To implement mercury pollution prevention and control requirements and address the toxicity and pollution issues of traditional mercury catalysts in the calcium carbide-acetylene method for vinyl chloride synthesis, it is crucial to develop highly efficient and stable mercury-free catalysts suitable for existing processes, overcoming current limitations such as low activity and poor stability of available alternatives. Using pre-treated coal-based activated carbon as the carrier, non-precious metal copper as the main active component, and phosphoric acid and N-methylpyrrolidone as additives, a mercury-free catalyst was prepared, and its activity was evaluated in a fixed-bed reactor. The results show that under the reaction conditions of 100°C, an empty-bed contact time of 51 h-1, and n(HCl)/n(C2H2)=1.05, the mercury-free catalyst exhibited excellent catalytic performance. During a 196-hour catalyst test operation, the acetylene conversion reached 98.1%, and the vinyl chloride selectivity reached 99.29%. 为落实汞污染防控要求,攻克电石乙炔法合成氯乙烯传统汞催化剂的毒性与污染难题,针对现有无汞催化剂活性低、稳定性差等问题,研发适配现有工艺的高效稳定无汞催化剂至关重要。以预处理后煤质活性炭为载体,非贵金属铜为主要活性组分,磷酸和N-甲基吡咯烷酮作为助剂,制备无汞催化剂,在固定床反应器上评价该催化剂活性。结果表明,在反应温度100°C、空速51 h-1、n(HCl)/n(C2H2)=1.05的反应条件下,制备的25%Cu-3%Bi-4%Ce-7%H3PO4/NMP-AC无汞催化剂表现出优异的催化性能,催化剂测试运行300 h,乙炔转化率≥80%,氯乙烯选择性达99.29%。
Yanfen et al. (Wed,) studied this question.