Key Laboratory of Clean Energy of Liaoning, College of Energy and Environment,Shenyang Aerospace University

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30.41MJ/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。

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.

国家自然科学基金资助项目(52176195);辽宁省“兴辽英才计划”资助项目(XLYC200512)

曹鹤,杨天华,李秉硕,等.反应温度对Mo/Al2O3催化碱木质素生物油加氢脱氧影响研究[J].能源环境保护,2024,38(2):114-122.

CAO He, YANG Tianhua, LI Bingshuo, et al. Effect of reaction temperature on Mo/ Al2O3 catalytic hydrodeoxy⁃genation of alkali lignin bio-oils[J]. Energy Environmental Protection, 2024, 38(2): 114-122.