RU2747560C1 - Method for producing liquid plant-based biological fuel - Google Patents

Abstract

FIELD: fuel industry.

SUBSTANCE: invention relates to methods of producing liquid biological fuel from plant-based waste or products. The invention can be used to produce diesel engine and light heating oil, wherein plant-based waste or products, particularly wood waste such as shavings, sawdust, wood chips, tree bark or agricultural vegetable waste such as straw, vegetable tops and others, can be used as a source of raw material. Old trees and shrubs formed during felling and cleaning of areas can be used as raw material. The substance of the method consists in a 45 to 50% water solution of a 1-12 series heteropoly acid in an oxidized form with the chemical formula H₅[PW₁₀V₂O₄₀] being poured into a galvanic bath, then electrodes being lowered into the galvanic bath which can be made of stainless steel and are then connected to a direct current voltage source, and with a potential difference of 5 to 7 V between the cathode and the anode under direct electric current on the cathode the anionic complex [PW₁₀V₂O₄₀]^5- to [PW₁₀V₂O₄₀]^17- being reduced, then a portion of the resulting water solution with a reduced heteropoly acid with the chemical formula H₁₇[PW₁₀V₂O₄₀] being collected using an outlet tube and pumped into a reactor which in turn can be made of polyethylene or fluoroplastic, and after feeding a portion of the water solution of the heteropoly acid containing heteropoly acid in reduced form ground plant-based waste is loaded into the reactor, wherein sawdust, shavings, tree bark, leaves, deadwood, moss can be used as plant-based waste, the reactor then being heated to a temperature of 97 to 105°С and the plant waste being directly processed into hydrocarbon fractions in this temperature range, heteropolyacids of a reduced form being periodically added to the reactor, controlling the process of changing of the color of the solution, wherein violet indicates predominance of heteropolyanion of a reduced form, and light yellow indicates predominance of heteropolyanions of an oxidized form, then a portion of the heteropolyacid in the reduced form being added to the reactor if during the process the solution begins to brighten, assessment of the process also being controlled by release of carbon dioxide after the solution in the reactor stops brightening, the release of carbon dioxide stops and the solid waste residues completely dissolve, disabling heating of the reactor and cooling it to a temperature of 50 to 60°С, then loading the mixture consisting of a water solution of the heteropolyacid in the reduced form and liquid hydrocarbons into an apparatus for decanting the mixture, wherein separation into a hydrocarbon phase and a water phase which is a water solution of the heteropolyacid in the reduced form takes place during decanting, then the liquid hydrocarbon phase being sent to the fuel collector for further fractional distillation, and the water solution of the heteropolyacid in the reduced form being sent to the bubbler, wherein the heteropolyacid is oxidized to the initial oxidized state under the impact of atmospheric oxygen, then the oxidized solution of the heteropolyacid being directed again to the galvanic bath.

EFFECT: provided is production of liquid biological fuel from plant-based waste or products.

1 cl, 1 dwg, 1 ex

Description

The invention relates to methods for producing liquid biofuel from waste or plant products.

The invention can be used to obtain diesel engine and light heating oil, where the source of raw materials can be waste or plant products, in particular wood waste, such as shavings, sawdust, wood chips, tree bark or plant waste from agricultural products, for example, straw, tops and others. Old trees and shrubs can be used as raw materials, which must be disposed of during felling and cleaning of areas.

Known work on obtaining liquid hydrocarbon fuel from sawdust using a beam of accelerated electrons [1].

Lignin and cellulose, the main components of wood, were used as raw materials for obtaining liquid hydrocarbon fuel. In fact, the simple process of obtaining liquid fuel takes place in two stages. First, dry distillation of wood is carried out without access to air. Well-dried sawdust is heated with a beam of accelerated electrons to 400-450 ° C in a flow of methane or a propane-butane mixture. Under the influence of the energy of ionizing radiation, lignin and cellulose decompose. Then the vaporous products of radiolysis are cooled and condensed in a water cooler at 15 ° C.

With this method of obtaining the products of dry distillation, depending on the type of wood, contain from several percent to a quarter of aromatic components formed during the decomposition of lignin and the main products of radiolysis of cellulose - furans, aldehydes, alkyl ketones and carboxylic acids.

The authors argue that this method using radiolysis makes it possible to obtain up to 15 kg / kWh of organic liquid from pine, spruce, birch or aspen. The yield of a useful product reaches 55-65% of the mass of the irradiated wood.

The authors also argue that this method does not form water. However, wood waste usually contains a large amount of water, which will inhibit radiolysis. Therefore, before the process, it is necessary to carry out drying with a large expenditure of energy.

The authors also did not indicate what efficiency is achieved when processing other varieties of trees and other waste.

The main disadvantage of this method is the need to use a methane or propane-butane atmosphere, in which the products of dry distillation are converted into cyclic and acyclic alkanes, tetrahydrofuran derivatives, aliphatic alcohols and ethers, as a result of which there is a fairly large consumption of useful combustible gases.

A known method of producing methane and its derivatives [2].

The essence of the method lies in the fact that 10-80% aqueous solution of heteropoly acid number 2-18, having the chemical formula H ₆ [P ₂ W ₁₈ O _62], is heated to a temperature of 70-140 C °, then immersed in a solution of lead or a copper plate and wait 3-15 minutes before the start of the reduction of the anionic complex [P ₂ W ₁₈ O ₆₂ ] ^6- , then through the solution at a pressure of 700-800 mm Hg. a gas mixture with a carbon dioxide concentration of not more than 60 vol.% and an oxygen concentration of not less than 5 vol.% is passed through until one of the saturated hydrocarbons is obtained.

This method relates to methods for producing methane and its derivatives, where carbon dioxide is used as the main raw material. This method uses a 2-18 series heteropoly acid having the formula H ₆ [P ₂ W ₁₈ O ₆₂ ], and a similar interaction mechanism with the patented invention. However, this invention is about gaseous hydrocarbons.

Closest to the patentable invention is a method for producing liquid organic fuels from carbon dioxide, carbon monoxide and water [3].

The invention discloses a method for producing liquid organic fuels from carbon dioxide, carbon monoxide and water, including the use of a heteropoly acid of the 2-18 series having the chemical formula H ₆ [P ₂ W ₁₈ O] ₆₂ , where the oxidation state of tungsten is +6, which is irradiated in the presence of iron and zinc plates at a temperature of minus 5 - plus 50 ° C by electromagnetic radiation in the wavelength range from 3⋅10 ⁵ to 10 ^-2 nm and shorter in order to change the oxidation state of tungsten from +6 to +3 and +2, after which water a solution of both heteropoly acids goes directly to the synthesis of organic liquid fuel, where, in the presence of chromium and nickel chips at temperatures from +10 to + 70 ° C, liquid organic fuel is formed with simultaneous oxidation of anionic complexes of heteropoly acids to an oxidized state, during which an aqueous solution of heteropoly acid is formed , having the chemical formula H ₆ [P ₂ W ₁₈ O ₆₂ ], after which the resulting mixture enters the container for decks antation, where the separation of liquid fuel and an aqueous solution of heteropolyacid takes place, which can again be used for synthesis. The technical result consists in obtaining liquid organic fuels from carbon dioxide, carbon monoxide and water at lower temperatures using various external energy sources in the form of electromagnetic radiation.

In this method, carbon dioxide and carbon monoxide are used as the main raw materials. Also in this method, as in the method for producing methane and its derivatives, the same active component is used - a heteropoly acid of the 2-18 series, having the chemical formula H ₆ [P ₂ W ₁₈ O ₆₂ ], and a similar interaction mechanism with the patent invention.

The technical problem of the present invention is to simplify a method for producing liquid biofuel from waste or plant products.

The essence of the patented method lies in the chemical interaction of an aqueous solution of a heteropoly acid (HPA) of the Keggin type 1-12 series, having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ] [4, 5], with waste or products of plant origin, namely, the interaction with cellulose, lignin and hemicellulose. Heteropoly acids or heteropoly compounds possess catalytically active properties [6, 7, 8], as well as the ability to redox reactions, during which multielectron and "multiproton" exchanges can reversibly occur. Due to these properties, CHPs can attach to themselves a large number of hydrogen atoms and then give them away.

The technological process of the patentable invention can be divided into several stages.

The first stage consists in the reduction of CHP, having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ], by direct electric current to the restored state. This process takes place at the cathode, which can be expressed by the following chemical reaction equation:

H ₅ [PW ₁₀ V ₂ O ₄₀ ] + 6H ₂ O = H ₁₇ [PW ₁₀ V ₂ O ₄₀ ] + 3O ₂ ,

where the oxidation state of tungsten changes from +6 to +5, and vanadium from +5 to +4.

The second technological stage consists in the interaction of the selected HPA of the reduced form with waste and products of plant origin, namely: with lignin, cellulose and hemicellulose. In the course of this process, the so-called process of hydrogenation of the wood composition occurs, as a result of which the oxidation state of tungsten and vanadium goes back to a stable maximum oxidation state for tungsten +6, and for vanadium +5. During this process, CHP molecules lose some of their hydrogen atoms with the release of carbon dioxide, and the wood pulp turns into a liquid hydrocarbon mixture. This process is carried out with heating.

The third technological stage consists in decanting the resulting mixture, during which the formed liquid hydrocarbons and an aqueous solution of CHP are separated.

Due to the good solubility of HPA in water and the lack of solubility in hydrocarbons, HPA is practically not consumed during the process. The residues of the reduced form of CHP are passed through a bubbler, where CHP is again oxidized with atmospheric oxygen to the initial state, after which it is again fed into the galvanic bath to the cathode for reduction.

The reverse process can be expressed by the following reaction equation:

H ₁₇ [PW ₁₀ V ₂ O ₄₀ ] + 3O ₂ = H ₅ [PW ₁₀ V ₂ O ₄₀ ] + 6H ₂ O

The obtained liquid hydrocarbons are subjected to fractional distillation to obtain target products such as gasoline, kerosene and diesel fuel.

The technical result of the patentable invention is to create a single technological chain of the processes, during which liquid hydrocarbon fractions are formed.

The process of obtaining liquid hydrocarbons according to the described method is carried out as follows. As the main reagent used heteropolyacid series 1-12, having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ]. The presented figure shows a schematic flow diagram of the patented method. A 45-50% aqueous solution of heteropoly acid in oxidized form having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ] is preliminarily poured into the galvanic bath 1. Next, electrodes, which can be made of stainless steel, are lowered into the bath, after which they are connected to a DC voltage source 2. Further, with a potential difference of 5-7 V between cathode 3 and anode 4, under the action of a DC electric current at cathode 3, the anionic complex with [PW ₁₀ V ₂ O ₄₀ ] ^5- to [PW ₁₀ V ₂ O ₄₀ ] ^17- . Next, a portion of the formed aqueous solution of heteropolyacid in a reduced form, having the chemical formula H ₁₇ [PW ₁₀ V ₂ O ₄₀ ], is withdrawn with the help of the outlet tube 5, and with the help of the pump 6 it is pumped into the reactor 7, which in turn can be made of polyethylene or fluoroplastic. After a portion of the specified aqueous solution of heteropolyacid is fed into the reactor through line 8, shredded plant waste is loaded, which can be sawdust, wood shavings, bark, leaves, dead wood, moss. Next, the reactor is heated to a temperature of 97-105 ° C, and in this temperature range, the process of processing plant waste into hydrocarbon fractions is carried out directly, periodically adding a solution of heteropolyacid in a reduced form to the reactor and controlling the processing process by changing the color of the solution. The purple color of the solution indicates the predominance of the heteropolyanion of the reduced form [PW ₁₀ V ₂ O ₄₀ ] ^17- , and the light yellow color indicates the predominance of the heteropolyanion of the oxidized form [PW ₁₀ V ₂ O ₄₀ ] ^5- . If during the process the solution begins to brighten, a portion of the heteropoly acid in reduced form is added to the reactor. Also, during the process, carbon dioxide is released. The processing process is stopped after the solution in the reactor ceases to lighten and the release of carbon dioxide stops, which indicates the presence of an excess of the reduced form of heteropoly acid and the termination of the reaction of the interaction of plant waste with the heteropoly acid. A visual assessment is also made. The solid part of the waste must be completely dissolved. Next, the heating of the reactor is turned off and the resulting mixture is cooled to a temperature of 50-60 ° C, after which the mixture consisting of an aqueous solution of the reduced form of the heteropoly acid and liquid hydrocarbons is transferred through line 9 to a device for decanting the mixture 10, in which separation into a hydrocarbon phase occurs and an aqueous phase, which is an aqueous solution of a heteropoly acid in reduced form. The liquid phase after filtration is separated into a hydrocarbon phase and an aqueous phase, which is an aqueous solution of a heteropoly acid in a reduced form. The liquid hydrocarbon phase formed during decantation is poured through line 11 into fuel collector 12 and sent for further fractional distillation to obtain gasolines, kerosene and diesel fuel (not shown in the figure).

An aqueous solution of a heteropoly acid in a reduced form after decantation by gravity is directed through line 13 to a bubbler 14, where, under the action of air oxygen, which is supplied to a bubbler through line 15, a part of the solution containing a heteropoly acid in a reduced form is oxidized under the action of atmospheric oxygen to the initial state of a heteropoly acid oxidized form, after which, using the pump 16, the specified solution is directed through line 17 into the galvanic bath 1.

Example

It was taken:

- 2100 g of vegetable waste, consisting of alder shavings and pine sawdust with a water content of not more than 10%;

- 47% aqueous solution of CHP in oxidized form with the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ].

In the galvanic bath 1 was filled with a 47% aqueous solution of HPA in oxidized form, having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ]. Then the electrodes, which were made of stainless steel AISI 321, were lowered into the galvanic bath. After that they were connected to a DC voltage source 2. With a potential difference of 5.5 V between cathode 3 and anode 4 under the action of a DC electric current at cathode 3 performed the reduction of the HPA anionic complex from [PW ₁₀ V ₂ O ₄₀ ] ^5- to [PW ₁₀ V ₂ O ₄₀ ] ^17- . Next, a portion of the formed HPA aqueous solution in the reduced form of the formula H ₁₇ [PW ₁₀ V ₂ O ₄₀ ] was withdrawn with the help of the outlet tube 5, and with the help of the pump 6 it was pumped into the reactor 7 made of fluoroplastic. After feeding a portion of the specified aqueous solution into the reactor, the prepared crushed waste of plant origin was loaded into it (in the diagram, the loading is carried out along line 8). After that, the reactor was heated to a temperature of 100 ° C, and at this temperature, the process of processing the taken waste into hydrocarbon fractions was carried out by periodically adding a HPA solution in a reduced form to the reactor. The processing process was monitored by changing the color of the solution. The purple color of the solution indicated the predominance of the heteropolyanion of the reduced form [PW ₁₀ V ₂ O ₄₀ ] ^17- , and when the solution began to brighten, this meant the oxidation of the heteropoly anion to the initial state [PW ₁₀ V ₂ O ₄₀ ] ^5- and the solution became light-colored. yellow. If during the process the solution began to brighten, then a portion of the reduced form of CHP was again added to the reactor. Also, the process was accompanied by the release of carbon dioxide. After the solution in the reactor ceased to brighten and the release of carbon dioxide stopped, and the solid waste of plant origin was transferred to the liquid phase, that is, their dissolution, the heating of the reactor was turned off and the resulting mixture was cooled to a temperature of 50-60 ° C, after which the resulting The mixture, consisting of an aqueous solution of HPA in reduced form and liquid hydrocarbons, was transferred (in the figure along line 9) to a decanter 10, where it was separated into a liquid hydrocarbon phase and an aqueous phase, which is an aqueous solution of HPA in a reduced form. The liquid hydrocarbon phase formed during decantation (in the figure along line 11) was poured into the fuel collector 12, after which fractional distillation was performed to obtain gasoline, kerosene and diesel fractions. The aqueous solution of HPA of the reduced form after decantation, which remained at the lower level of the device 10, was directed by gravity (along line 13 in the figure) to the bubbler 19, where, under the action of air oxygen, that part of the solution that contained HPA in the reduced form was oxidized to the initial state, then there is up to the oxidized HPA with the chemical formula H ₁₇ [PW ₁₀ V ₂ O ₄₀ ]. Then, using the pump 20, the solution containing the specified form of CHP was sent back to the galvanic bath 1.

Output. As a result of the described method, 900 g of a hydrocarbon fraction was obtained, which was subjected to fractional distillation, as a result of which the following products were obtained:

- gasoline fraction - 210 g;

- kerosene fraction - 227 g;

- light diesel fraction - 315 g;

The remainder contains dark diesel fraction and tar.

Information sources

1. "Radiolysis of wood: some aspects of obtaining liquid fuel", Ponomarev AV, Tsivadze A.Yu. Institute of Physical Chemistry and Electronics named after A.N. Frumkin of the Russian Academy of Sciences, Moscow, volume 424, number 1, year 2009, pp. 57-60, Journal "REPORTS OF THE ACADEMY OF SCIENCES" // Publishing house // ISSN: 0869-5652.

2. Patent RU 2218320.

3. Patent RU 2582125.

4. Keggin J.F. Structure of molecule of 12-phosphotungstic acid // Nature. - 1993. - V-p. 908-909.

5. Kozhevnikov I.V., Matveev K.I. Heteropolyacids in catalysis // Advances in Chemistry. - 1982.vol. 51. - No. 11 - p. 1875-1896.

6. Catalytic oxidation of СО by heteropolyacids (ΗΡΑ) and dioxygen in the presence of Pd (II) salt-HPA-H2O system.https: //doi.org/10.1016/0304-5102 (86) 87078-X

7. Polyoxometalates: Synthesis and Structure - From Building Blocks to Emergent Materials. https://doi.org/10.1016/B978-0-08-097774-4.00210-2

8. Catalysis for Fine Chemical Synthesis - Catalysis by Polyoxometalates 2 https://doi.org/10.1055/s-2003-37336.

Claims (1)

A method of obtaining liquid biofuel of plant origin, including the use of a heteropoly acid as the main reagent, characterized in that a 45-50% aqueous solution of a 1-12 row heteropoly acid is poured into the galvanic bath in an oxidized form having the chemical formula H ₅ [PW ₁₀ V ₂ O ₄₀ ], after which electrodes, which can be made of stainless steel, are lowered into the galvanic bath, after which they are connected to a DC voltage source, and at a potential difference of 5-7 V between the cathode and anode under the action of a DC electric current at the cathode occurs reduction of the anionic complex [PW ₁₀ V ₂ O ₄₀ ] ^5- to [PW ₁₀ V ₂ O ₄₀ ] ^17- , then a portion of the resulting aqueous solution with a heteropoly acid in a reduced form having the chemical formula H ₁₇ [PW ₁₀ V ₂ O ₄₀ ], and with the help of a pump it is pumped into the reactor, which in turn can be made of polyethylene or fluoroplastic, and after feeding a portion of an aqueous solution of a heteropoly acid containing a reduced heteropoly acid, shredded plant waste is loaded into the reactor, which can be sawdust, wood shavings, tree bark, leaves, deadwood, moss, after which the reactor is heated to a temperature of 97-105 ° With and in this temperature range, the process of processing plant waste into hydrocarbon fractions is carried out directly, periodically adding a heteropolyacid in a reduced form to the reactor, while controlling the process by changing the color of the solution, where the purple color indicates the predominance of the heteropolyanion in the reduced form, and light yellow the color indicates the predominance of heteropolyanions in the oxidized form, and if during the process the solution began to brighten, then a portion of the heteropoly acid in the reduced form is added to the reactor; gas, after the solution in the reactor ceases to brighten and the release of carbon dioxide stops and the solid residues of waste completely dissolve, the heating of the reactor is turned off and cooled to a temperature of 50-60 ° C, after which a mixture consisting of an aqueous solution of a heteropoly acid in a reduced form and liquid hydrocarbons are transferred to a device for decanting the mixture, during which separation into a hydrocarbon phase and an aqueous phase, which is an aqueous solution of a heteropoly acid in a reduced form, is carried out, then the liquid hydrocarbon phase is sent to a fuel collector for further fractional distillation, and an aqueous solution of a heteropoly acid in a reduced form is directed to a bubbler, where, under the influence of atmospheric oxygen, the heteropoly acid is oxidized to the initial oxidized state, after which the oxidized solution of the heteropoly acid is again sent to the galvanic bath.

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