AuCl₃and A Variety Of Composite Catalyst Surface Reaction Mechanism Of Acetylene Hydrogen Chloride

Polyvinyl chloride （PVC） is one of the largest resin production in the world, with theadvantages of good mechanical strength, stable chemical property, easy processed and someother good characteristics. So PVC is applied in industry, agriculture, construction materialsand daily life widely. From a global perspective, both production and consumption of PVCgrowth steady in recent years, In terms of the situation in our country, China’s production ofPVC has become the first in the world since2007. Afterwards, although China hasencountered worldwide economic crisis and natural disasters, but the production of PVC isgrowing every year. Expected in the next period of time, the demand of PVC in China willstill have a larger growth and the production capacity of PVC will be further enhanced, whichindicate that the demand of vinyl chloride monomer will increase year by year.The softwares used in this paper was Gaussian09, and modeling, optimization andcalculation accorded to quantum chemistry density functional theory, where the calculation ofAu, Pb, Pt, Ir, Li, Na, K, Rb, Zn, Ca, Mg, Ni, Sr, Ba, Cd, Mn, Ru, Co, Hg, La, Rh, Bi, Al, Sb,Fe, Pb, Ag used LANL2DZ basis set while the calculation of H, C, N, Cl introduced wasB3LYP/6-31++G**basis set. Moreover, molecular orbital theory was used in the analysisof two-component catalyst. Adsorption energies ware calculated using the formula as follows:E_ads=E_molecule-3-E_molecule-1-E_molecule-2. Where, E_adsis the final adsorption energy; E_molecule-3 are the total energies of optimal system after metal chloride catalyst, such as AuCl₃, MgCl₂,RhCl₃and KCl, and compounds, such as HCl, C₂H₂and C₂H₃Cl, adsorbed; E_molecule-1is theenergy of metal chloride catalyst, such as AuCl₃, MgCl₂, RhCl₃and KCl, after structureoptimization; E_molecule-2is the energy of compounds, such as HCl, C₂H₂and C₂H₃Cl, afterstructure optimization.In order to judge the ability to provide electronic from co-catalyst to main catalyst, thedifference value of LUMO and HOMO orbital energy of main catalyst and co-catalyst wasinvestigated, so as to find the compounds which could improve catalyst’s electron clouddensity and enhance catalytic activity. The adsorption energy between co-catalyst andacetylene or/and vinyl chloride and the stripping energy between co-catalyst and vinylchloride were also studied. The results showed that K, Al, zinc, Cu and Ni were more suitableused as co-catalyst when AuCl₃acted as main catalyst, while K, Al and Cu were more suitable used as co-catalyst when PtCl4acted as main catalyst, and that K, Zn, Ni, Al and Cuwere more suitable used as co-catalyst when PtCl₂acted as main catalyst. Furthermore, theresults, which obtained from modification of catalyst and carrier using nitrogen, indicated thatusing ethylenediamine modified gold chloride dimers with nitrogen could increase thedistance among Au³⁺ions, resulting in increasing catalyst life of AuCl₃. The adsorptionenergy of HCl increase obviously after AuCl₃dimers with ethylenediamine complexed, butthe adsorption energies of C₂H₂, C₂H₃Cl changed little.