| The chloroprene generated by acetylene method or1,3-butadiene method is themonomer of chloroprene rubber. Due to security problems in acetylene method, manyforeign countries use1,3-butadiene method to produce chloroprene rubber. However,considering the raw materials, technology and other factors, domestic still adopt theacetylene method.Dimerization of acetylene has long been catalyzed by a Nieuwland catalystcomposed of CuCl and KCl or NH4Cl in aqueous solution on an industrial scale. Forproblems of low conversion rates, side reactions and low selectivity of target product inaqueous system, DMF was usesd as the solvent for non-aqueous catalyst which is addedionic liquids and ligands to improve the acetylene conversion and MVA selectively. Theeffect of ionic liquids, A dosage, reaction temperature and ligands on catalystperformance were investigated.The results showed that imidazolium-based ionic liquids were conducive to thestability of catalyst and prolong the catalyst life. Some ionic liquids even could improvethe acetylene conversion especially A. Reaction temperature has a great influence ondimerization of acetylene, only suitable temperature conducive to the formation of MVA.When relative density of CuCl is1511kg/m3, CuCl/A molar ratio is30:1, space velocityof acetylene is216h-1, reaction temperature is88℃, the acetylene conversion reached32.4%and the selectivity of MVA averaged93.7%. If pyridine,2-chloropyridine,2,6-dichloropyridine and8-hydroxyquinoline were added in hereinbefore reactionconditions（CuCl/liagand molar ratio is25:1）, MVA selectively increased to97.6%,95.1%,96.6%and98.1%respectively, However, acetylene conversion were reduced.The influences of reaction temperature（8595℃） and acetylene partial pressure onreaction rate were investigated. Macrokinetics models of dimerization andcopolymerization were established and models parameters were gained by the leastsquares method. Calculated results of macrokinetics models were consistent withexperimental results. |
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