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(Ga1-Al)4B2O9: controlled surface acid-base properties and catalytic behavior towards the Strecker reaction
Weilu Wang1, Zhong Fan1, Shiji Tang1
1Engineering Research Center for Waste Oil Recovery Technology and Equipment, Ministry of Education, Chongqing Technology and Business University, Chongqing, 400067, People's Republic of China. weiluwang@ctbu.edu.cn.
Abstract:
Solid bases are valuable catalysts for industrial syntheses. However, controlling the basicity of these catalysts remains a challenge. Ga4B2O9, due to μ3-O within its structure, could behave as a special solid base catalyst exhibiting intrinsic Lewis basicity. In this work, a sol-gel method was proposed to obtain continuously adjustable acidity and basicity of the metal borate catalyst (AlGa1-)4B2O9. According to the results of NH3-TPD, CO2-TPD, and the systematic experimental design, Lewis basic sites originating from GaO5 groups in (AlGa1-)4B2O9 boost the Strecker reaction rather than the Lewis acid sites related to unsaturated Al. This work illustrates the possible application of bulk-type solid solutions with simultaneous Lewis acid and base sites for the first time. A reaction mechanism has also been proposed based on the catalytic reaction results.
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