CN113372934A - Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium - Google Patents

Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium Download PDF

Info

Publication number
CN113372934A
CN113372934A CN202110774186.6A CN202110774186A CN113372934A CN 113372934 A CN113372934 A CN 113372934A CN 202110774186 A CN202110774186 A CN 202110774186A CN 113372934 A CN113372934 A CN 113372934A
Authority
CN
China
Prior art keywords
pyrolysis
biomass
fixed bed
bed reactor
potassium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110774186.6A
Other languages
Chinese (zh)
Inventor
胡沔
叶智恒
张海洋
潘志彦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University of Technology ZJUT
Original Assignee
Zhejiang University of Technology ZJUT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University of Technology ZJUT filed Critical Zhejiang University of Technology ZJUT
Priority to CN202110774186.6A priority Critical patent/CN113372934A/en
Publication of CN113372934A publication Critical patent/CN113372934A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B53/00—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form
    • C10B53/02—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form of cellulose-containing material
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B47/00—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion
    • C10B47/02—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with stationary charge
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C10B57/04—Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition
    • C10B57/06—Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition containing additives
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C10B57/08—Non-mechanical pretreatment of the charge, e.g. desulfurization
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

The invention discloses a method for preparing hydrogen by in-situ decarburization through potassium-calcium co-catalysis biomass pyrolysis, which comprises the following steps of adding KOH-Ca (OH)2Soaking biomass in the mixed solution, and performing dewatering and grinding treatment to obtain a pyrolysis precursor raw material; and then taking a proper amount of pyrolysis raw materials, and pyrolyzing the raw materials under the protection of Ar atmosphere to obtain a hydrogen-rich gas product. According to the invention, potassium and calcium elements respectively have catalytic and decarburization performances on biomass pyrolysis volatile matters, the potassium and calcium elements are loaded into a biomass structure by using impregnation pretreatment, and the biomass pyrolysis gas is promoted to be decarbonized and purified by the catalytic decarburization effect to prepare the hydrogen-rich gas. Potassium calciumThe content of hydrogen in biomass pyrolysis gas products can be remarkably improved by adding the elements, the volume percentage of the hydrogen in the pyrolysis gas is remarkably improved, and the effect of completely removing carbon dioxide is achieved. The raw materials are easy to obtain, the hydrogen proportion in the pyrolysis gas is high, and the gas component proportion can be manually regulated and controlled.

Description

Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium
Technical Field
The invention relates to a method for preparing hydrogen by in-situ decarburization of biomass under the co-catalysis of potassium and calcium.
Background
Fossil fuels are an important energy source to support current human activities, however, excessive consumption of fossil energy will result in CO in the atmospheric environment2The concentration continues to increase, causing a serious environmental problem. Active development of clean, efficient renewable energy sources is one of the most effective strategies to avoid the above problems. Among the numerous renewable energy sources, biomass is attracting attention based on its high-yield, carbon-neutral, clean, efficient characteristics. Catalytic pyrolysis is one of the most promising biomass energy utilization technologies.
Biomass catalytic pyrolysis generally has specific target products, such as H with high energy density2Or a chemical raw material synthesis gas. However, the gas product obtained in the present stage of biomass catalytic pyrolysis process has high tar content, H2Low ratio of carbon to oxygen, and certain CO2The heat value is low, and the grid connection use is difficult. And as a chemical feedstock, H is present2Low ratio of/CO, difficult regulation and control, and incapability of direct subsequent utilization. Patent CN 111377398A provides a method for preparing hydrogen by promoting biomass pyrolysis gasification by using catalyst (calcium-based carrier + Co, Fe), which mainly uses Ca to CO2And hydrogen is prepared under high temperature conditions by catalyzing tar with additionally added active substances (Co, Fe). However, the method has the problems of high temperature condition, complex catalyst preparation process, high cost of active components and the like.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under the condition of potassium-calcium co-catalysis, wherein KOH and Ca (OH)2The biomass is blended and impregnated, and is loaded in a biomass structure to serve as an in-situ catalytic agent and an absorbent, so that the high-efficiency catalytic cracking and decarbonization of the biomass are realized to prepare the hydrogen-rich fuel gas.
The method for preparing hydrogen by in-situ decarburization of biomass under the co-catalysis of potassium and calcium is characterized by comprising the following steps of:
1) reacting KOH with Ca (OH)2Dissolving in water to form mixed potassium-calcium solution; then, putting the biomass waste powder into a potassium-calcium mixed solution for impregnation treatment;
2) carrying out dehydration grinding treatment on the biomass sample subjected to the dipping treatment, and sieving to obtain a pyrolysis precursor raw material;
3) and (3) placing the pyrolysis precursor raw material obtained in the step 2) into a fixed bed reactor, and performing fast pyrolysis under the protection of Ar atmosphere, wherein pyrolysis gas generated by pyrolysis is a hydrogen-rich product subjected to in-situ decarburization.
The method for preparing hydrogen by in-situ decarburization of biomass under the co-catalysis of potassium and calcium is characterized in that in the step 1), the biomass waste powder is soybean straw powder, the water content is less than 10%, and the particle size is less than 0.15 mm.
The method for preparing hydrogen by in-situ decarburization through biomass pyrolysis under the co-catalysis of potassium and calcium is characterized in that in the step 1), Ca (OH)2The mass ratio of KOH to the biomass waste powder is 0.1-2.2: 1:2, preferably 2.0:1: 2.
The method for preparing hydrogen by in-situ decarburization of biomass under the co-catalysis of potassium and calcium is characterized in that in the step 1), the impregnation treatment process is as follows: and (3) placing the mixed liquid in a constant-temperature shaking table, oscillating for 10-15 h at room temperature, standing, and removing supernatant to obtain the product, namely the biomass sample after dipping treatment.
The method for preparing hydrogen by in-situ decarburization and pyrolysis of biomass under the co-catalysis of potassium and calcium is characterized in that in the step 2), the dehydration and grinding treatment process of a biomass sample after dipping treatment comprises the following steps: and (3) drying the sample in a blast drying box at the temperature of 100 ℃ and 120 ℃ for 10-15 h, and grinding and sieving by a 100-mesh sieve to obtain a product serving as a pyrolysis precursor raw material.
The method for preparing hydrogen by pyrolyzing and in-situ decarbonizing biomass under the co-catalysis of potassium and calcium is characterized in that in the step 3), the pyrolysis temperature is 580-620 ℃; the pyrolysis gas produced by pyrolysis contains H2、CO、CH4And CO2Four components, the total volume fraction of the four components in the pyrolysis gas is more than 85%; wherein H2Composition (I)At H2、CO、CH4And CO2The volume percentage of the four components is more than 40 percent.
The method for preparing hydrogen by in-situ decarburization through biomass pyrolysis under the co-catalysis of potassium and calcium is characterized in that Ca (OH) in the step 12The mass ratio of KOH to the biomass waste powder is 2.0:1:2, and when the pyrolysis temperature in the step 3) is 580-620 ℃, H in the pyrolysis gas2Component (B) is as follows2、CO、CH4And CO2The volume percentage of the four components is more than 70 percent, and CO2The volume content of the four gas products is less than 0.1 percent.
The method for preparing hydrogen by pyrolyzing and in-situ decarbonizing biomass under the co-catalysis of potassium and calcium is characterized in that the fixed bed reactor in the step 3) comprises a quartz tube fixed bed reactor and a vertical tubular furnace for heating a quartz tube, wherein the quartz tube fixed bed reactor is vertically arranged in the vertical tubular furnace, and the upper end of the quartz tube fixed bed reactor penetrates out of the vertical tubular furnace; a porcelain boat with an open upper end is suspended in the quartz tube fixed bed reactor, the porcelain boat is connected to a molybdenum wire, the upper end of the molybdenum wire penetrates out of the top of the quartz tube fixed bed reactor, and the upper and lower positions of the porcelain boat in the quartz tube fixed bed reactor can be adjusted by adjusting the molybdenum wire; the top of the quartz tube fixed bed reactor is connected with an air inlet pipeline for introducing Ar, and the bottom of the quartz tube fixed bed reactor is connected with a gas collecting device through a pipeline.
The method for preparing hydrogen by in-situ decarburization through biomass pyrolysis under the co-catalysis of potassium and calcium is characterized in that the fixed bed reactor is adopted to carry out pyrolysis reaction on a pyrolysis precursor raw material, and the operation steps are as follows:
s1: the pyrolysis precursor raw material is placed in a porcelain boat, and the porcelain boat is firstly adjusted to the inside of the upper end of a quartz tube fixed bed reactor, so that the porcelain boat is arranged above the vertical tube furnace; introducing Ar into the quartz tube fixed bed reactor, displacing and exhausting air in the quartz tube fixed bed reactor, and heating the quartz tube fixed bed reactor by a vertical tube furnace;
s2: and when the temperature of the quartz tube fixed bed reactor rises to a set temperature, downwards feeding the ceramic boat into the middle of the quartz tube fixed bed reactor, enabling the ceramic boat to be positioned in a high-temperature section of the quartz tube fixed bed reactor, carrying out pyrolysis under the protection of Ar atmosphere, and collecting gas discharged from the bottom of the quartz tube fixed bed reactor through a gas collecting device to obtain a pyrolysis gas product.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention utilizes potassium-calcium blending to dip the biomass raw material, promotes the catalytic decarbonization effect in the biomass pyrolysis process, and leads H in the pyrolysis gas-phase product2The ratio is more than 70%, and CO2And the biomass pyrolysis gas is basically and completely removed, so that the availability of the biomass pyrolysis gas is greatly increased.
2. The biomass raw material of the invention has low price and wide source, and H in pyrolysis gas2And the proportion of CO can be manually regulated and controlled, and the subsequent utilization is easy, for example, the CO can be used for Fischer-Tropsch synthesis to obtain a product with a high added value.
3. Compared with the reaction process of preparing hydrogen by pyrolyzing biomass by combining the existing double-chamber reactor and the oxygen carrier, the invention has lower requirements on the reaction device, and can be completed by using a common fixed bed reactor.
The alkali and alkaline earth metal content plays a crucial role in biomass pyrolysis. The alkali and alkaline earth metals can not only improve the pyrolysis reaction performance of the biomass, but also change the distribution of pyrolysis products and improve the quality of the products. The potassium has excellent catalytic performance and is a metal element which has the greatest influence on the distribution of pyrolysis products, and the addition of the potassium can promote the cracking of organic components in the biomass pyrolysis gas; calcium can react with carbon dioxide in the pyrolysis gas through carbonation to decarbonize the pyrolysis gas and promote H in the pyrolysis gas2Increase of the components. Therefore, the potassium/calcium element added into the biomass can promote the catalytic pyrolysis process of the biomass, adjust the balance of carbon dioxide in pyrolysis gas and increase H2The product components achieve the synergistic effect. The invention selects Ca (OH)2And KOH soaks the soybean straw powder together, and the hydrogen-rich gas is prepared by in-situ decarburization through the synergistic catalysis of the pyrolysis of the biomass.
Drawings
FIG. 1 is a schematic view of the pyrolysis apparatus of the present invention;
FIG. 2 shows no Ca (OH) added2Soybean straw material impregnated with KOH, and Ca (OH)2-thermogravimetric experiment result comparison graph of soybean straw raw material after KOH impregnation treatment;
FIG. 3 shows Ca (OH)2-XPS plot of soybean straw feedstock after KOH impregnation treatment;
FIG. 4 shows four target gases (H) in pyrolysis gases generated by pyrolysis of soybean straw and raw materials impregnated with Ca (OH)2 and KOH in different proportions at a pyrolysis temperature of 600 ℃ for 15 min2、CO、CH4、CO2) Yield, volume percentage of each component, and total gas production.
Detailed Description
The present invention is further illustrated by the following examples, which should not be construed as limiting the scope of the invention.
Example (b): compare FIG. 1
The schematic structure of the pyrolysis device is shown in fig. 1. The pyrolysis device comprises a quartz tube fixed bed reactor 2 and a vertical tube furnace 1 used for heating the quartz tube fixed bed reactor 2, wherein the quartz tube fixed bed reactor 2 is vertically arranged in the vertical tube furnace 1, and the upper end of the quartz tube fixed bed reactor 2 is penetrated out of the vertical tube furnace 1. A porcelain boat 3 with an open upper end is suspended in the quartz tube fixed bed reactor 2, the porcelain boat 3 is connected to a molybdenum wire 4, the upper end of the molybdenum wire 4 penetrates out of the top of the quartz tube fixed bed reactor 2, and the upper and lower positions of the porcelain boat 3 in the quartz tube fixed bed reactor 2 can be adjusted by adjusting the molybdenum wire 4; wherein, the top of the quartz tube fixed bed reactor 2 is connected with an air inlet pipeline for introducing Ar, and the bottom of the quartz tube fixed bed reactor is connected with a gas collecting device through a pipeline.
Wherein, the mode that the porcelain boat 3 is connected with the molybdenum wire 4 can be: the lower extreme of molybdenum filament 4 sets up a plurality of forked connecting wires, and passes through a plurality of forked connecting wires are connected fixedly with the upper end port lateral wall of porcelain boat 3, pull up porcelain boat 3 steadily through a plurality of connecting wires from this, and porcelain boat 3 is located quartz capsule fixed bed reactor 2's inside, and is equipped with the space between porcelain boat 3 and the quartz capsule fixed bed reactor 2. The upper end of the molybdenum wire 4 penetrates out of the top of the quartz tube fixed bed reactor 2.
In this application, gas collecting device includes three liquid bubble bottle 5, a filter 6 and an air pocket 7, and three liquid bubble bottle 5 connects gradually through the pipeline, and first liquid bubble bottle 5 is connected through pipeline and 2 bottoms of quartz capsule fixed bed reactor, and third liquid bubble bottle 5 is connected by the pipeline through filter 6 and air pocket 7, and three liquid bubble bottle 5 is inside all to contain the dichloromethane of certain volume. Gas discharged from the bottom of the quartz tube fixed bed reactor 2 firstly enters the liquid in the first liquid bubbling bottle 5 for bubbling, then sequentially enters the liquid in the second liquid bubbling bottle 5 and the third liquid bubbling bottle 5 for bubbling, and then is collected in the air bag 7 after passing through the filter 6.
The three liquid bubbling bottles 5 are provided in the present invention to facilitate the absorption of components such as tar that are not completely cracked in the gas generated after pyrolysis. In the example methods of the present invention 2-3, Ar was continuously fed into the quartz tube fixed bed reactor 2 to prevent the liquid in the three liquid bubbling bottles 5 from refluxing. Referring to fig. 1, the gas components collected in the gas bag 7 were analyzed by gas chromatography.
Example 1:
by using Ca (OH)2The process of carrying out dipping treatment on the soybean straw powder by KOH is as follows: reacting Ca (OH)2Adding KOH and the soybean straw powder into deionized water according to the mass ratio of 0:0:2, 0:1:2, 0.25:1:2, 0.5:1:2, 1:1:2 and 2:1:2 respectively, uniformly mixing, and oscillating at room temperature for 12 hours; standing for 1 h after oscillation is finished, and removing supernatant; drying the soaked wet biomass raw material at 105 ℃ for 12 h, grinding and sieving by a 100-mesh sieve to respectively prepare 6 batches of pyrolysis precursor raw materials with different potassium/calcium loading amounts.
Wherein, in the preparation process of the 6 batches of pyrolysis precursor raw materials with different potassium/calcium loading amounts, the mass ratio of the soybean straw powder to the deionized water is set to be 1: 20.
For exploring the loading condition of potassium and calcium elements in the soybean straw powder, Ca (OH)2KOH and the soybean straw powder are dipped in the mixture in a mass ratio of 2:1:2The pyrolysis precursor feedstock obtained after the treatment, and p-Ca (OH)2And KOH and the soybean straw powder are dipped in a mass ratio of 0:0: 2' to obtain a pyrolysis precursor raw material (namely the soybean straw raw material), and the pyrolysis precursor raw material and the soybean straw powder are subjected to X-ray photoelectron spectroscopy analysis respectively, wherein the test result is shown in figure 2. It can be found that the blending impregnation can load a large amount of potassium/calcium elements on a biomass structure and greatly increase the oxygen element content of the biomass raw material.
To explore the effect of potassium/calcium on the pyrolytic characteristics of biomass, on "Ca (OH)2Performing thermogravimetric experiment on the pyrolysis precursor raw material obtained after the impregnation treatment of KOH and the soybean straw powder in the mass ratio of 2:1:2 ", wherein the detailed process comprises the following steps: heating the raw materials under Ar protective atmosphere, taking 30 ℃ as an initial temperature, and heating to 800 ℃ at a heating rate of 10 ℃/min. The thermogravimetric experiment result of the sample at the temperature of 30-800 ℃ is shown in figure 3. TG (%) is the proportion of mass loss of the sample with increasing temperature. The curve obtained by the first derivative of the temperature with respect to the DTG (%/min), i.e., the TG curve, is expressed as the weight loss rate of the sample with a gradual rise in the heating temperature by the microperimetric thermogravimetric analysis.
From fig. 3 it can be observed that: the sample has four main weight loss stages at the temperature of 30-800 ℃, the first stage is a dehydration stage of the sample within the temperature range of 30-180 ℃, the mass loss of the stage is 8%, the mass of the sample remains 92%, and the maximum weight loss rate is reached at the temperature of 92 ℃; the second stage is carried out within the range of 200-350 ℃, mainly is a stage of removing and cracking simple organic matter volatile components in the sample, the mass loss of the stage is 9%, the mass residue of the sample is 83%, and the maximum weight loss rate is reached at 255 ℃; the third stage mainly occurs under the condition of 350-600 ℃, the mass loss of the stage is 13%, the mass of the sample remains 70%, and the temperature of the maximum weight loss peak is 443 ℃, and the stage is mainly caused by the decomposition of more complex organic components in the sample; the fourth stage occurs in the temperature range higher than 600 ℃, and the fourth stage is mainly formed by the organic components in the biomass, such as the carbon action, the intensified condensation degree and the CO absorbed by potassium/calcium2As a result of decomposition of the formed carbonate.
Example 2:
the reaction was carried out by using a pyrolysis apparatus as shown in FIG. 1, in this example, without adding Ca (OH)2Soaking soybean stalk powder with KOH, and adding Ca (OH)2KOH are soaked in different proportions, and the fast pyrolysis experiment is carried out on the soybean straw powder, which explores Ca (OH)2And the influence of the KOH dipping concentration on the yield of pyrolysis gas and gas components of the soybean straws is as follows:
s1: 2 g of pyrolysis precursor raw material is placed in a porcelain boat;
s2: the porcelain boat is firstly adjusted to the inside of the upper end of the quartz tube fixed bed reactor, and in comparison with fig. 1, the porcelain boat is positioned above the vertical tube furnace. Continuously introducing Ar with the flow rate of 50 mL/min into the quartz tube fixed bed reactor, displacing and exhausting air in the quartz tube fixed bed reactor, and heating the quartz tube fixed bed reactor through a vertical tube furnace;
s3: when the temperature of the quartz tube fixed bed reactor rises to a target pyrolysis temperature, the ceramic boat is conveyed downwards into the middle of the quartz tube fixed bed reactor, the ceramic boat is positioned in a high-temperature section of the quartz tube fixed bed reactor, pyrolysis reaction is started under the protection of Ar atmosphere, a sample in the ceramic boat instantly rises to the target temperature from room temperature, organic matters in the sample are rapidly separated out, and a large amount of micromolecular gas is generated. The pyrolysis time was 15 min, the gas product was collected by an air bag (the air bag started collecting the gas product after the start of the pyrolysis reaction), and the gas composition was detected by gas chromatography.
In the above step S1, the pyrolysis precursor raw material used in example 1 was Ca (OH)2-KOH-soybean straw powder after impregnation treatment in a ratio of 0:0:2, 0:1:2, 0.25:1:2, 0.5:1:2, 1:1:2, and 2:1: 2;
in the step S3, the target pyrolysis temperature is set to be 600 ℃, the total yield of four gases in the pyrolysis gas of different soybean straw samples at high temperature, and H2Yield, CO2Yield and H2the/CO ratio is summarized in Table 1.
TABLE 1
Figure DEST_PATH_IMAGE001
Wherein in Table 1, the yields of the four target gases refer to the yield of H in the pyrolysis gas2、CO、CH4And CO2Total volume of four components; h2The ratio of H in the pyrolysis gas2The ratio of the four gas components; CO 22The ratio of the carbon dioxide to the carbon dioxide is CO in the pyrolysis gas2The ratio of the four gas components; h2The term/CO means H2Ratio of production to CO production.
As can be seen from table 1: gas H produced by biomass pyrolysis with potassium catalysis only2There is a significant increase, however, in the corresponding CO2The concentration is increased, the potassium-calcium concerted catalysis improves the phenomenon, and the H in the pyrolysis gas of the soybean straws is increased along with the increase of the calcium impregnation concentration2Significant increase in yield, CO2The yield gradually decreases, mainly due to the CO produced by the organic matter during the cracking process, with increasing calcium concentration2Gradually tends to be completely absorbed, so that the components of the cracked gas of the soybean straws tend to generate H2. And the proportion of CO in the cracking gas is gradually reduced, so that H is generated2the/CO gradually increased from 1.36 to 5.68, thus indicating a controlled addition of Ca (OH)2Can lead the pyrolysis gas to strip the component H2the/CO is regulated and controlled between 1.36 and 5.68, and the quality requirement of the Fischer-Tropsch synthesis gas is met.
Under the condition of different potassium-calcium impregnation concentrations, the pyrolysis gas of the soybean straws at high temperature is analyzed by gas chromatography, and four target gases (namely H) in the pyrolysis gas are determined2、CO、CH4And CO2) The yields of the individual components were further analyzed and the results are summarized in FIG. 4.
As can be seen in fig. 4: the potassium-calcium impregnation treatment has a great promotion effect on the yield of the soybean straw pyrolysis gas product, and the components of the gas product are obviously changed. Conversion of the main gaseous product from CO to H2And as the calcium concentration increases, H in the four target gases2The volume ratio is gradually increased. This is probably due to the potassium calcium CO-catalysing the cracking of volatiles and the in situ CO2CO caused by adsorption removal2Absorption of (2) promotes waterSteam shift takes place so that H2Becomes the leading product of the pyrolysis gas, and when the potassium-calcium impregnation ratio reaches 2:1:2, the pyrolysis gas of the soybean straws achieves the purpose of completely removing CO2By the phenomenon of (1), pyrolysis gas H2The concentration is further increased.
The statements in this specification merely set forth a list of implementations of the inventive concept and the scope of the present invention should not be construed as limited to the particular forms set forth in the examples.

Claims (9)

1. A method for preparing hydrogen by in-situ decarburization of biomass under the co-catalysis of potassium and calcium is characterized by comprising the following steps:
1) reacting KOH with Ca (OH)2Dissolving in water to form mixed potassium-calcium solution; then, putting the biomass waste powder into a potassium-calcium mixed solution for impregnation treatment;
2) carrying out dehydration grinding treatment on the biomass sample subjected to the dipping treatment, and sieving to obtain a pyrolysis precursor raw material;
3) and (3) placing the pyrolysis precursor raw material obtained in the step 2) into a fixed bed reactor, and performing fast pyrolysis under the protection of Ar atmosphere, wherein pyrolysis gas generated by pyrolysis is a hydrogen-rich product subjected to in-situ decarburization.
2. The method for preparing hydrogen by in-situ decarburization by pyrolysis of biomass under co-catalysis of potassium and calcium as claimed in claim 1, wherein in the step 1), the biomass waste powder is soybean straw powder, the water content is less than 10%, and the particle size is less than 0.15 mm.
3. The method for preparing hydrogen by in-situ decarburization conducted by pyrolyzing biomass through co-catalysis of potassium and calcium and according to claim 1, wherein in the step 1), Ca (OH)2The mass ratio of KOH to the biomass waste powder is 0.1-2.2: 1:2, preferably 2.0:1: 2.
4. The method for preparing hydrogen by in-situ decarburization by pyrolysis of biomass under co-catalysis of potassium and calcium as claimed in claim 1, wherein in the step 1), the impregnation treatment process comprises: and (3) placing the mixed liquid in a constant-temperature shaking table, oscillating for 10-15 h at room temperature, standing, and removing supernatant to obtain the product, namely the biomass sample after dipping treatment.
5. The method for preparing hydrogen by in-situ decarburization and pyrolysis of biomass under co-catalysis of potassium and calcium as claimed in claim 1, wherein in the step 2), the dehydration and grinding treatment process of the biomass sample after the dipping treatment comprises the following steps: and (3) drying the sample in a blast drying box at the temperature of 100 ℃ and 120 ℃ for 10-15 h, and grinding and sieving by a 100-mesh sieve to obtain a product serving as a pyrolysis precursor raw material.
6. The method for preparing hydrogen by pyrolyzing and in-situ decarbonizing biomass through potassium-calcium co-catalysis according to claim 1, wherein the fixed bed reactor in the step 3) comprises a quartz tube fixed bed reactor and a vertical tubular furnace for heating a quartz tube, the quartz tube fixed bed reactor is vertically arranged in the vertical tubular furnace, and the upper end of the quartz tube fixed bed reactor penetrates out of the vertical tubular furnace; a porcelain boat with an open upper end is suspended in the quartz tube fixed bed reactor, the porcelain boat is connected to a molybdenum wire, the upper end of the molybdenum wire penetrates out of the top of the quartz tube fixed bed reactor, and the upper and lower positions of the porcelain boat in the quartz tube fixed bed reactor can be adjusted by adjusting the molybdenum wire; the top of the quartz tube fixed bed reactor is connected with an air inlet pipeline for introducing Ar, and the bottom of the quartz tube fixed bed reactor is connected with a gas collecting device through a pipeline.
7. The method for preparing hydrogen by in-situ decarburization by pyrolysis of biomass under co-catalysis of potassium and calcium as claimed in claim 6, wherein the pyrolysis reaction of the pyrolysis precursor raw material is carried out by using the fixed bed reactor according to the following steps:
s1: the pyrolysis precursor raw material is placed in a porcelain boat, and the porcelain boat is firstly adjusted to the inside of the upper end of a quartz tube fixed bed reactor, so that the porcelain boat is arranged above the vertical tube furnace; introducing Ar into the quartz tube fixed bed reactor, displacing and exhausting air in the quartz tube fixed bed reactor, and heating the quartz tube fixed bed reactor by a vertical tube furnace;
s2: and when the temperature of the quartz tube fixed bed reactor rises to a set temperature, downwards feeding the ceramic boat into the middle of the quartz tube fixed bed reactor, enabling the ceramic boat to be positioned in a high-temperature section of the quartz tube fixed bed reactor, carrying out pyrolysis under the protection of Ar atmosphere, and collecting gas discharged from the bottom of the quartz tube fixed bed reactor through a gas collecting device to obtain a pyrolysis gas product.
8. The method for preparing hydrogen by in-situ decarburization by pyrolysis of biomass through co-catalysis of potassium and calcium as claimed in claim 1, wherein in the step 3), the pyrolysis temperature is 580-620 ℃; the pyrolysis gas produced by pyrolysis contains H2、CO、CH4And CO2Four components, the total volume fraction of the four components in the pyrolysis gas is more than 85%; wherein H2Component (B) is as follows2、CO、CH4And CO2The volume percentage of the four components is more than 40 percent.
9. The method for preparing hydrogen by in-situ decarburization conducted by pyrolyzing biomass through co-catalysis of potassium and calcium and according to claim 7, wherein Ca (OH) in the step 1)2The mass ratio of KOH to the biomass waste powder is 2.0:1:2, and when the pyrolysis temperature in the step 3) is 580-620 ℃, H in the pyrolysis gas2The components are H2, CO and CH4And CO2The volume percentage of the four components is more than 70 percent, and CO2The volume content of the four gas products is less than 0.1 percent.
CN202110774186.6A 2021-07-08 2021-07-08 Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium Pending CN113372934A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110774186.6A CN113372934A (en) 2021-07-08 2021-07-08 Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110774186.6A CN113372934A (en) 2021-07-08 2021-07-08 Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium

Publications (1)

Publication Number Publication Date
CN113372934A true CN113372934A (en) 2021-09-10

Family

ID=77581519

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110774186.6A Pending CN113372934A (en) 2021-07-08 2021-07-08 Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium

Country Status (1)

Country Link
CN (1) CN113372934A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115212916A (en) * 2022-09-21 2022-10-21 中国农业科学院农业环境与可持续发展研究所 Method for producing hydrogen by in-situ catalytic pyrolysis of agricultural wastes such as straws

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103084158A (en) * 2011-11-07 2013-05-08 北京低碳清洁能源研究所 Adsorption catalysis heat carrier for biomass pyrolysis

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103084158A (en) * 2011-11-07 2013-05-08 北京低碳清洁能源研究所 Adsorption catalysis heat carrier for biomass pyrolysis

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
白斌等: "氢氧化钾催化木屑热解特性影响研究", 《可再生能源》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115212916A (en) * 2022-09-21 2022-10-21 中国农业科学院农业环境与可持续发展研究所 Method for producing hydrogen by in-situ catalytic pyrolysis of agricultural wastes such as straws

Similar Documents

Publication Publication Date Title
Durán et al. Microalgae: Potential precursors of CO2 adsorbents
CN110813359B (en) Ruthenium-based ammonia synthesis catalyst with nitrogen-doped porous carbon material as carrier and preparation method thereof
Daorattanachai et al. Type of contribution: Research article catalytic activity of sewage sludge char supported Re-Ni bimetallic catalyst toward cracking/reforming of biomass tar
US8236271B2 (en) Process for producing hydrogen gas and carbon nanotubes from catalytic decomposition of ethanol
CN108927194A (en) N doping ruthenium base biology Pd/carbon catalyst and its preparation method and application
CN111363572B (en) Method for co-producing gas-liquid fuel, chemicals and carbon materials by catalytic pyrolysis of biomass
CN110721690B (en) Ni-Fe bimetal multifunctional catalyst for biological oil steam reforming hydrogen production
CN113145103B (en) Hydrodesulfurization catalyst and preparation method and application thereof
CN113372934A (en) Method for preparing hydrogen by performing pyrolysis and in-situ decarburization on biomass under co-catalysis of potassium and calcium
CN102227491A (en) Manufacture of vinyl chloride monomer from renewable materials, vinyl chloride monomer thus-obtained, and use
CN111229237B (en) Preparation method and application of novel metal-biochar-based hydrogenation catalyst
CN101352686B (en) Catalyst used for hydrogen production by catalyzing and hydrogen production method by catalyzing
CN112961693A (en) Method for preparing hydrogen-rich fuel gas by utilizing quick co-pyrolysis of dehydrated Fenton sludge and biomass
CN106807382A (en) A kind of preparation method of high dispersive Ni/C catalyst
CN113089015B (en) Nitrogen-doped carbon quantum dot and preparation method thereof, and reduced graphene oxide and preparation method and application thereof
CN112973747B (en) Preparation method of transition metal carbide catalyst and application of transition metal carbide catalyst in preparation of high value-added synthesis gas from biomass solid waste
CN101348234A (en) Method for preparing hydrogen from biomass
CN109529847A (en) A kind of method and application preparing carbon base catalyst using waste residue of Chinese herbs
CN112090397A (en) Method for improving heat value of blast furnace tail gas by using biochar and obtaining carbon with high specific surface area
SHI et al. Preparation and characterization of Ni/TPC catalyst and applied in straw pyrolysis gas reforming
CN106590705A (en) Method for secondarily reforming tar by utilizing in-situ composite semicoke made from high alkaline coal and biomass
CN110898821A (en) Ternary metal-containing porous carbon Cu-ZnCo @ C adsorption desulfurizer and preparation method thereof
CN115974076A (en) Preparation method and application of hydrothermal nitrogen-doped cork-based activated carbon
JP2007023084A (en) Catalyst for biomass gasification
CN102516322A (en) Method for preparing levoglucosenone with magnetic solid phosphoric acid catalyst

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20210910