Catalytic Esterification Using Solid Acid Carbon Catalysts Synthesized by Sustainable Hydrothermal and Plasma Sulfonation Techniques
Catalytic Esterification Using Solid Acid Carbon Catalysts Synthesized by Sustainable Hydrothermal and Plasma Sulfonation Techniques
复制标题
DOI：
10.1021/acs.iecr.2c00086
复制
发表时间：
2022-03
期刊：
影响因子：
--
通讯作者：
Sarada Sripada;J. Kastner
中科院分区：
文献类型：
--
作者：
Sarada Sripada;J. Kastner
固体酸碳催化剂是由粒状（GAC）和整体（ACM）形式的木质活性炭使用初始润湿法和等离子体或水热法在0.62：1至1.75：1 [v/w，mL/g]的磺化剂：碳比率下合成的，显著低于常用的比率10：1（6-16倍更低）。然而，酯化率和产率与用过量浓硫酸和商业酸性树脂产生的催化剂相当。采用多种方法确定了催化剂的酸中心，并通过2-羟基异丁酸的间歇酯化反应考察了催化剂的催化活性。水热磺化的GAC和ACM产生的反应速率和酯产率与商业Amberlyst-15（150 °C，lh）相当。室温等离子体（Ar/H2O蒸气，10-15分钟）成功地磺化GAC和ACM，但由于较低的酸位点密度而产生较低的酯产率。反应和再利用研究表明，水热初湿法和等离子体磺化法可以从可再生生物质中可持续地生成固体酸碳催化剂，用于催化升级生物基有机酸。
Solid acid carbon catalysts were synthesized from wood activated carbon in granular (GAC) and monolith (ACM) forms using incipient wetness and plasma or hydrothermal methods at sulfonation agent:carbon ratios of 0.62:1 to 1.75:1 [v/w, mL/g], significantly lower than a commonly used ratio of 10:1 (6–16× lower). Yet, esterification rates and yields were comparable to those of catalysts generated with excess concentrated sulfuric acid and commercial acid resins. Acid sites were confirmed by multiple methods, and catalytic activity was investigated by batch esterification of 2-hydroxyisobutyric acid. Hydrothermally sulfonated GAC and ACM generated reaction rates and ester yields comparable to commercial Amberlyst-15 (150 °C, 1 h). Room temperature plasma (Ar/H2O vapor, 10–15 min) successfully sulfonated GAC and ACM but generated lower ester yields, due to lower acid site density. Reaction and reuse studies suggest the hydrothermal incipient wetness and plasma sulfonation methods can sustainably generate solid acid carbon catalysts from renewable biomass for catalytic upgrading biobased organic acids.