| Dimethyl Carbonate (DMC) is an environmentally friendly chemicals. The present paper has studied the factors influencing the reaction, deactivation, regeneration, and stability of PdCh-CuCk-KOAc/AC catalyst. Furthermore, the scale-up experiment of industrial single-tube has been investigated.Effect of pretreatment condition, reaction temperature, molar ratio of the feeds, reaction pressure and water content in the feeds on the properties of synthesis reaction for DMC have been studied.Treating the catalyst with methanol solution of methyl chloro-acetate can improve the activity and stability. The suitable concentration of methyl chloro-acetate and pretreatment temperature have been determined to be 15% and 220 C respectively. The suitable reaction temperature is within a range of 140-160 C. The optimal molar ratio of MeOH, CO and 62 is 4:2:1. Reaction pressure has a significant effect on gas-phase catalytic synthesis of DMC. The optimal pressure is 0.3MPa. Under such conditions, the STY of DMC is 785g/L-cat h. By means of XPS and XRD analysis, the reason for deactivity of the catalyst under high pressure is the formation of copper oxalate crystalline. In addition, high water content in the feed greatly promotes the complete oxidation reaction of CO and methanol.Therefore, the molar percentage of water in the feed should be controlled less than 1%.The deactivated and regenerated catalysts have been studied by means of XPS, XRD, AAS, BET, TG-DTA, etc. It is shown that the active centers are Pd2+ and Cu+ for synthesis of DMC by gas-phase oxidation carbonylation of methnol over PdCl2-CuCl2-KOAc/AC. Treating the catalyst with chloro-organic compounds can change the ratio of Cu2+/Cu+ on the surface of the catalyst. The synergistic effect between Pd and Cu can complete the oxidation -reduction cycle between Pd2+/Pd?and Cu2+/Cu+. The loss of Cl- anion is one of the main reason for the catalyst deactivation. The activity will be restored by treatment with chloro-organic compounds. The generation of Cu2(OH)3Cl 2H2O crystalline, loss of Pd component, carbon deposition and aggregation of metal particles are the main reasons for the deactivation of the catalyst..The effect of reaction temperature, load of active species, and regeneration atmosphere on the service time of the catalyst is studied. The result shows that the catalyst stability decreases with the rising of reaction temperature, which results rapid loss of the active species. The catalystactivity and selectivity can be improved with the increasing of KOAc load because of increasing chlorine content on the surface of the catalyst. The catalyst activity is restored when the regeneration is performed at oxygen atomosphere because Pd particle in aggregation state can be converted to Pd2+ in dispersion state. The catalyst activity decreases greatly when the regeneration is performed at CO atomosphere because Pd and Cu ion can be reduced.On the basis of laboratory experiment, industrial scale-up single tubular experiment has been done. The experimental result shows that industrial feeds purity can meet the needs of the chemical reaction. Surface structure and pore diffusion of the catalyst have a great influence on the reaction. So the change of the pore structure and the method of preparing catalyst should be further studied. Sulfide in methyl chloro-acetate used in both pretreatment and regeneration process, and ferrous compounds are two main reasons for the catalyst deactivation in the single tubular experiment.
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