Synthesis Of Nitrogen Doped Mesoporous Carbons And Their Application In Acetylene Hydrochlorination

Polyvinyl chloride(PVC) is one of the most widely used engineering plastics, which can be applied in various aspects. As we all know, more than 70% of vinyl chloride monomer(VCM) is produced through the acetylene hydrochlorination reaction owing to the energy structure of China by using of toxic Hg Cl2/AC catalysts. It is imperative to explore efficient and low-cost mercury-free catalysts for acetylene hydrochlorination since it has become the bottle-neck problem for the industry of PVC as the global merury limited politics has been released and emphasis on environmental issues. In this paper, we studied the application of nitrogen doped carbons and Ru-based catalysts as non-mercury catalysts for acetylene hydrochlorination. Major conclusions of this article are listed below:1. The structure, surface properties and catalytic performance in acetylene hydrochlorination of three activated carbons which were produced by various resources and two mesoporous carbons prepared by different templates were investigated. The initial activities showed as MC > AC-Coal > AC-Coconut > AC-Wood > OMC due to the volume of catalysts, while MC shows a poor stability. However, the intrinsic activity of MC based on the mass of catalysts is the highest, followed by OMC, which are both higher than activated carbons. The ash of AC are not active sites and the decrease of ash content can improve the catalytic activity in acetylene hydrochlorination, effectively.2. Nitrogen modifies mesoporous carbons were prepared by an in-situ method using urea as nitrogen source, post modification by urea and ammonia gas, and copolymerization of EDA and CTC, and the effect of the nitrogen introduction on the catalytic performance in in acetylene hydrochlorination were studied. The synthesis of nitrogen doped ordered mesoporous carbon(N-OMC) by an in-situ carbonization of urea makes 3.6 wt% nitrogen was doped with more than 70% percent N was incorporated into the carbon framework as quaternary N species. Moreover, the N-OMC prepared by copolymerization of EDA and CTC can get a 15-20% nitrogen content. The introduction of nitrogen can significantly enhance the catalytic performance.3. The nitrogen species and Ru nanoparticles were simultaneously introduced into the structure of mesoporous carbon, and study the effect of nitrogen on the catalytic performance to the Ru-based catalysts. The introduction of nitrogen can significantly enhance the activities of semi-embeded Ru-carbon catalysts, N and Ru are both active sites. For loaded catalysts, the introduced catalysts can improve the dispersion of Ru metal, but the nitrogen effect on the catalytic performance in acetylene hydrochlorination of Ru/OMC is limited.