中文摘要：

用不同催化剂微波裂解棉秆,研究了催化剂对裂解产物产率和裂解油组分的影响.结果表明,NaOH,Na2CO3和H3PO4均可降低液体产物产率、增加固体产物和气体产物产率.液体产率由不加催化剂时的28.9%分别降到23.8%,22.1%和26.7%.不加催化剂时微波裂解油中主要组分包括羟基丙酮、糠醛、愈创木酚及4-甲基愈创木酚,加入NaOH和Na2CO3均能显著提高羟基丙酮含量,羟基丙酮含量由35.24%提高到约50%.加入H3PO4可明显促进糠醛和4-甲基愈创木酚生成,糠醛＋4-甲基愈创木酚含量提高到约70%,而不加催化剂时其含量均在10%以下,且H3PO4抑制羟基丙酮生成,并显著简化微波裂解油组分.提出了由纤维素、半纤维素和木质素分别直接裂解生成羟基丙酮、糠醛和4-甲基愈创木酚的可能的反应路径.

英文摘要：

The microwave pyrolysis of cotton stalk was investigated to determine the effects of three different catalysts on the yields of product and the components of bio-oil. Research results showed that NaOH, Na2CO3 and H3PO4 can all decrease the yield of liquid and increase the yields of solid and gas, the liquid yield decreased to 23.8%, 22.1% and 26.7% from 28.9% without catalysts, respectively. The main components of bio-oil from microwave-assisted pyrolysis of cotton stalk without catalysts are acetol, furfural, guaiacol, and 4-methyl-guaiacol. Both NaOH and Na2CO3 can remarkably favor the formation of acetol. The relative concentration of acetol increased to about 50% from 35.24%. H3PO4 can significantly promote the formation of furfural and 4-methyl-guaiacol. The total relative peaks of these two components（furfural and 4-methyl-guaiacol） were up to 70%. However, the relative concentrations of furfural and 4-methyl-guaiacol in bio-oil from microwave-assisted pyrolysis of cotton stalk without catalysts was less than 10%. Meanwhile, H3PO4 can inhibit the formation of acetol. Moreover, H3PO4 addition can greatly simplify the bio-oil components. The possible formation pathway of acetol, furfural and 4-methyl-guaiacol for the direct conversion of the cellulose unit, the xylan unit and the coniferyl alcohol were proposed, respectively.