桉木APMP制浆废液中主要有机组分的热解特性

Pyrolysis Characteristics of Main Organic Components in Eucalypt APMP Pulping Spent Liquor

采用高温静态水平管式炉对桉木碱性过氧化氢机械浆（APMP）制浆废液固形物（ASLS）及其3种主要组分,即碱木质素（AL）、多糖（PLS）与木质素-碳水化合物复合体（LCC）在400～800℃进行快速热解,利用GC、GC/MS、FT-IR和SEM等手段,分析了各相热解产物组成与分布规律.结果表明,AL对ASLS热解液相产物得率影响较大,PLS对气相产物与固相产物得率的影响较大.ASLS热解产生H2能力较强而与组分热解关系不大,高温阶段PLS热解生成CO能力显著提高,AL热解产生烃类化合物的能力明显高于其他组分.ASLS热解液相产物中的苯环化合物主要源自于AL热解产生,酚类与稠环化合物主要源自于AL和LCC组分热解产生,而酮类、呋喃类和酸类则是由AL、LCC和PLS热解后共同产生.ASLS、AL、PLS和LCC热解半焦表观形貌的差异比较明显.

The eucalypt alkaline peroxide mechanical pulp （APMP） spent liquor solid （ASLS） and its three major organic components, i.e., alkali lignin （ AL）, polysaccharide （PLS） and lignin-carbohydrate complexes （ LCC ）, were rapidly pyrolyzed at the temperature from 400 ℃ to 800 ℃ through a tubular furnace. The composition and distribution of the pyrolysis products were determined by gas chromatography （GC）, gas chromatography coupled with mass spectrometry （GC/MS）, .Fourier transforms infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）, respectively. It was found that AL showed a significant effect＇on the yield of liquid products while PLS exhibited a remarkable influence on the yield of solid and gas products as ASLS was pyrolyzed. The yield of H2 was as high as ASLS was pyrolyzed. It indicated no relation with the contents of AL, LCC and PLS. A large amount of CO was generated as PLS was pyrolyzed at high temperature. In contrast to ASLS, LCC and PLS, more hydrocarbon was generated as AL was pyrolyzed. Aromatics of ASLS pyrolysis liquid products were mainly from AL. And the pyrolysis of AL and LCC should be responsible for the generation of phenols and PAHs. Ketones, furans and acids were attributed to the pyrolysis of AL, LCC and PLS. The surface morphologies of ASLS, AL, LCC and PLS pyrolysis char were significantly different.