Abstract The effect of competitive adsorption on the catalytic performance of H3PMo12O40@C catalyst for producing 2-nitro-4-methylsulfonylbenzoic acid (NMSBA) from the oxidation of 2-nitro-4- methylsulfonyltoluene (NMST) by oxygen in acetic acid has been investigated. Six kinds of acids were added into the impregnation solution as competitive adsorbates for phosphomolybdic acid in the preparation of H3PMo12O40@C catalyst. H2SO4, HCl, HNO3, CH3COOH and H2C2O4 are beneficial to improving the catalytic activity of the H3PMo12O40@C catalyst. The corresponding optimum impregnation concentrations for H2SO4, HCl, HNO3, CH3COOH and H2C2O4 are 0.4, 0.3, 0.3, 1.0 and 0.3 mol L−1, respectively. The addition of H3PO4 exerts a negative effect on the catalytic capability of H3PMo12O40@C catalyst. The results of TEM characterization show that good dispersion of H3PMo12O40 on the surface of the H3PMo12O40@C catalyst is beneficial to ameliorating the catalytic ability of H3PMo12O40@C catalyst in the production of NMSBA from NMST by oxygen in acetic acid. The results of NH3-TPD indicate that the acidity of the H3PMo12O40@C also favors the improvement of the catalytic capability of H3PMo12O40@C in the oxidation of NMST to NMSBA.

中文翻译：

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竞争性吸附物对 H3PMo12O40@C 在 NMST 氧化为 NMSBA 中催化活性的影响

摘要 研究了竞争吸附对 H3PMo12O40@C 催化剂在乙酸中氧气氧化 2-硝基-4-甲基磺酰基甲苯 (NMST) 制备 2-硝基-4-甲基磺酰基苯甲酸 (NMSBA) 的催化性能的影响。 . 在H3PMo12O40@C催化剂的制备过程中，将六种酸作为磷钼酸的竞争性吸附剂加入浸渍液中。H2SO4、HCl、HNO3、CH3COOH和H2C2O4有利于提高H3PMo12O40@C催化剂的催化活性。H2SO4、HCl、HNO3、CH3COOH 和 H2C2O4 的相应最佳浸渍浓度分别为 0.4、0.3、0.3、1.0 和 0.3 mol L-1。H3PO4 的加入对 H3PMo12O40@C 催化剂的催化能力产生负面影响。TEM表征结果表明，H3PMo12O40在H3PMo12O40@C催化剂表面的良好分散有利于提高H3PMo12O40@C催化剂在乙酸中的氧气由NMST生产NMSBA中的催化能力。NH3-TPD 的结果表明，H3PMo12O40@C 的酸性也有利于提高 H3PMo12O40@C 在将 NMST 氧化为 NMSBA 的催化能力。