CN111792870B - Method for preparing anti-freezing and early-strength water reducing agent from acetic acid wastewater - Google Patents
Method for preparing anti-freezing and early-strength water reducing agent from acetic acid wastewater Download PDFInfo
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- CN111792870B CN111792870B CN202010527613.6A CN202010527613A CN111792870B CN 111792870 B CN111792870 B CN 111792870B CN 202010527613 A CN202010527613 A CN 202010527613A CN 111792870 B CN111792870 B CN 111792870B
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/10—Accelerators; Activators
- C04B2103/12—Set accelerators
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/30—Water reducers, plasticisers, air-entrainers, flow improvers
- C04B2103/302—Water reducers
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/60—Agents for protection against chemical, physical or biological attack
- C04B2103/601—Agents for increasing frost resistance
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00017—Aspects relating to the protection of the environment
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Abstract
The invention provides a method for preparing an antifreezing early strength water reducing agent by acetic acid wastewater, which comprises the steps of weighing a certain amount of acetic acid wastewater, adding the acetic acid wastewater into a reaction kettle, adding water or not adding water, adding a certain amount of alkali into the acetic acid wastewater while stirring, and adjusting the pH value of the acetic acid wastewater to 7-10; then adding a sulfonating agent into the mixture, stirring and mixing the mixture evenly, slowly dripping acetone into the mixture, and then sulfonating and preserving heat; slowly dripping formaldehyde solution after the heat preservation is finished, condensing and preserving heat for 1.5-3h after the dripping is finished, and supplementing or not supplementing water after the heat preservation is finished. According to the invention, acetic acid in acetic acid wastewater is utilized to perform a neutralization reaction with alkali to obtain sodium acetate, then the sodium acetate plays a role in early strength in concrete, the treated wastewater is directly used for synthesizing the water reducing agent, the early strength effect of the water reducing agent can be increased, and no harm and pollution to human bodies and environment can be caused, and no waste of resources and energy can be caused.
Description
Technical Field
The invention relates to the technical field of water reducing agents, and particularly relates to a method for preparing an anti-freezing early-strength water reducing agent from acetic acid wastewater.
Background
The water reducing agent is used as the most additive for concrete, can reduce the water consumption in concrete mixtures, and has a good effect on improving the concrete performance of concrete. At present, a first-generation common water reducer, a second-generation high-efficiency water reducer and a third-generation high-performance water reducer are researched. The aliphatic water reducing agent (sulfonated acetone-formaldehyde condensate), the sulfamic acid high-efficiency water reducing agent (sulfamic acid-formaldehyde condensate) and the naphthalene water reducing agent (naphthalene sulfonate-formaldehyde condensate) are used as second-generation water reducing agents, and compared with third-generation polycarboxylate water reducing agents, the water reducing and collapse protecting performances of the aliphatic water reducing agent, the aliphatic water reducing agent and the sulfamic acid-based high-efficiency water reducing agent are much poorer due to the defects of the structures of the aliphatic water reducing agent, the sulfamic acid-based high-efficiency water reducing agent and the naphthalene sulfonate-formaldehyde condensate, but the naphthalene water reducing agent, the aliphatic water reducing agent and the sulfamic acid-based high-efficiency water reducing agent have wide raw material sources, low cost, better adaptability and wider application.
Acetic acid is a chemical product, and is very important in chemical industrial production. It has a boiling point of 117.9 deg.C at normal pressure and a relative density of 1.0492, and is readily soluble in water, alcohols, ethers and carbon tetrachloride. Acetic acid has strong corrosivity and stabbing pain to skin, and belongs to a secondary organic acidic corrosive product. Acetic acid is used as an important reaction raw material, a solvent and the like, is widely applied to various industries, can derive hundreds of downstream products, is a key raw material or solvent of chemical products such as ethylene, acetic anhydride, cellulose acetate, acetate esters, terephthalic acid, acetate and the like, and has very wide application value. However, in the chemical industrial production process using acetic acid, anhydrous acetic acid, or the like, a certain amount of acetic acid-containing wastewater is produced. If the waste water is directly discharged, the waste water has important influence on the environment and also causes great waste of acetic acid resources. Therefore, the recovery and the reuse of the low-concentration acetic acid wastewater have huge economic benefits and long-term environmental impact. In recent years, in order to deal with global climate change, global economic crisis and other situations, China also puts higher requirements on energy conservation and emission reduction of chemical industry than before. At present, the recycling method of the acetic acid-containing wastewater mainly comprises a rectification method, an extraction method, an adsorption method, a membrane separation method, an esterification method and the like. Among the developed physical and chemical processes, various methods have their own characteristics, and the distillation method has large energy consumption and high cost; other components are required to be added for azeotropic distillation, extractive distillation, extraction method and the like, and are recycled after separation; the main treatments of adsorption separation, membrane separation and the like are acetic acid aqueous solution with lower concentration, and are still in experimental research stage. Therefore, no mature and complete process exists so far, which can solve the problem of recycling the acetic acid aqueous solution with the whole concentration ideally. However, with the increasing enhancement of environmental protection consciousness of people, the method for sustainable development, circular economy, resource recovery and environmental protection is the main direction for acetic acid wastewater utilization in the future, and the research of various methods should be continuously enhanced in the future to find a process method suitable for the characteristics of the method and meet the requirements of actual production.
Disclosure of Invention
The invention provides a method for preparing an antifreezing early-strength water reducing agent from acetic acid wastewater. The treated wastewater is directly used for synthesizing the water reducing agent, so that the early strength effect of the water reducing agent can be improved, and the waste of resources and energy can not be caused due to the damage and pollution to human bodies and the environment.
In order to achieve the aim, the invention provides a method for preparing an anti-freezing early-strength water reducing agent from acetic acid wastewater, which comprises the following steps:
a method for preparing an antifreezing and early strength water reducing agent from acetic acid wastewater comprises the following steps:
weighing a certain amount of acetic acid wastewater, adding into a reaction kettle, adding water or not, adding a certain amount of alkali while stirring, and adjusting the pH value to 7-10; then adding a sulfonating agent into the mixture, stirring and mixing the mixture evenly, slowly dripping acetone into the mixture, and then sulfonating and preserving heat; slowly dripping formaldehyde solution after the heat preservation is finished, condensing and preserving heat for 1.5-3h after the dripping is finished, and supplementing or not supplementing water after the heat preservation is finished.
Preferably, the alkali is solid sodium hydroxide, sodium hydroxide aqueous solution or sodium hydroxide waste liquid obtained in industrial production.
Preferably, the sulfonating agent is sodium sulfite, sodium bisulfite, sodium metabisulfite, SO3At least one of (1).
Preferably, the sulfonating agent is sodium sulfite, sodium bisulfite, sodium metabisulfite, SO3At least one of the above-mentioned materials is compounded with at least one of sulfanilic acid, sodium styrene sulfonate and sodium lignosulfonate.
Preferably, the temperature in the processes of adding acetone dropwise and sulfonating and preserving heat is not higher than 56 ℃, and the time of sulfonating and preserving heat is 0.5-1.5 h.
Preferably, the formaldehyde is dripped for 1-3h, and the temperature is 90-96 ℃ during the dripping process.
Preferably, the condensation incubation temperature is 90-96 ℃.
Preferably, the mass ratio of the sulfonating agent to acetone is 1: 1-1.5:1, wherein the mass ratio of the formaldehyde to the acetone is 2.5:1-2.75:1
Preferably, the formaldehyde is industrial formaldehyde.
Preferably, the mass percentage concentration of the formaldehyde is 35-37%.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the invention, acetic acid in the acetic acid wastewater is utilized to perform a neutralization reaction with alkali to obtain sodium acetate, and then the sodium acetate has an early strength effect in concrete. The method has simple treatment of the acetic acid wastewater, and realizes the resource utilization of the acetic acid wastewater with different concentrations.
2. The wastewater treated by the method is directly used for synthesizing the water reducing agent, so that the early strength effect of the water reducing agent is improved, and the waste of resources and energy is avoided without damaging and polluting human bodies and environment. The water reducing agent has the advantages of simple synthesis, easily controlled reaction conditions, simple production process and no discharge of three wastes.
3. Compared with the existing sulfonated acetone-formaldehyde condensate and sulfamic acid formaldehyde condensate, the product of the invention has better anti-freezing effect and early strength effect.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 160 parts of acetic acid wastewater, adding the acetic acid wastewater into a reaction kettle, adding 233 parts of water, adding 27 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 133 parts of sodium sulfite (90 wt%), slowly dropwise adding 98 parts of acetone after uniformly stirring and mixing, then sulfonating and preserving heat for 30min, dropwise adding the acetone and keeping the temperature of the sulfonation and preserving heat to be not higher than 56 ℃; and slowly dropwise adding 270 parts of formaldehyde solution (35-37 wt%) after heat preservation is finished, wherein the dropwise adding time is 1.5h, and the temperature is 90-96 ℃ in the dropwise adding process. After the dropwise addition, condensation and heat preservation are carried out at 90-96 ℃ for 2 hours, and 30 parts of water is supplemented after the heat preservation is finished.
Example 2:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 360 parts of acetic acid wastewater, adding into a reaction kettle, adding 60 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 133 parts of sodium sulfite (90 wt%), stirring and mixing uniformly, slowly dropwise adding 98 parts of acetone, carrying out sulfonation heat preservation reaction for 30min, dropwise adding the acetone, and keeping the temperature not higher than 56 ℃ in the sulfonation heat preservation process; and slowly dropwise adding 270 parts of formaldehyde solution (35-37 wt%) after heat preservation is finished, wherein the dropwise adding time is 1.5h, and the temperature is 90-96 ℃ in the dropwise adding process. After the dropwise addition, condensation and heat preservation are carried out at 90-96 ℃ for 2 hours, and 30 parts of water is supplemented after the heat preservation is finished.
Example 3:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 300 parts of acetic acid wastewater, adding the acetic acid wastewater into a reaction kettle, adding 70 parts of water, adding 50 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 133 parts of sodium sulfite (90 wt%), stirring and mixing uniformly, slowly dropwise adding 98 parts of acetone into the mixture, performing sulfonation heat preservation reaction for 60min, dropwise adding the acetone, and keeping the temperature of the sulfonation heat preservation process to be not higher than 56 ℃; and slowly dropwise adding 270 parts of formaldehyde solution (35-37 wt%) after heat preservation is finished, wherein the dropwise adding time is 1.5h, and the temperature is 90-96 ℃ in the dropwise adding process. After the dropwise addition, condensation and heat preservation are carried out at 90-96 ℃ for 2 hours, and 30 parts of water is supplemented after the heat preservation is finished.
Example 4:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 420 parts of acetic acid wastewater, adding 70 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 143 parts of sodium sulfite (90 wt%), stirring and mixing uniformly, slowly dropwise adding 100 parts of acetone, performing sulfonation heat preservation reaction for 90min, dropwise adding acetone, and keeping the temperature not higher than 56 ℃ in the sulfonation heat preservation process; and slowly dropwise adding 270 parts of formaldehyde solution (35-37 wt%) after heat preservation is finished, wherein the dropwise adding time is 1.5h, and the temperature is 90-96 ℃ in the dropwise adding process. After the dripping is finished, condensing and preserving heat for 2 hours at the temperature of 90-96 ℃, and cooling.
Example 5:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 420 parts of acetic acid wastewater, adding 70 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 143 parts of sodium sulfite (90 wt%), stirring and mixing uniformly, slowly dropwise adding 100 parts of acetone, performing sulfonation heat preservation reaction for 30min, dropwise adding acetone, and keeping the temperature not higher than 56 ℃ in the sulfonation heat preservation process; and slowly dropwise adding 270 parts of formaldehyde solution (35-37 wt%) after heat preservation is finished, wherein the dropwise adding time is 1.5h, and the temperature is 90-96 ℃ in the dropwise adding process. After the dripping is finished, condensing and preserving heat for 2 hours at the temperature of 90-96 ℃, and cooling.
Example 6:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 420 parts of acetic acid wastewater, adding 70 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 7-8, then adding 146 parts of sodium sulfite (90 wt%) and 25 parts of sodium lignosulfonate, stirring and mixing uniformly, slowly dropwise adding 100 parts of acetone, performing sulfonation heat preservation reaction for 30min, dropwise adding the acetone, and keeping the temperature of the sulfonation heat preservation process to be not higher than 56 ℃; after the heat preservation is finished, 276 parts of formaldehyde solution (35-37 wt%) is slowly dropped into the mixture, the dropping time is 1.5h, and the temperature is 90-96 ℃ in the dropping process. After the dripping is finished, condensing and preserving heat for 2 hours at the temperature of 90-96 ℃, and cooling.
Example 7:
a method for preparing an antifreezing early strength water reducing agent from acetic acid wastewater comprises the following steps of:
weighing 480 parts of acetic acid wastewater, adding 100 parts of sodium hydroxide aqueous solution (32 wt%) while stirring, adjusting the pH value to 11-13, then adding 126 parts of sodium sulfite (90 wt%), stirring and mixing uniformly, slowly dropwise adding 102 parts of acetone, performing sulfonation heat preservation reaction for 30min, dropwise adding acetone, and keeping the temperature not higher than 56 ℃ in the sulfonation heat preservation process; after the heat preservation is finished, 276 parts of formaldehyde solution (35-37 wt%) is slowly dripped into the mixture, the dripping time is 1.5h, and the temperature is 90-96 ℃ in the dripping process. After the dropwise addition, the mixture is condensed and insulated for 1h at the temperature of 90-96 ℃, and the material begins to become thick to generate a gel phenomenon.
According to the relevant regulations of the water reducing agent in GB 8076 plus 2008 "concrete admixture", the net slurry and the out-of-machine slump of the concrete doped with the water reducing agent prepared in the embodiment of the invention, a common aliphatic water reducing agent (represented by FAS-1) of Anhui Xin solid environmental protection technology limited company and a sulfamic acid-based high-efficiency water reducing agent (represented by SNF-1) and the ratio of the compressive strength of the concrete for 1 day, 3 days, 7 days and 28 days to the compressive strength of the reference concrete are measured, wherein the slump is 10min, 20min, 30min, 40min, 50min and 60 min. The test adopts standard cement, and the mixing amount of the water reducing agent is 0.8 percent (fold-fixed) of the weight of the cement. The test results are shown in table 1.
Table 1:
as shown in Table 1, by adjusting the material proportion and the process steps, the sulfonated acetone-formaldehyde condensate and the sulfamic acid formaldehyde condensate with better water reducing and collapse protecting effects can be obtained, and when the water reducing effect is close to that, the 1-day compressive strength ratio of the sulfonated acetone-formaldehyde condensate and the sulfamic acid formaldehyde condensate is obviously higher than that of FSA-1 and SNF-1, so that the frost resistance of the concrete is greatly improved.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (7)
1. A method for preparing an antifreezing and early strength water reducing agent from acetic acid wastewater is characterized by comprising the following steps:
weighing a certain amount of acetic acid wastewater, adding into a reaction kettle, adding water or not, adding a certain amount of alkali while stirring, and adjusting the pH value to 7-10; then adding a sulfonating agent, stirring and mixing uniformly, slowly dripping acetone into the mixture, sulfonating and preserving heat, dripping acetone, and preserving heat at the temperature of not higher than 56 ℃ in the sulfonating and preserving heat process for 0.5-1.5 h; slowly dripping a formaldehyde solution into the mixture after the heat preservation is finished, wherein the dripping time of the formaldehyde is 1-3h, and the temperature is 90-96 ℃ in the dripping process; after the dropwise addition, carrying out condensation heat preservation for 1.5-3h, wherein the condensation heat preservation temperature is 90-96 ℃, and supplementing or not supplementing water after the heat preservation is finished.
2. The method for preparing the antifreeze early strength water reducing agent according to the acetic acid wastewater of claim 1, wherein the alkali is solid sodium hydroxide, sodium hydroxide aqueous solution or sodium hydroxide waste liquor obtained in industrial production.
3. The method for preparing the antifreeze and early strength water reducing agent according to the claim 1, wherein the sulfonating agent is sodium sulfite, sodium bisulfite, sodium pyrosulfite, SO3At least one of (1).
4. The method for preparing the antifreeze and early strength water reducing agent according to the claim 1, wherein the sulfonating agent is sodium sulfite, sodium bisulfite, sodium pyrosulfite, SO3At least one of the above-mentioned materials is compounded with at least one of sulfanilic acid, sodium styrene sulfonate and sodium lignosulfonate.
5. The method for preparing the antifreeze and early strength water reducing agent according to the acetic acid wastewater of claim 1, wherein the mass ratio of the sulfonating agent to acetone is 1: 1-1.5:1, and the mass ratio of the formaldehyde to the acetone is 2.5:1-2.75: 1.
6. The method for preparing the antifreeze early strength water reducing agent according to the acetic acid wastewater of claim 1, wherein the formaldehyde is industrial formaldehyde.
7. The method for preparing the antifreeze and early strength water reducing agent according to the acetic acid wastewater of claim 6, wherein the mass percentage concentration of the formaldehyde is 35-37%.
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| CN106277914A (en) * | 2016-08-08 | 2017-01-04 | 合肥永佳新材料科技有限公司 | A kind of anti-freezing concrete water reducer and preparation method thereof |
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