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CN-119680579-B - Method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application of method

CN119680579BCN 119680579 BCN119680579 BCN 119680579BCN-119680579-B

Abstract

A method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application thereof. The invention belongs to the field of high-value conversion and application of waste biomass. The invention aims to solve the technical problems that the prior method can not synchronously realize the efficient recovery of lignin in the black liquor from the sulfate pulping process and the biochar conversion with excellent functionality. The method comprises the steps of placing waste biomass into a mixed solution of sodium hydroxide and sodium sulfide, heating at high temperature to obtain black liquor, adding ferric chloride hexahydrate into the black liquor, heating for reaction, centrifuging, drying, and then pyrolyzing in a tube furnace at high temperature. The invention takes the preparation of high-value products after lignin is separated and recovered as target guide, adopts corresponding means to precipitate lignin and endow the lignin with product conversion potential, fully utilizes sulfur elements existing in black liquor, introduces other metal elements, and further obtains the biochar with excellent functionality by optimizing process parameters. The obtained biochar is used for catalyzing the degradation of antibiotic wastewater by using the peroxymonosulfate.

Inventors

  • ZHUO SHENGNAN
  • WANG YUHAN
  • PANG YAO
  • GAO HONGLI
  • ZHANG GE

Assignees

  • 河南省科学院地理研究所

Dates

Publication Date
20260512
Application Date
20241213

Claims (9)

  1. 1. A method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor, which is characterized by comprising the following steps: S1, placing waste biomass into a mixed solution of sodium hydroxide and sodium sulfide, heating at high temperature, and carrying out solid-liquid separation to obtain black liquor; S2, adding ferric chloride hexahydrate into the black liquor, heating for reaction, centrifuging, freeze-drying the precipitate, and then pyrolyzing at high temperature in a tube furnace to obtain sulfur-doped nano zero-valent iron biochar; the molar ratio of sodium hydroxide to sodium sulfide in S1 is (4-6) 1, and the high-temperature heating temperature is 110-130 ℃; the concentration of ferric chloride hexahydrate in the black liquor in S2 is 0.4-0.5mol/L.
  2. 2. The method according to claim 1, wherein the waste biomass in S1 is straw, wood or livestock manure, the concentration of sodium hydroxide in the mixed solution is 0.5-1.5mol/L, and the ratio of the waste biomass to the mixed solution is 1g (15-25) mL.
  3. 3. The method according to claim 1, wherein the time of high temperature heating in S1 is 1.5 to 2.5 hours.
  4. 4. The process according to claim 1, wherein the heating in S2 is carried out at a temperature of 50-70 ℃ for a time of 0.5-1.5 hours, and the pyrolysis is carried out at a temperature of 650-750 ℃ for a time of 1-3 hours.
  5. 5. Use of the method according to any one of claims 1-4 for high value conversion of kraft pulping black liquor.
  6. 6. The sulfur-doped nano zero-valent iron biochar produced by the method of any one of claims 1-4.
  7. 7. The use of the sulfur-doped nano zero-valent iron biochar in the field of water treatment.
  8. 8. A method for the catalytic degradation of antibiotic wastewater using the biochar according to claim 6, wherein the method comprises: The sulfur doped nanometer zero-valent iron and the peroxymonosulfate are added into the antibiotic wastewater to be treated at room temperature.
  9. 9. The method according to claim 8, wherein the antibiotics comprise sulfamethoxazole and sulfamethazine, the concentration of the antibiotics in the wastewater is 5-15mg/L, and the addition amount of the biochar is 0.35-0.45g/L.

Description

Method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application of method Technical Field The invention belongs to the field of high-value conversion and application of waste biomass, and particularly relates to a method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application thereof. Background The waste biomass resources are large in quantity, and the wood fibers are high in content, so that the waste biomass resources are often used in the papermaking and pulping industry. Chemical processes such as the sulfate and caustic soda processes are one of the processes commonly used in papermaking pulping today. A large amount of pulping black liquor byproducts are generated in the chemical pulping process, and the black liquor is taken as biomass waste, has high yield and is difficult to degrade, and causes great difficulty for the treatment of factories. Not only increases the treatment cost, but also brings certain environmental pollution. Research shows that chemical pulping black liquor contains a large amount of lignin, and the lignin is known to be a biomass energy source and is a high molecular organic matter with excellent structural characteristics, so that the high-value product is high, and how to efficiently separate and recycle the lignin in the black liquor to realize harmless treatment and high-value conversion of the pulping black liquor becomes the key of the research. The current major focus on the separation and extraction of lignin from black liquor has focused on the extraction purity of lignin to produce biomass energy and high value added fuel products. However, under the condition of paying attention to separation and purification of lignin, the problem of low recovery yield of lignin is easily caused, and the complicated separation and extraction process increases the treatment cost. The acid precipitation method is one of the traditional mature methods for separating lignin, the process is simple, but the wastewater treatment technology after the process is implemented is also a difficult problem. Therefore, the lignin is co-precipitated by ferric chloride and sodium hydroxide, and then carbonized into nano zero-valent iron biochar in one step, so that the lignin is modified, trapped and converted with high value under the condition of not damaging the quality of the lignin. However, although the method realizes the efficient and convenient recovery of lignin in the black liquor, the obtained biochar still has insufficient functionality and needs to be improved. Disclosure of Invention The invention aims to solve the technical problem that the prior method can not synchronously realize the efficient recovery of lignin in pulping black liquor and the conversion of biochar with excellent functionality, and provides a method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application thereof. The technical scheme of the invention is as follows: The invention aims to provide a method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor, which comprises the following steps of: S1, placing waste biomass into a mixed solution of sodium hydroxide and sodium sulfide, heating at high temperature, and carrying out solid-liquid separation to obtain black liquor; S2, adding ferric chloride hexahydrate into the black liquor, heating for reaction, centrifuging, freeze-drying the precipitate, and then pyrolyzing at high temperature in a tube furnace to obtain the sulfur-doped nano zero-valent iron biochar. Further limited, the waste biomass in S1 is straw, wood or livestock manure. Further defined is that the concentration of sodium hydroxide in the mixed solution in S1 is 0.5-1.5mol/L. Further defined is that the molar ratio of sodium hydroxide to sodium sulfide in S1 is (4-6): 1. Further defined, the ratio of waste biomass to mixed solution in S1 is 1g (15-25) mL. Further defined, the high temperature heating in S1 is at a temperature of 110-130 ℃ for a time of 1.5-2.5 hours. Further defined, the concentration of ferric chloride hexahydrate in the black liquor in S2 is 0.40-0.5mol/L. Further defined, the temperature of heating in S2 is 50-70℃for a period of 0.5-1.5 hours. Further defined, the high temperature pyrolysis in S2 is at a temperature of 650-750 ℃ for a time of 1-3 hours. The second object of the invention is to provide an application of the method in high-value conversion of pulping black liquor. The invention also aims to provide the biochar prepared by the method. The invention aims at providing the application of the biochar prepared by the method in the field of water treatment. The fifth object of the present invention is to provide a method for advanced oxidation treatment of antibiotic wastewater, which comprises the steps of: the sulfur-doped nano zero-valent iron biochar catalytic oxidant is used