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的稳定性.本文以传统均相Co盐催化剂的多相化为出发点，制备了Co掺杂SAPO-5与分子筛催化剂(Co-SAPO-5)，考察了Co掺杂量对催化剂结构、表面性质以及氧气选择性氧化环己烷反应性能的影响.结果表明，一部分Co进入分子筛骨架，同时有少量Co以氧化钴形式高度分散在SAPO-5表面. Co掺杂对SAOP-5催化剂比表面积没有显著影响，但可使其孔体积减小.相反， Co掺杂可以提高SAOP-5分子筛表面B酸性位数量和总酸量.活性测试结果表明，环己烷转化率随着Co-SAPO-5催化剂中Co含量的增加而增加，但KA油选择性在转化率高于6.3%时急剧下降.还考察了反应温度、反应时间、初始氧气压力和催化剂用量对Co-SAPO-5分子筛催化剂性能的影响，得到了最优反应条件.以Co-SAPO-5-0.2(Co/Si摩尔比为0.2)分子筛为催化剂时， KA油总收率最高可达7.8%.另外， Co-SAPO-5催化剂在环己烷氧化反应中显示出很好的稳定性， Co-SAPO-5-0.2催化剂套用6次后活性几乎没有变化.

Silicoaluminophosphate (SAPO) molecular sieves doped with cobalt (Co‐SAPO‐5) were synthesized hydrothermally with different concentrations of Co. Each sample was characterized by X‐ray dif‐fraction, N2 adsorption‐desorption, scanning electron microscopy, ultraviolet‐visible spectroscopy, temperature‐programmed desorption of NH3 (NH3‐TPD), and infrared spectrascopy of adsorbed pyridine (Py‐IR). The results showed that Co was highly dispersed in the Co‐SAPO‐5 samples. In addition, a part of the Co content had been incorporated into the SAPO‐5 framework, while the remainder existed on the surface as extra‐framework Co. The surface areas of the Co‐SAOP‐5 sam‐ples were similar to the SAPO‐5 sample. However, the pore volumes of the Co‐SAOP‐5 samples were lower than that of the SAOP‐5 sample. As the concentration of Co increased, the pore volume gradu‐ally decreased because extra‐framework cobalt oxide was present on the catalyst surface. NH3‐TPD and Py‐IR results revealed that the amount of Br?nsted acid and the total amount of acid for the Co‐SAPO‐5 samples were higher than that for the SAPO‐5 sample. These values were also higher for samples with higher Co content. The catalytic activity of the Co‐SAPO‐5 samples was evaluated for the oxidation of cyclohexane with molecular oxygen. When Co was added to the SAPO‐5 catalyst, the catalytic activity of the Co‐SAPO‐5 catalysts improved. In addition, the conversion of cyclohexane increased as the Co content in the Co‐SAPO‐5 catalysts increased. However, with a high conversion of cyclohexane (>6.30%), the total selectivity of cyclohexanone (K) and cyclohexanol (A) decreased sharply. The K/A ratio ranged from 1.15 to 2.47. The effects of reaction conditions (i.e., reaction temperature, reaction time, initial oxygen pressure, and the catalyst amount) on the performance of the Co‐SAPO‐5 catalysts have also been measured. Furthermore, the stability of the Co‐SAPO‐5 cat‐alyst was explored and found to be good for the selective oxidation of cyclohexane by molecular oxygen.