| Coke oven gas is the main byproduct of coke oven coking process,which is a good industrial fuel and chemical raw material.Coke oven gas,discharged from coke oven chamber,cannot be used directly for containing impurities such as tar.The tar content is 80-120 g/m3,accounting for about 30%of the total quality of gas.Tar is easily to aggregate and coke under 500?,and this will cause the clogging in pipeline,equipment corrosion and environment pollution.In order to ensure production safety,meet the clean production standard and improve the quality of coke oven gas,coke oven gas needs to be purified and treated before used or further processed.Currently,the commonly method used to remove tar is the physical method,which wastes the obvious heat of tar and this method is expensive.In recent years,the researchers have carried out the study of the chemical method to remove tar.This method aims to transform tar into small molecular combustible components.By this way,not only can effectively remove tar,but also can converte tar into clean gas-H2.H2 can be directly used for blast furnace ironmaking,and this can realize the rapid reduction of iron.The catalytic reforming method of the tar is a more economical and more efficient method for the removal of tar.The preparation of the highly effective and stable catalyst is the core of this method.Nickel-base catalyst is an efficient and stable catalyst,and the catalytic reforming of CO2 adsorption can improve the yield of hydrogen.On the basis of previous study,the preparation of coupling of coke oven waste gas reforming with CO2 adsorption of catalyst are commented in this paper.The catalyst has both catalytic effect and CO2 adsorptionat due to CO2 adsorbent.In this paper,the specific study contents include:Firstly,using three different preparation methods(coprecipitation method,high temperature calcination method,sol-gel and impregnation method),five kinds of calcining temperature(800?,900?,1000?,1100?,1200?),three kinds of calcination time(2h,4h,6h),five kinds of load ratio(CaO:C12A7::NiO=70:10:20,70:20:10,70:15:15,30:55:15,50:35:15)33 kinds of catalyst were prepared.And their physical performance was tested by SEM and XRD;Secondly,the catalysts were tested for adsorption performance,and the catalyst with optimum adsorption performance was selected;Thirdly,the catalytic reforming experiment was conducted to optimize the catalytic performance,and the effect of reaction conditions on the catalytic performance was investigated.The conclusions are as follows:(1)By SEM and XRD,the physical properties of the catalysts were characterized and tested The results showed that under the calcination temperature 1000? calcination time 4h,CaO:C12A7:NiO=70:15:15,the structure is less loose,and there are more pore and better phase composition;Prepared by high temperature roasting-immersion method,under calcination temperature 1000?,calcination time 4h,CaO:C12A7:NiO=70:15:15,there are more pore and better phase composition and better phase composition;the structure of the catalyst prepared by sol-gel is relatively tight and the pores are very few.(2)The adsorption performance was tested.And the influence of calcining temperature,calcining time,the influence of the preparation method of coupling catalyst adsorption performance was tested.The results showed that using coprecipitation method,under the calcination temperature 1000?,calcining time 4h under the optimal coupling of the preparation of the catalyst adsorption performance,after the adsorption mass fraction was 151.7%.(3)The catalytic reforming experiment was carried out,to inspect the load ratio on the catalytic performance of catalyst for coupling effect and the influence of reaction conditions on the catalytic reforming reaction.The results showed that when CaO:C12A7:NiO=70:15:15,the optimal coupling performance of catalyst,hydrogen can be in 100%concentration lasts for about 18 minutes,hydrogen production rate could reach 85%;When the reaction temperature is 750?,and S/C=12,the catalytic reforming reaction was the most efficient,the hydrogen could be maintained at 100%concentration for about 18 minutes,and the yield of hydrogen could reach 86%. |
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