Study On Catalytic Dehydrogenation Performance Of Hydrophobic Catalyst And Piatinum Metal Catalyst In The Tail Chloride At Low Temperature

Chlor-alkali industry is an important component of the national economy,its products are widely used in the field of various industries. Traditionalchlorine electrolysis process will produce large amounts of chlorine-containingexhaust gas (referred to as tail chlorine). With the continuous development ofchlor-alkali industry and production of chlorine revelent products, tail chlorineproduction also increased every year. The component of tail chlorine is verycomplex and if the volume content of hydrogen excess4%, there will be thedanger of explosion. The traditional methods can not fundamentally solve theproblem of tail chlorine containing hydrogen. The safety use of tail chlorinecontaining corrosive chlorine and explosive hydrogen has become a problem tobe solved.This experiment simulated industrial components of tail chlorinedistribution:Chlorine (65～80%),oxygen (8～10%), hydrogen (1.5～4%) and asmall amount of nitrogen. The catalysts used in the experiments were preparedwith impregnation method. The experiment were divided into two parts: the research on dehydrogenation performance of hydrophobic catalyst and platinummetal catalyst in tail chlorine. The experiment used homemade fixed reactor toevaluate the performance of catalysts and explored the influence of metalloading, reduction temperature, quantity of PTFE, additive type, reactiontemperature on the catalytic dehydrogenation performance. The catalysts werecharacterized by XRD、FTIR and N2-adsorption, to observe the microstructurechange of catalysts before and after supported and reaction. From thisexperiment, there are following conclusions:1. Hydrophobic catalyst Ag/PTFE/C catalysts showed high catalyticdehydrogenation performance activity and oxygen-hydrogen selectivity. Thecatalyst added PTFE had hydrophobicity and alleviated the water poisoningproblem to some extent.2. Preparation and reaction conditions have great influence on performanceof catalyst. For Ag/PTFE/C catalyst, under1.5%of Ag loading, C: PTFE=2:1,250℃reduction temperature,70℃reaction temperature, the catalyst achievedthe best dehydrogenation performance. The overall hydrogen conversion rateand selectivity of oxygen-hydrogen reaction of Ag/PTFE/C could respectivelyreached77.60%and80.72%.3. Platinum metals catalysts are expensive. But its catalytic activity andoxygen-hydrogen selectivity were better than Ag/PTFE/C, and catalyticperformances were stable. For Ce/Pt/SiO2catalyst, under1.0%of Pt loading,2.0%of additive Ce(NO3)3,350℃reduction temperature,60℃reaction temperature, the catalyst achieved the best dehydrogenation performance. Theoverall hydrogen conversion rate and selectivity of oxygen-hydrogen reaction ofCe/Pt/SiO2could respectively reached91.99%and83.12%.4. For platinum metal catalyst, the add of additives optimized the catalyticproperties of the catalyst to some extent. The experiment found that thedehydrogenation performance of catalysts added La(NO3)3or Ce(NO3)3werebetter under the same additives content and their catalytic dehydrogenationperformance were better.5. After the Ag/PTFE/C and platinum metal catalysts were characterizedby XRD, FIRT,and nitrogen adsorption, it showed that: the dispersion of activeingredient, the specific surface area, pore volume and skeleton structure of thecarrier have not much changed before and after the dehydrogenation reaction. Sothe two kinds of catalysts can be used in the dehydrogenation reaction of tailchlorine.