Catalytic hydroliquefaction of charcoal CCB (copper, chromium and boron)-treated wood for bio-oil production: Influence of CCB salts, residence time and catalysts

摘要

Thermochemical processes offer a feasible option for wood waste management and the recovery of a variety of useful chemicals. In this paper, hydroliquefaction with the use of catalysts was optimized to provide bio-oil from CCB-treated wood by reducing gaseous emissions of copper, chromium and boron (hazardous materials). In addition, the influence of CCB salts, catalysts (Al_2O_3, Na_2CO_3, MgO and CaCO_3) and residence time on the hydroliquefaction process was investigated. For this, hydroliquefaction of charcoal obtained by slow pyrolysis of CCB-treated wood was conducted under hydrogen pressure in presence of tetralin. The results showed that CCB salts and catalysts increase the yield of bio-oil compared to hydroliquefaction of charcoal from untreated wood. It was also observed, that the use of catalysts improves the residence time during the process. Among the catalysts employed, Al_2O_3 appears to be the most effective. Furthermore Na_2CO_3 promotes the formation of gaseous species particularly CH4. Analyses of hazardous materials in charcoal residue (coke) illustrate their transfer to the bio-oil with the increase of bio-oil yield and residence time except when Al_2O_3 was using. The bio-oil obtained contains aromatic compounds.