Biochar-based Sulfonated Solid Acid Adsorbed [BMIM]Cl As Catalyst Hydrolyzes Cellulose

With the depletion of fossil fuels and the highlight of environmental problems,the use of biomass as an alternative energy source becomes critical.Cellulose is a major component of biomass,and its hydrolysates have a wide range of uses in energy and chemicals.At present,the methods used to hydrolyze cellulose are:biological enzyme method,homogeneous acid method,ionic liquid method and solid acid method.Ionic liquid is a kind of emerging solvent,has great potential in cellulose hydrolysis.The sulfonating solid acid was prepared by pre-carbonizing and sulfonating bamboo powder,and adsorbed the ionic liquid 1-butyl-3-methylimidazolium chloride([BMIM]Cl)as the catalyst to hydrolyze cellulose.In this paper,solid biomass was prepared by high temperature carbonization and sulfonation of sulfuric acid in the production of common biomass as raw material.The adsorption of ionic liquid was used as catalyst for cellulose hydrolysis.The effects of reaction time and reaction temperature on the yield of reducing sugar were investigated.Specific work as follows:(1)In the experiment,bamboo was used as raw material to obtain biochar by pyrolysis at different temperatures.The solid acid was sulfonated with 98%concentrated sulfuric acid.The solid acid was ob-tained by adsorption reaction solidification of[BMIM]Cl to obtain catalyst BBn-S-IL.The content of sul-fonate on the the catalyst is related to the carbonization temperature of the biomass.The content of-SO3H in BB3-S-IL is 0.536mmol·g-1.The ability of solid acid loading[BMIM]Cl is positively correlated with the carbonization temperature.The effects of heating mode,reaction time and reaction temperature on the hy-drolysis of cellulose were also investigated.The experimental results showed that the total amount of BB7-S-IL hydrolyzed cellulose under the condition of heating temperature 150℃ and reaction time 24h TRS yield reached 22.64%,and the catalyst had good repeatability.(2)The experimental selected the common agricultural and forestry waste corn stalks,peanut shells and walnut shells were used as raw materials.After the carbonization at 700 ℃,the sulfonates were treated with concentrated sulfuric acid at 150℃ for 13h to obtain solid sulfonic acid CB-S,PB-S and WB-S.The catalysts CB-S-IL,PB-S-IL and WB-S-IL were prepared by adsorption reaction loading[BMIM]Cl on CB-S,PB-S and WB-S.The effect of reaction time and reaction temperature on the hydrolysis of cellulose was investigated systematically.The results show that the carbonized PB has abundant pore structure,and higher-SO3H content.The yield of PB-S-IL was 24.83%at the reaction temperature of 150℃ with 24h reaction time,which was significantly improved compared with PB-S and PB-S-IL had good cycle stability.