Preparation And Application Of Kerosene Co-refining Residue-based Activated Carbon

Coal-oil co-processing technology is to use the low-grade heavy oil as a solvent to directly liquefy the coal,which characterizes in producing liquid fuels with a low cost and high energy efficiency.However,a large amount of solid waste（asphaltene sands,AS）mainly composed of asphaltene and metal oxides is produced during the coal-oil co-processing process.As indicated from the main components of AS,it is a hazardous solid waste with potentially serious environmental issues if it is not properly treated.However,up to now,the inverstigation on the resource utilization of coal-oil co-processing resdue is rare.To realize the high additional value utilization of residue not only promote the more extensive application of coal-oil co-processing technology but also decrease the environmental pollution.Therefore,it is of great significance to explore the efficient utilization of residue.The coal-oil co-refining residues has the potentials to prepare activated carbon due to its high content of carbon.Based on the analysis of the properties of residues,the oal-oil co-refining residues based activated carbon was prepared via the method of KOH activation.The effect of the alkali-carbon ratio,heating rate,carbonization temperature,carbonization time,activation temperature,activation time and other factors on the specific surface area of the residue-based activated carbon was investigated.The specific surface area of the prepared activated carbon is up to 2345 m2/g.The adsorption characteristics of the prepared the oal-oil co-refining residues based activated carbon of metal ions and dye were investigated.The experimental results displayed that the adsorption properties of activated carbon is related to the washing method of the product after pyrolysis,the specific surface area of the oal-oil co-refining residues based activated carbon,the content of alkaline oxides,the pH and initial concentration of the metal ions and dye solution,adsorption time and the temperature.The higher the content of alkaline oxides on the surface of activated carbon has the better adsorption effect for metal ions.The larger the specific surface area of the oal-oil co-refining residues based activated carbon,the better the absorptivity of the dye.The adsorption of metal ions and dyes on the oal-oil co-refining residues based activated carbon was affected by the pH value of the metal ions and dyes solution.The higher the pH is,the higher the adsorption capacity of metal ions has.The solubility of dyes is different with different pH values,which results in different adsorption capacity of activated carbon for dyes.The maximum adsorption capacities of Cr3+ Cu2+,Ni2+,rhodamine B,methyl orange,and methylene blue are 138.97 mg/g,160.68 mg/g,119.23 mg/g,2485.78 mg/g,2100.76 mg/g,1031.78 mg/g,respectively.The results of adsorption kinetics and adsorption thermodynamics show that both the adsorption of metal ions and dyes by activated carbon are single-layer chemical adsorption,which are endothermic process with increased entropy.The higher temperature is beneficial to adsorption.The influence of pH value of solution and alkaline oxide content on the adsorption capacities of metal ion indicates that the adsorption of metal ions by activated carbon is mainly through ion exchange and precipitation.The adsorption of dye by activated carbon is caused by π-π interaction and micropore filling.The possibility of coal-oil co-refining residue-based activated carbon as a catalyst supporter for coal-oil co-refining was explored-Although FeS is contained in the water-washed residue-based activated carbon,it has no catalytic ability.The catalytic activity is greatly improved after FeOOH is immolized.The effects of the specific surface area of the catalyst,the washing method of the product after pyrolysis,and the content of FeOOH on the conversion of coal and asphaltene as well as oil yield were investigated.The results showed that the ash content in the activated carbon has an inhibitory effect on the catalytic performance.The specific surface area of the coal-oil co-refining reaction catalyst has little effect on the catalytic activity of the coal-oil co-refining reaction catalyst for coal-oil co-refining reaction.The pore structure of the coal-oil co-refining reaction catalyst has a certain effect on the conversion of asphaltene of the coal-oil co-refining reaction.The acid-washed activated carbon is more suitable as a catalyst carrier.