钾、钙和镁金属盐对生物质热解的影响

摘要

Effects of salts of potassium,calcium and magnesium(KCl,CaCl2 and MgCl2)on the pyrolytic and catalytic characteristics of pickling sylvestris and three ingredients of biomass(cellulose,hemicellulose and lignin)were investigated by using thermal gravimetric analyzer. It was found that CaCl2 serving as a pyrolytic catalyst could inhibit the condensation reaction during thermal decomposition,resulting in the“shoulder”shaped peak of the mass loss curve for hemicellulose and pickling sylvestris. In addition,compounds with low molecular weight were likely to be lost,which promoted the thermal decomposition process. MgCl2 had a good catalytic effect on the decomposition of cellulose.It gradually led to the decrease of both the maximum pyrolysis rate and corresponding pyrolysis temperature,but it had less influence on the decomposition of hemicellulose. Though the effect of KCl on the decomposition of three major ingredients of biomass was negligible,KCl showed a good pyrolytic and catalytic effect on the decomposition of pickling sylvestris.%以生物质樟子松酸洗样品以及构建生物质的纤维素、半纤维素和木质素三大组分为研究对象，通过热重分析仪研究了K、Ca和Mg金属盐(KCl、CaCl2和MgCl2)对实验样品的热解影响以及催化效果。结果表明：CaCl2的添加能抑制热解过程中的缩合反应，使得半纤维素和樟子松酸洗样品的热解失重曲线出现“肩”状峰，低分子化合物更易逃逸，促进了热分解过程；MgCl2的添加对纤维素的热解有一定的催化效果，使其最大热解失重速率以及所对应的热解温度都逐渐降低，但是对半纤维素的热解过程影响较小；KCl 对生物质三大基本组分的影响虽然很小，但对樟子松酸洗样品表现出较好的热解催化效果。