Abstract Sulfonic acid functional strong acidic catalysts are largely used in various chemical reactions. However, in many reactions with water as product, the catalytic activity and selectivity are unsatisfactory, because hydrophilic acid sites of SO3H would suffer from acidity decreasing and some hydrolysis side reactions would occur via water adsorption. Herein, a novel hydrophobic arenesulfonic acid functionalized biochar was successfully prepared for the first time by one-pot diazo reduction method of biochar with amino-arenesulfonic acid (such as, 4-aminbenzenesulfonic acid, 4-amino-1-naphthalenesulfonic acid, 8-amino-1-naphthalenesulfonic acid, 4-amino-3-hydroxy-1-naphthalenesulphonic acid). It has a large specific surface area of 200–400 m2/g, a hydrophobic network with water contact angle higher than 120° and a higher concentration of sulfonic acid over 1.0 mmol/g. Moreover, the hydrophobicity-oleophilicity and acidity are increased with the arene length and grafting amount of arenesulfonic acid. In the esterification reaction of fatty acid with methanol as well as the transesterification reaction of glycerol trioleate with methanol for the production of biodiesel, the sulfonated biochar shows a higher conversion of 96.7% for esterification and 86.3% for transesterification compared with amberlyst-15 (86.7%, 39.9%) and traditional sulfonation biochar-SO3H (27.4%, 32.6%). In the alkylation reaction of 2-methylfuran with cyclopentanone for the production of high-density biofuel, its catalytic efficiency with target product yield of 76.1% is higher than that of amberlyst-15 (50.2%) and traditional sulfonation biochar-SO3H (13.2%), because of its hydrophobicity and strong acidity. Furthermore, the catalyst is stable and shows an excellent cycle performance after 6 runs. The successful preparation of hydrophobic biochar-based acidic catalysts not only provides a new way for high-value utilization of biochar, but also eliminates the negative effect of water on many catalytic reactions.

中文翻译：

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磺酸功能化疏水介孔生物炭：设计、制备和酸催化性能

摘要 磺酸功能强酸性催化剂广泛用于各种化学反应。然而，在许多以水为产物的反应中，催化活性和选择性并不令人满意，因为SO3H的亲水性酸位会受到酸度降低的影响，并且会通过吸水发生一些水解副反应。在此，首次采用氨基芳烃磺酸（如4-氨基苯磺酸、4-氨基-1-萘磺酸、8-氨基苯磺酸）对生物炭进行一锅重氮还原法，首次成功制备了新型疏水性芳烃磺酸功能化生物炭。氨基-1-萘磺酸、4-氨基-3-羟基-1-萘磺酸）。它具有200-400平方米/克的大比表面积，水接触角大于 120° 的疏水网络和超过 1.0 mmol/g 的更高浓度的磺酸。此外，疏水性-亲油性和酸度随着芳烃长度和芳烃磺酸接枝量的增加而增加。在脂肪酸与甲醇的酯化反应以及三油酸甘油酯与甲醇的酯交换反应生产生物柴油中，与 amberlyst-15 (86.7) 相比，磺化生物炭的酯化转化率为 96.7%，酯化转化率为 86.3%。 %, 39.9%) 和传统的磺化 biochar-SO3H (27.4%, 32.6%)。在2-甲基呋喃与环戊酮制备高密度生物燃料的烷基化反应中，其催化效率达到76.1%，目标产物收率高于amberlyst-15(50. 2%) 和传统的磺化 biochar-SO3H (13.2%)，因为它具有疏水性和强酸性。此外，催化剂稳定并在 6 次运行后显示出优异的循环性能。疏水性生物炭基酸性催化剂的成功制备不仅为生物炭的高价值利用提供了新途径，而且消除了水对许多催化反应的负面影响。