Acetylene dimerization catalyzed by Nieuwland catalyst for the production of monovinylacetylene (MVA) is the crucial step for the manufacture of chloroprene from acetylene. The influence of the additives
DL-alanine content
acetylene gas hourly space velocity and internal diameter of the gas distributor on the reaction process were investigated. In addition
a continuous two-stage dimerization reaction was carried out. The result showed that DL-alanine would induce lower acetylene conversion and higher MVA selectivity. Higher acetylene gas hourly space velocity would cause shorter apparent residence time and strong back-mixing
which led to lower acetylene conversion and MVA selectivity. Small internal diameter of gas distributor favored the enhancement of mass transference through gas-liquid interface and the attenuation of back-mixing
which induced both high acetylene conversion and high MVA selectivity. In a continuous two-stage reaction process
both acetylene conversion and MVA selectivity kept in a high level. When the gas hourly space velocity of acetylene was 100 h-1
the acetylene conversion and MVA selectivity were 32.5% and 95.3%