Optimizing Process For Preparation Of Activated Carbon From Petroleum Coke And Characterization Of Its Porosity

Petroleum coke is one byproduct in the process of oil refining. At present, it is mainly used in metallurgy refining. Unfortunately, the high sulfur content of raw oil hamper the use of coke in metallurgy industry. So new application field need to found for that petroleum coke with high sulfur content. Due to having high carbon content and low ash content, petroleum coke has been regarded as a good raw material to prepare activated carbon. And the sulfur favor forming porosity in preparation of activated carbon.Activated carbon, which has high specific surface area and lots of pores with different size, was widely used as adsorbent in many fields, which include environment protection, chemical and chemistry industry, oil industry, metallurgy, drug refining and military protection, etc. In this paper, DuShanzi petroleum coke was used as raw material and ZnCl2 as active agent to prepare activated carbon. Two heating methods including electricity and microwave were employed. The adsorption ability of prepared activated carbon was characterized by adsorptions of nitrogen, iodine and benzene.For the preparation of activated carbon heated by electricity, the kind and content of active agent, mix mode, temperature and time of activation, and carbonized temperature were investigated. In the studied range, the optimum conditions are as follows. Weight ratios of ZnCl2, petroleum coke and coal tar pith are 2, 7 and 1, respectively, mix mode is extrusion in normal temperature, carbonized temperature is 500℃and holding for 1 hour, activation temperature is 800℃and keeping for 6 hours. The specific surface area is 798.5㎡/g, the iodine capacity is 745.8mg/g, and the adsorbed benzene is 531.1mg/g. The strength of prepared activated carbon is 61.2N.For the preparation of activated carbon heated by microwave, the optimum conditions are as follows. Weight ratios of ZnCl2, petroleum coke and coal tar pith are 1.5, 7.5 and 1,respectively. The power of microwave is 1300W and the irradiation time is 6 minutes. The specific surface area of prepared activated carbon is 1095.7㎡/g, the iodine capacity is 673.7mg/g, and the benzene capacity is 781.1mg/g. The strength of prepared activated carbon is 20.3N.Micropore was charactered,as well as mesopore,pore's shape,surface's figure,surface's property and surface's area, showing that the activated carbon's porosity made by microwave is different from that of activated carbon prepared by electricity.The specific surface area and adsorption ability of activated carbon made by microwave are higher those of actived carbon prepared by electricity.