Investigation On Activated Carbon Supported Cobalt Catalysts For Fischer-Tropsch Synthesis

The synthesis of liquid fuel based on Fischer-Tropsch (F-T) synthesisthrough the coal or natural gas would have significant meaning in resolving theproblems of the national energy-supply security and environment protection inChina. To develop one kind of catalyst, which has good character in liquid fuelsynthesis and simplify the industrial craft or manipulation, would low down theinvestment in naphtha and diesel oil distillates synthesis. It would promote thedevelopment of liquid fuel synthesis based on F-T synthesis.This paper studied the character of Co/AC catalysts in the synthesis ofnaphtha and diesel oil distillates through F-T synthesis. The catalysts displayedhigh activity and selectivity of naphtha and diesel oil distillates, there is littlelong-chain hydrocarbon in the product, the selectivity of C₅⁺ in product could beup to 80.0 %.The occurrence of Co₂C species in Co/AC catalysts, which was formedthrough the chemical interaction between the activated carbon and Co, wasfounded by the XRD and XPS characterization for the catalysts before and afteractivation. The presentation of Co₂C would low down the activity of catalystsand influence the selectivity of catalysts according to the reaction data. Manydifferent methods had been developed successfully to restrain the formation ofCo₂C, by which the activity of catalysts would increase.XRD, TPR, CO-TPD, EDS, TEM and SEM were used to characterize theeffects of Ti, La, Cr and Mn on the performance of Co/AC catalysts. Theaddition of Mn, La could change the activity of Co/AC catalyst and theselectivity of products, and change the ability of Co2C formation in catalysts;The addition of Ti,Cr could all restrain the formation of Co2C, which wouldinduce the activity increase for Co/AC catalysts. This paper also presented the works of my master procedure, during whichthe evidence for the atom of N incorporating into the framework of SAPO-11molecular sieves had been obtained by the characterizations of XRD, BET, Al 27and P MAS NMR, the basic nitrogen-incorporated SAPO-11 molecular sieves 31had been synthesized by secondly-synthesis successfully.