Effect of Pretreatment with Sulfuric Acid on Catalytic Hydrocracking of Fe/AC Catalysts

Ruiyu Wang,Ling Liu,Fei Wang

doi:10.1155/2017/9860619

Ruiyu Wang, Ling Liu + Show 1 more

Open Access

https://doi.org/10.1155/2017/9860619

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Abstract

Activated carbon (AC) was modified by H2SO4 and used as a support for catalyst. The Fe2S3/AC-T catalyst was prepared by deposition-precipitation method and used to catalyze hydrocracking of coal-related model compound, di(1-naphthyl)methane (DNM). The properties of catalyst were studied by N2 adsorption-desorption, X-ray diffraction, and scanning electron microscopy. The result showed that ferric sulfate and acidic centers had synergetic effect on hydrocracking of DNM when using Fe2S3/AC-T as catalyst, the optimal loading of Fe is 9 wt.%. Hydroconversion of the extraction residue from Guizhou bituminous coal was also studied using Fe2S3/AC-T as the catalyst. The reaction was conducted in cyclohexane under 0.8 Mpa of initial hydrogen pressure at 310°C. The reaction mixture was extracted with petroleum ether and analyzed by GC/MS. Amounts of organic compounds which fall into the categories of homologues of benzene and naphthalene were detected. It suggested that the catalyst could effectively catalyze the cleavage of C-C-bridged bonds.

Highlights

As an important chemical process, direct coal liquefaction (DCL) could be a feasible option to directly convert coals into liquid fuels or chemicals [1, 2]
At 270°C, the conversion rate of DNM over Fe2S3/activated carbon (AC)-T with various Fe loading was below 1%
The results indicated that 9% of Fe loading is appropriate for the catalyst and excessive ferric sulfide may result in a decrease of specific surface area, which in turn reduce the catalytic efficiency

Summary

Introduction

As an important chemical process, direct coal liquefaction (DCL) could be a feasible option to directly convert coals into liquid fuels or chemicals [1, 2]. Considerable efforts [8–15] have been contributed to the catalytic performances of metal-based (Fe and Ni) catalysts for DCL or to the reactions of coal-related model compounds. The cleavage of C-C bridged bonds in coals, which is very important for DCL, begins with the secondary distribution of AHAs in the whole reaction system [9, 15, 17]. Iron sulfides are commonly used catalyst for DCL because of their easy availability. The iron-based catalysts are successfully used in industrial processes of DCL, their efficiency is still quite low. Solid acids are commonly catalyst for cracking reactions, and the corresponding acidic sites are active for the cleavage of C-C-bridged bonds [12–14, 20, 21]. If combined with acidic centers, the Fe-based catalyst could exhibit an improved catalytic performance in DCL process. We prepared an iron sulfide-supported catalyst, the activated carbon (AC) which was modified by H2SO4 was used as support, and the catalysts were used to catalyze hydrocracking of a coal-related model compound (DNM) and hydroconversion of the extraction residue of a bituminous coal

Experiments

Results and Discussion

Conclusions