the post-treatment can be greatly reduced, the rapid cooling of materials is realized, the recovery efficiency of waste acid is improved, and the cost and steps of the post-treatment are reduced; on the other hand, the method can realize the rapid deacidification of materials, reduce the influence of acid on chlorinated polypropylene products after reaction, and improve the chromaticity of the products.

Preferably, the pressure of the flash acid removal is-0.1 to 0.1MPa, for example, -0.1MPa, -0.05MPa, 0.01MPa, 0.02MPa, 0.03MPa or 0.05MPa, etc.

Preferably, the flash acid removal temperature is 120 to 150 ℃, and for example, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃, 150 ℃ or the like can be used.

Preferably, the process comprises, after flash removal of acid: and (3) washing, separating and drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Preferably, the separation comprises cyclonic separation.

Preferably, the drying comprises fluidized bed drying.

As a preferred technical solution of the first aspect of the present invention, the method includes the following steps:

(1) Mixing polypropylene, water, a surfactant, an initiator and a dispersing agent according to the mass ratio of 30-50:1000:0.5-1.2:0.6-1.2:0.8-2, and stirring at the temperature of 50-80 ℃ by vortex at the rotating speed of 300-600 r/min to obtain a primary suspension;

(2) The primary suspension is mixed by super gravity at 50-80 ℃ and 200-500 r/min to obtain micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension and chlorine gas introduced through at least two air inlets undergo chlorination reaction at 500-800 r/min, the initial temperature of the chlorination reaction is 60-90 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 100-130 ℃, and the final pressure is 0.15-0.4 MPa, so that chlorinated polypropylene is prepared;

(4) Flash evaporation acid removal is carried out on the system after the chlorination reaction under the pressure of-0.1 MPa and the temperature of 120-150 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

In a second aspect, the present invention provides a system installation for producing chlorinated polypropylene, said system installation being capable of operating the method for producing chlorinated polypropylene according to the first aspect; the system device comprises a vortex type stirring device with a heating device, a hypergravity mixing device and a chlorination device which are sequentially connected.

According to the system device disclosed by the invention, the vortex type stirring device, the hypergravity mixing device and the chlorination device are connected, so that continuous production of chlorinated polypropylene and uniform material conveying can be realized, and the product quality of the chlorinated polypropylene is improved.

Preferably, a vortex stirrer and a disc-shaped tube circulating heat exchanger are arranged in the vortex stirring device.

Preferably, a temperature monitoring component is further arranged in the vortex type stirring device.

Preferably, a feed inlet is arranged at the upper part of the vortex type stirring device.

Preferably, a discharge hole connected with the hypergravity mixing device is arranged at the lower part of the vortex type stirring device.

Preferably, the upper part of the super-gravity mixing device is provided with at least two feed inlets.

Preferably, one of the at least two feed ports is a makeup water feed port.

Preferably, a rotor is arranged inside the super-gravity mixing device.

Preferably, a discharge hole connected with the chlorination device is arranged at the lower part of the hypergravity mixing device.

Preferably, the chlorination device comprises a reaction kettle.

Preferably, an air inlet with an air inlet valve is arranged at the upper part of the chlorination device.

Preferably, a discharge port is arranged at the lower part of the chlorination device.

Preferably, the inner lower end of the chlorination device is further provided with at least two gas inlets.

Preferably, the chlorination device is internally provided with stirring means, preferably mechanical stirring.

Preferably, the chlorination device further comprises a circulating heat exchange line.

Preferably, the system apparatus further comprises a conveyor connected to the chlorination apparatus.

Preferably, the system device further comprises a flash deacidification device connected with the conveyor.

Preferably, the flash deacidification device comprises a flash tank, a nitrogen storage tank, an acid storage tank and a waste acid recovery tank.

Preferably, the system device further comprises a cleaning device, a separating device and a drying device which are sequentially connected with the flash evaporation deacidification device through a conveyor.

Preferably, a stirring member is provided in the cleaning device.

Preferably, a discharge hole is formed in the bottom of the cleaning device.

Preferably, the discharge port of the cleaning device is connected with the separating device.

Preferably, the separating apparatus comprises a cyclonic separator.

Preferably, the drying means comprises a fluid bed dryer.

Preferably, the bottom of the fluidized bed dryer is connected with a hot air blower.

Compared with the prior art, the invention has at least the following beneficial effects:

(1) The method for producing the chlorinated polypropylene has the advantages of high process flow automation degree, high chlorine utilization rate, chlorine utilization rate of over 96 percent and preferential condition of over 98 percent, realizes the recovery of waste acid which is a byproduct in production, greatly reduces the waste water quantity and the like, and ensures the stability and safety of the device;

(2) The system device for producing the chlorinated polypropylene ensures that the chlorinated polypropylene is not adhered and agglomerated after synthesis through optimization of the production device, and the chlorine content in the final chlorinated polypropylene can be kept above 34%, preferably above 58%, more preferably above 60%, and the product viscosity is above 1300 mPas, preferably above 1400 mPas; the general product is uniform in chlorination and white in appearance.

Drawings

FIG. 1 is a schematic view of a system for producing chlorinated polypropylene according to an embodiment of the invention.

In the figure: 1-a vortex type stirring device; 2-a supergravity mixing device; 3-chlorination device; 4-flash evaporation deacidification device; a 5-cyclone separator; 6-a cleaning device; 7-fluid bed dryer.

Detailed Description

The technical scheme of the invention is further described below by the specific embodiments with reference to the accompanying drawings.

The present invention will be described in further detail below. The following examples are merely illustrative of the present invention and are not intended to represent or limit the scope of the invention as defined in the claims.

It is to be understood that in the description of the present invention, the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus are not to be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", etc. may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

It should be noted that, in the description of the present invention, unless explicitly specified and limited otherwise, the terms "disposed," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art in a specific case.

It will be appreciated by those skilled in the art that the present invention necessarily includes the necessary piping, conventional valves and general pumping equipment for achieving the process integrity, but the foregoing is not a major inventive aspect of the present invention, and that the present invention is not particularly limited thereto as the layout may be added by themselves based on the process flow and the equipment configuration options.

As a specific embodiment of the present invention, there is provided a system apparatus for producing chlorinated polypropylene, which comprises a vortex stirring apparatus 1 with a heating apparatus, a supergravity mixing apparatus 2 and a chlorination apparatus 3, which are connected in this order, as shown in fig. 1.

A vortex stirrer and a disc-shaped tube circulating heat exchanger are arranged in the vortex stirring device 1; a temperature monitoring component is also arranged in the vortex type stirring device 1; the upper part of the vortex type stirring device 1 is provided with a feed inlet; the lower part of the vortex type stirring device 1 is provided with a discharge port connected with the hypergravity mixing device 2; the upper part of the super-gravity mixing device 2 is provided with a feed inlet; a rotor is arranged in the super-gravity mixing device 2; the lower part of the hypergravity mixing device 2 is provided with a discharge hole connected with the chlorination device 3.

The chlorination device 3 comprises a reaction kettle; an air inlet with an air inlet valve is arranged at the upper part of the chlorination device 3; a discharge hole is formed in the lower part of the chlorination device 3; at least two gas inlets are also arranged at the lower end of the inner part of the chlorination device 3; a stirring component, preferably mechanical stirring, is arranged in the chlorination device 3; the chlorination device 3 further comprises a circulating heat exchange pipeline.

The system device also comprises a conveyor connected with the chlorination device 3; the system device further comprises a flash evaporation deacidification device 4 connected with the conveyor; the flash evaporation deacidification device 4 comprises a flash evaporation tank, a nitrogen storage tank, an acid storage tank and a waste acid recovery tank; the system device further comprises a cleaning device 6, a separating device and a drying device which are sequentially connected with the flash evaporation deacidification device 4 through a conveyor; a stirring component is arranged in the cleaning device 6; a discharge hole is formed in the bottom of the cleaning device 6; the discharge port of the cleaning device 6 is connected with a separation device; the separating apparatus comprises a cyclone separator 5; the drying device comprises a fluidized bed dryer 7; the bottom of the fluidized bed dryer 7 is connected with a hot air blower.

As another embodiment of the present invention, there is provided a method for producing chlorinated polypropylene, the method comprising the steps of:

(1) The polypropylene, the water, the surfactant, the initiator and the dispersing agent are conveyed into a vortex type stirring device with a heating device according to the mass ratio of 30-50:1000:0.5-1.2:0.6-1.2:0.8-2, and the primary suspension is obtained after the vortex type stirring with the rotating speed of 300-600 r/min under the heating condition of 50-80 ℃;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device, supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 50-80 ℃ and 200-500 r/min to obtain micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge port of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas introduced through at least two air inlets at 500-800 r/min, wherein the initial temperature of the chlorination reaction is 60-90 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 100-130 ℃, and the final pressure is 0.15-0.4 MPa, so that chlorinated polypropylene is prepared;

(4) The system after the chlorination reaction is sent into a flash evaporation acid removal device for flash evaporation acid removal under the pressure of-0.1 to 0.1MPa and the temperature of 120 to 150 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Specific examples are described in detail below.

Example 1

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene (molecular weight of 80000-100000), 40kg of water, 40g of benzoyl peroxide, 60g of sodium polymethacrylate (number average molecular weight of 5400) and 40g of polyoxyethylene fatty alcohol ether (molecular weight of 358) with a particle size of 120-200 μm are conveyed into a vortex stirring device with a heating device, and a primary suspension is obtained after vortex stirring at a rotating speed of 300r/min under the heating condition of 65 ℃;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 40kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 65 ℃ and 200r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through 10 air inlets at the lower part at 800r/min, wherein the initial temperature of the chlorination reaction is 80 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 110 ℃, and the final pressure is 0.3MPa, so that chlorinated polypropylene is prepared;

(4) Sending the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of 0.05MPa and the temperature of 140 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 2

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene with the particle size ranging from 150 to 180 mu m (molecular weight of 80000 to 100000), 50kg of water, 40g of azodiisobutyronitrile, 60g of sodium dodecyl benzene sulfonate and 40g of polyoxyethylene fatty alcohol ether (molecular weight of 358) are conveyed into a vortex stirring device with a heating device, and a primary suspension is obtained after vortex stirring at the rotating speed of 350r/min under the heating condition of 80 ℃;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 25kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 80 ℃ and 300r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through air inlets at the lower part of the 5 parts at the speed of 700r/min, wherein the initial temperature of the chlorination reaction is 90 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 130 ℃, and the final pressure is 0.25MPa, so that chlorinated polypropylene is prepared;

(4) Sending the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of-0.1 MPa and the temperature of 150 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 3

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene (molecular weight of 80000-100000) with particle size range of 50-100 μm, 40kg of water, 30g of benzoyl peroxide, 80g of sodium polymethacrylate (number average molecular weight of 5400) and 20g of polyoxyethylene fatty alcohol ether (molecular weight of 358) are conveyed into a vortex stirring device with a heating device, and after vortex stirring at a rotating speed of 400r/min under the heating condition of 50 ℃, a primary suspension is obtained;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 50kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 50 ℃ and 350r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through 8 air inlets at the lower part at 500r/min, wherein the initial temperature of the chlorination reaction is 60 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 120 ℃, and the final pressure is 0.32MPa, so that chlorinated polypropylene is prepared;

(4) Sending the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of 0MPa and the temperature of 130 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 4

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene (molecular weight: 90000-100000) with particle size of 50-150 μm, 60kg of water, 40g of benzoyl peroxide, 50g of sodium polymethacrylate (number average molecular weight: 5400) and 40g of polyoxyethylene fatty alcohol ether (molecular weight: 358) are conveyed into a vortex stirring device with a heating device, and are subjected to vortex stirring at a rotating speed of 400r/min under the heating condition of 70 ℃ to obtain a primary suspension;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 40kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 75 ℃ at 400r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of a hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through 15 air inlets at the lower part at 600r/min, wherein the initial temperature of the chlorination reaction is 85 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 125 ℃, and the final pressure is 0.18MPa, so that chlorinated polypropylene is prepared;

(4) Feeding the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of-0.06 MPa and the temperature of 145 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 5

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene (molecular weight of 80000-100000), 40kg of water, 20g of benzoyl peroxide, 60g of sodium polymethacrylate (number average molecular weight of 5400) and 40g of polyoxyethylene fatty alcohol ether (molecular weight of 358) with a particle size of 100-200 μm are conveyed into a vortex stirring device with a heating device, and a primary suspension is obtained after vortex stirring at a rotating speed of 410r/min under the heating condition of 60 ℃;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 60kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 60 ℃ and 500r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through 10 air inlets at the lower part at 700r/min, wherein the initial temperature of the chlorination reaction is 60 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 110 ℃, and the final pressure is 0.25MPa, so that chlorinated polypropylene is prepared;

(4) Feeding the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of-0.03 Mpa and the temperature of 125 to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 6

This example provides a method of producing chlorinated polypropylene by the system apparatus for producing chlorinated polypropylene provided in the above embodiment, comprising the steps of:

(1) 2kg of polypropylene (molecular weight of 80000-100000) with particle size range of 50-200 μm, 40kg of water, 40g of benzoyl peroxide, 40g of sodium polymethacrylate (number average molecular weight of 5400) and 40g of polyoxyethylene fatty alcohol ether (molecular weight of 358) are conveyed into a vortex stirring device with a heating device, and after vortex stirring at a rotating speed of 450r/min under the heating condition of 75 ℃, a primary suspension is obtained;

(2) The primary suspension is conveyed to one feed inlet of a hypergravity mixing device through a vortex type stirring device to enter a central cavity, 70kg of supplementing water enters from the other feed inlet of the hypergravity mixing device, and is subjected to hypergravity mixing at 70 ℃ and 400r/min to obtain a micron-sized suspension of polypropylene particles;

(3) The micron-sized suspension is sent into a chlorination device through a discharge hole of the hypergravity mixing device, and is subjected to chlorination reaction with chlorine gas (ensuring multipoint dispersion and sample injection of the chlorine gas) introduced through air inlets at the lower part of 20 parts at 600r/min, wherein the initial temperature of the chlorination reaction is 90 ℃, the initial pressure is normal pressure, the temperature and the pressure in the chlorination reaction are gradually increased, the final temperature is 123 ℃, and the final pressure is 0.15MPa, so that chlorinated polypropylene is prepared;

(4) Sending the system after the chlorination reaction into a flash tank, and carrying out flash evaporation acid removal under the pressure of 0.1MPa and the temperature of 130 ℃ to obtain acid-removed chlorinated polypropylene; and (3) sequentially cleaning, cyclone separating and fluidized bed drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

Example 7

This example provides a process for producing chlorinated polypropylene which is the same as example 1 except that all water is added at once in step (1) and additional water is not added in step (2).

Example 8

This example provides a process for producing chlorinated polypropylene, which is the same as example 1 except that the fluidized bed is used for washing and deacidifying in step (3).

Comparative example 1

This comparative example provides a process for producing chlorinated polypropylene, which is the same as example 1 except that ordinary stirring and mixing are employed in step (1).

Comparative example 2

This comparative example provides a process for producing chlorinated polypropylene, which is the same as example 1 except that step (2) is not performed.

Comparative example 3

This comparative example provides a process for producing chlorinated polypropylene, which process step (2) uses ordinary stirring and mixing, and the remainder is the same as in example 1.

Comparative example 4

This comparative example provides a process for producing chlorinated polypropylene, the process comprising: 2kg of polypropylene, 40kg of water, 40g of benzoyl peroxide, 40g of sodium polymethacrylate and 40g of polyoxyethylene fatty alcohol are fed into an enamel kettle through a feed inlet at the upper part of the chlorination device, a chlorine gas inlet valve is arranged at the upper part of the kettle, chlorine gas is fed into the kettle through the gas inlet valve, a stirrer is arranged in the reaction kettle, a discharge outlet is arranged at the bottom of the chlorination reaction kettle, after the raw materials enter the chlorination reaction kettle, chlorine gas is fed in, the initial temperature of the chlorination reaction is 90 ℃ and normal pressure, the final temperature of the chlorination reaction is 123 ℃, the pressure is 0.15MPa, the stirring speed is 600r/min, after the reaction is finished, the materials are discharged through a discharge outlet, and the reacted materials are subjected to washing deacidification by adopting a fluidized bed, washing dehydration, cyclone separation and fluidized bed drying to obtain the chlorinated polypropylene.

The testing method comprises the following steps: the method comprises the steps of fully burning chlorinated polypropylene in oxygen, absorbing combustion products by a mixed solution of hydrogen peroxide and potassium hydroxide, converting chlorine atoms in a polymer into chloride ions, and titrating the mixed solution by using a mercury nitrate standard solution under the condition of pH 3-4 by using diphenyl azo carbohydrazide as an indicator to obtain chlorine content of the polyacid. Testing the chlorine content in the chlorinated polypropylene by the method; the viscosity in the chlorinated polypropylene was tested using the GBT1723-1993 method and the appearance of the chlorinated polypropylene was observed.

The test results of the above examples and comparative examples are shown in table 1.

TABLE 1

	Chlorine utilization (%)	Chlorine content (%)	Viscosity (mPa. S)	Appearance of
					Example 1	98.2	62.5	1428	Uniform white color
Example 2	97.2	58.4	1416	Uniform white color
					Example 3	97.6	34.8	894	Uniform white color
Example 4	98.0	63.1	1398	Uniform white color
					Example 5	97.4	47.5	957	Uniform white color
Example 6	97.8	57.9	1396	Uniform white color
					Example 7	97.5	58.7	1332	Uniform white color
Example 8	96.8	62.1	1419	Yellowish light yellow
					Comparative example 1	96.5	56.4	1027	Uniform white color
Comparative example 2	93.4	28.9	509	Yellowish light yellow
					Comparative example 3	92.8	31.4	683	Yellowish light yellow
Comparative example 4	96.2	48.2	980	Yellowish light yellow

From table 1, the following points can be seen:

(1) Comprehensive examples 1-8 show that white chlorinated polypropylene with different chlorine contents can be obtained by adopting different reaction conditions, the chlorine content can reach more than 34%, the preferred condition can reach more than 60%, the viscosity is more than 1300 mPas, and the preferred condition is more than 1400 mPas, and the application is wider; the utilization rate of chlorine in the method is as high as over 96 percent;

(2) Compared with example 1, example 7 directly adds all water in the feeding process, the chlorine content is slightly reduced, and compared with example 1, example 8 adopts fluidized bed to clean and deacidify, the appearance of the reactant has slight yellow because of short deacidification, thus showing that the invention obviously improves the chlorine content and the product chromaticity of the final product by optimizing the feeding and deacidification steps;

(3) It can be seen from the combination of examples 1 and comparative examples 1 to 4 that the mixing mode of the combination of vortex stirring and supergravity mixing adopted in example 1 has a chlorine utilization rate as high as 98.2%, a chlorine content of 62.5%, a viscosity of 1428mpa·s and a uniform white appearance, and the chlorine utilization rate and the chlorine content and viscosity of the products in comparative examples 1 to 4 are remarkably reduced, compared with the mixing mode of the combination not adopted in comparative examples 1 to 4, thereby showing that the quality of the final product is remarkably improved by adopting the combination of vortex stirring and supergravity mixing.

In conclusion, the method for producing the chlorinated polypropylene has the advantages of simple and safe process flow and high chlorine utilization rate, realizes the recovery of byproduct waste acid, greatly reduces the wastewater amount, and remarkably improves the product quality of the chlorinated polypropylene.

The applicant states that the detailed structural features of the present invention are described by the above embodiments, but the present invention is not limited to the above detailed structural features, i.e. it does not mean that the present invention must be implemented depending on the above detailed structural features. It should be apparent to those skilled in the art that any modifications of the present invention, equivalent substitutions of selected components of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope of the present invention and the scope of the disclosure.

Claims (39)

1. A process for producing chlorinated polypropylene, said process comprising:

the raw materials for producing the chlorinated polypropylene are stirred by vortex under the heating condition and then mixed by supergravity to obtain micron-sized suspension of polypropylene particles; the micron-sized suspension reacts with chlorine to prepare chlorinated polypropylene;

the raw materials for producing the chlorinated polypropylene comprise polypropylene, water, a surfactant, an initiator and a dispersing agent;

the mass ratio of the polypropylene to the water is 0.03-0.05:1;

the mass ratio of the surfactant to the water is 0.5-1.2:1000;

the mass ratio of the initiator to the water is 0.6-1.2:1000;

the mass ratio of the dispersing agent to the water is 0.8-2:1000;

the vortex stirring and heating are performed in a vortex stirring device with a heating device;

the rotational speed of the vortex stirring is 300-600 r/min;

the heating temperature is 50-80 ℃;

the rotating speed of the super-gravity mixing is 200-500 r/min;

the temperature of the super-gravity mixing is 50-80 ℃;

the temperature of the chlorination reaction is 60-130 ℃; the temperature in the chlorination reaction gradually rises; the initial temperature of the chlorination reaction is 60-90 ℃; the final temperature of the chlorination reaction is 100-130 ℃;

the pressure in the chlorination reaction gradually rises; the final pressure of the chlorination reaction is 0.15-0.4 MPa.

2. The method according to claim 1, wherein the polypropylene has a particle size of 200 μm or less.

3. The method of claim 1, wherein the surfactant comprises a polyoxyethylene fatty alcohol and/or a polyoxyethylene alkylphenol.

4. The method of claim 1, wherein the dispersant comprises sodium polymethacrylate and/or sodium dodecylbenzene sulfonate.

5. The method according to claim 1, wherein the initiator comprises benzoyl peroxide and/or azobisisobutyronitrile.

6. The method of claim 1 wherein additional water is added to the super gravity mixture.

7. The method according to claim 6, wherein the mass ratio of the supplementing water to the water in the raw material for producing the chlorinated polypropylene is 1:0.5-2.

8. The method of claim 1, wherein the chlorination reaction is conducted through at least two gas inlets.

9. The method according to any one of claims 1 to 5, further comprising, after the chlorination reaction: flash evaporation acid removal is carried out on the system after the chlorination reaction, and the acid-removed chlorinated polypropylene is obtained.

10. The method of claim 9, wherein the flash acid removal pressure is-0.1 to 0.1mpa.

11. The method of claim 9, wherein the flash acid removal temperature is 120-150 ℃.

12. The method of claim 9, wherein the method comprises, after flash acid removal: and (3) washing, separating and drying the chlorinated polypropylene after acid removal to obtain a chlorinated polypropylene product.

13. The method of claim 12, wherein the separating comprises cyclone separation.

14. The method of claim 12, wherein the drying comprises fluid bed drying.

15. The method according to claim 1, wherein the system means for operating the method for producing chlorinated polypropylene comprises a vortex stirring device with a heating device, a supergravity mixing device and a chlorination device connected in sequence.

16. The method of claim 15, wherein a vortex mixer and a disc tube circulation heat exchanger are disposed within the vortex mixer.

17. The method of claim 15, wherein a temperature monitoring component is further disposed within the vortex agitating device.

18. The method according to claim 15, wherein the upper part of the vortex agitating device is provided with a feed opening.

19. The method according to claim 15, wherein a lower part of the vortex mixer is provided with a discharge port connected to the hypergravity mixer.

20. The method according to claim 15, wherein the upper part of the super gravity mixing device is provided with at least two feed openings.

21. The method of claim 20, wherein one of the at least two feed ports is a makeup water feed port.

22. The method of claim 15, wherein a rotor is disposed within the hypergravity mixing device.

23. The method according to claim 15, wherein the lower part of the hypergravity mixing device is provided with a discharge port connected to the chlorination device.

24. The method of claim 15, wherein the chlorination device comprises a reaction kettle.

25. The method of claim 15, wherein the chlorination device is provided with an air inlet valve at an upper portion thereof.

26. The method according to claim 15, wherein the chlorination device is provided with a discharge opening in a lower portion thereof.

27. The method of claim 15, wherein the chlorination device is further provided at its inner lower end with at least two gas inlets.

28. The method of claim 15, wherein the chlorination device is internally provided with a stirring member.

29. The method of claim 15, wherein the chlorination device further comprises a recycle heat exchange line.

30. The method of claim 15, wherein the system assembly further comprises a conveyor coupled to the chlorination assembly.

31. The method of claim 30, wherein the system assembly further comprises a flash deacidification assembly coupled to the conveyor.

32. The method of claim 31, wherein the flash deacidification plant comprises a flash tank, a nitrogen storage tank, an acid storage tank, and a spent acid recovery tank.

33. The method of claim 32, wherein the system assembly further comprises a cleaning assembly, a separation assembly, and a drying assembly connected in series with the flash deacidification assembly via a conveyor.

34. The method of claim 33, wherein a stirring member is disposed within the cleaning device.

35. The method of claim 33, wherein the bottom of the cleaning device is provided with a discharge port.

36. The method of claim 35, wherein the outlet of the cleaning device is connected to a separation device.

37. The method of claim 33, wherein the separation device comprises a cyclone.

38. The method of claim 33, wherein the drying apparatus comprises a fluidized bed dryer.

39. The method of claim 38, wherein a hot air blower is connected to the bottom of the fluidized bed dryer.