A series of sulfonated Zr-MCM-41 samples were synthesized by the in-situ method followed by sulfonation using sulfuric acid for the catalytic study of cellulose to 5-hydroxymethyl furfural in batch condition. All synthesized catalysts were characterized by XRD, N₂ adsorption–desorption isotherm, FT-IR, TEM, EDX, and NH₃ temperature-programmed desorption analysis. The XRD and N₂ adsorption–desorption isotherm results have confirmed that incorporated Zr⁴⁺ was substituted within the framework of silica MCM-41 with hexagonal pores. Similarly, the FT-IR and EDX results have proved that Zr-MCM-41 was sulfonated. The Brønsted acidic and Lewis acidic sites were identified by NH₃-TPD analysis. Among the sulfonated Zr-MCM-41 catalysts, S-15Zr-MCM-41 has shown 70% cellulose conversion with 16.4% selectivity of 5-hydroxymethyl furfural at 170 °C for 2 h which was higher than other catalysts. It was attributed to the high ratio of Brønsted acidic to Lewis acidic sites.

Graphic abstract

中文翻译：

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磺化Zr-MCM-41中Brønsted和Lewis酸性位点对纤维素催化合成5-羟甲基糠醛的作用

通过原位合成一系列磺化的Zr-MCM-41样品，然后使用硫酸进行磺化，以间歇方式将纤维素催化合成5-羟甲基糠醛。所有合成的催化剂都通过XRD，N ₂吸附-解吸等温线，FT-IR，TEM，EDX和NH _3程序升温脱附分析进行了表征。XRD和N ₂吸附-解吸等温线结果证实，掺入的Zr ⁴⁺在具有六边形孔的二氧化硅MCM-41框架内被取代。同样，FT-IR和EDX结果证明Zr-MCM-41被磺化。布朗斯台德酸性和路易斯酸性位点由NH ₃鉴定-TPD分析。在磺化的Zr-MCM-41催化剂中，S-15Zr-MCM-41在170°C的条件下2小时显示出70％的纤维素转化率和5-羟甲基糠醛选择性16.4％的选择性，高于其他催化剂。这归因于布朗斯台德酸与路易斯酸位的比例高。

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