竹浆黑液木质素热解油分子尺寸的量子化学计算及其分布特性研究

Quantum Chemical Calculation of Molecular Size and Distribution Characteristics of Pyrolysis Oil from Bamboo Kraft Lignin

关键词:  黑液木质素  催化热解  热解油  量子化学计算

Key Words:black liquor lignin  catalytic pyrolysis  pyrolysis oil  quantum chemical calculation

摘要:黑液木质素主要以生物质制浆造纸过程中的固体残渣形式存在，是一种潜在的生产高价值化学品的原料。本研究采用异核单量子相干核磁共振技术（HSQC-NMR）表征了竹浆黑液木质素和热解重油，并用量子化学计算方法研究了黑液木质素在600℃高温条件下热解油组分的分子尺寸。结果表明，竹浆黑液木质素由G型、S型和H型木质素单元构成，热解油的主要组分为酚类、酮类、醇类和醚类化合物。热解油小分子组分的y维度与动力学直径主要集中在6.5~8.4 Å区域。根据量子化学计算结果，木质素催化热解制备高品质液体燃料可选用孔径尺寸在6.5~8.4 Å的分子筛催化剂。

Abstract:Black liquor lignin mainly exists in the form of solid residues in the biomass pulping process， is a potential feedstock for the production of high-value chemicals. In this study， heteronuclear single quantum coherence nuclear magnetic resonance （HSQC-NMR） was used to characterize the lignin and pyrolysis heavy oil of bamboo kraft black liquor， and the molecular size of the pyrolysis oil fractions of black liquor lignin at high temperature of 600℃ was investigated by quantum chemical calculations. The results showed that the lignin of bamboo kraft black liquor mainly consisted of G-type， S-type and H-type lignin units， and the main components of pyrolysis oil were phenols， ketones， alcohols and ethers. The y-dimension and kinetic diameters of small molecules of pyrolysis oil were mainly concentrated in the region of 6.5~8.4 Å. According to quantum chemical calculations， molecular sieve catalysts with pore sizes in the range of 6.5~8.4 Å could be used for lignin-catalyzed cracking to prepare high-quality liquid fuels.