反应温度对Mo/Al2O3催化碱木质素生物油加氢脱氧影响研究
Effect of reaction temperature on Mo/Al2O3 catalytic hydrodeoxygenation of alkali lignin bio-oils
曹鹤 1杨天华 1李秉硕 1张海军 1佟瑶1
作者信息
- 1. 沈阳航空航天大学能源与环境学院辽宁省清洁能源重点实验室,辽宁沈阳 110136
- 折叠
摘要
碱木质素作为重要的工业木质素来源,通过水热液化技术可以保留其中芳环结构,用于制备生物燃料中芳烃组分.在反应过程中,温度对生物油产率和组分影响较大.重点研究了在Mo/Al2O3催化碱木质素水热液化制备生物油过程中,反应温度对油产率和芳烃产率影响.研究结果表明,随着温度升高,生物油产率先增加后减少,在280℃时获得最高生物油产率.生物油的O/C比随温度升高持续下降,最低可达0.22,同时H/C比则持续增加,最高可达1.14.此外,高位热值也持续增加,最大值可达30.41 MJ/kg,温度的升高促进了生物油燃料特性的提升.然而,温度的升高对生物油中芳烃的富集不利,温度越高,生物油中芳烃的相对含量越低,而酚类化合物的含量越高.在260 ℃和添加质量分数15％的Mo/Al2O3催化剂条件下,芳烃的相对含量达到最大值34.1％,此时芳烃产物中对甲苯的选择性高达97.7％,芳烃产物富集效果最好.
Abstract
Alkali lignin,an important source of industrial lignin,can be used for producing aromatic com-ponents in biofuels while retaining its aromatic ring structure through hydrothermal liquefaction technology.The temperature during the reaction process significantly influences the bio-oil yield and composition.This study investigates the impact of reaction temperature on the oil yield and aromatics yield in the preparation of bio-oil through hydrothermal liquefaction of alkali lignin catalyzed by Mo/Al2O3.The study's findings re-vealed that the oil yield initially increased and then decreased with increasing temperature,reaching its highest value at 280 ℃.As the temperature increased,the O/C ratio of the bio-oil continuously decreased to a minimum of 0.22.In contrast,the H/C ratio steadily increased to a maximum of 1.14.Additionally,the high calorific value steadily increased to a maximum of 30.41 MJ/kg.These results indicated that higher temperatures contributed to improving the fuel properties of the bio-oil.However,increasing the temperature was not conducive to the enrichment of aromatic components in the bio-oil.The higher the temperature,the lower the relative content of aromatic compounds and the higher the content of phenolic compounds in the bio-oil.The study observed that the relative content of aromatics reached its peak value of 34.1％at 260 ℃ when 15％Mo/Al2O3 was added as a catalyst.At this temperature,the selectivity to toluene in the aromatics product was as high as 97.7％,indicating the optimal enrichment of aromatics.In summary,the study dem-onstrates that the temperature during the hydrothermal liquefaction process of alkali lignin affects both the bio-oil yield and composition.While higher temperatures enhance the oil yield and fuel properties of the bio-oil,they also reduce the relative content of aromatic compounds.The addition of Mo/Al2O3 as a catalyst at an appropriate temperature can promote the enrichment of aromatics,where toluene is the dominant product.
关键词
碱木质素/水热液化/生物油/芳香烃/加氢脱氧/反应温度Key words
Alkali lignin/Hydrothermal liquefaction/Bio-oil/Aromatic hydrocarbons/Hydrodeoxy-genation/Reaction temperature引用本文复制引用
基金项目
国家自然科学基金(52176195)
辽宁省"兴辽英才计划"项目(XLYC200512)
出版年
2024
国家科技期刊平台
NSTL
万方数据