| Lignin that came from black liquor of papermaking Industry was used to prepare aromatics and fatty hydrocarbon compounds through hydrogenation liquefaction process. The experiments were carried out in a 100ml micro-autoclave to investigate the effects of reaction temperature, reaction time, the pressure of H2, the contents of NaOH, the proportion of ethanol and lignin, some solvents, catalysts on the conversion, liquid yield, light oil yield and gas yield of liquefaction. Meanwhile, the element composition, structure, functional group of lignin were analyzed by element analysis, FT-IR. The pyrolysis characteristics of lignin were investigated by TG, TG-FTIR.(1)The element analysis show that lignin is composed of C, H, O, S and the formula can express as C9H10.4O3.5S0.4. The FTIR spectrum show there were a lots of groups such as methoxy, hydroxy, guaiacyl, syringyl.(2) The pyrolysis of lignin undergoes three stages: the first stage is from 25 220℃ that mainly occurs dehydration and the weight loss is 16%. The second stage is from 220487℃ that is the main area of pyrolysis of lignin and the weight loss is 36%. At 287℃ produce the most weight loss. The third stage is from 4871000℃ that is the deep pyrolysis. The FT-IR spectrums of the pyrolysis gas show that the pyrolysis of lignin produces some gas such as H2O, CO, CO2, CH4, SO2 and so on.(3) In the stream of N2, TGA was used to study the pyrolysis characteristics of lignin. Four kinds of methods, Coats-redfern, Doyle, Kissinger and Distributed Activation Energy Model(DAEM), were used to determine the kinetics parameters of pyrolysis of lignin. The results indicated the kinetics parameters were different with different methods. DAEM is an efficient method to provide the good results.(5) In different conditions, the most conversion and light oil yield of hydrogenation liquefaction of lignin are about 69.8%, 56%. In the present of catalyst, the effect of liquefaction was enhanced. The catalyst can remarkably increase the yield of light oil. |
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