Catalysis Research Group, Chemistry Department, College of Science, King Khalid University, Abha 61413, Saudi Arabia.
Molecules. 2022 May 14;27(10):3145. doi: 10.3390/molecules27103145.
Nickel oxide powder was prepared by simple calcination of nickel nitrate hexahydrate at 500 °C for 5 h and used as a catalyst for the oxidation of cyclohexane to produce the cyclohexanone and cyclohexanol-KA oil. Molecular oxygen (O), hydrogen peroxide (HO), t-butyl hydrogen peroxide (TBHP) and -chloroperoxybenzoic acid (-CPBA) were evaluated as oxidizing agents under different conditions. -CPBA exhibited higher catalytic activity compared to other oxidants. Using 1.5 equivalent of -CPBA as an oxygen donor agent for 24 h at 70 °C, in acetonitrile as a solvent, NiO powder showed exceptional catalytic activity for the oxidation of cyclohexane to produce KA oil. Compared to different catalytic systems reported in the literature, for the first time, about 85% of cyclohexane was converted to products, with 99% KA oil selectivity, including around 87% and 13% selectivity toward cyclohexanone and cyclohexanol, respectively. The reusability of NiO catalyst was also investigated. During four successive cycles, the conversion of cyclohexane and the selectivity toward cyclohexanone were decreased progressively to 63% and 60%, respectively, while the selectivity toward cyclohexanol was increased gradually to 40%.
氧化镍粉末通过简单的煅烧六水合硝酸镍在 500°C 下 5 小时制得，并用作环己烷氧化生成环己酮和环己醇-KA 油的催化剂。分子氧 (O)、过氧化氢 (HO)、叔丁基过氧化氢 (TBHP) 和 -氯过氧苯甲酸 (-CPBA) 在不同条件下被评估为氧化剂。-CPBA 表现出比其他氧化剂更高的催化活性。在 70°C 下，以乙腈为溶剂，使用 1.5 当量的 -CPBA 作为氧供体剂反应 24 小时，NiO 粉末对环己烷氧化生成 KA 油表现出优异的催化活性。与文献中报道的不同催化体系相比，环己烷的转化率约为 85%，KA 油的选择性为 99%，环己酮和环己醇的选择性分别约为 87%和 13%。还研究了 NiO 催化剂的可重复使用性。在连续四个循环中，环己烷的转化率和环己酮的选择性逐渐降低至 63%和 60%，而环己醇的选择性逐渐增加至 40%。
