Direct Coal Liquefaction with Fe3O4 Nanocatalysts Prepared by a Simple Solid-State Method

Abstract

Fe 3 O 4 nanoparticles were prepared by a simple solid-state method under ambient conditions. The obtained nanoparticles, with small size and large surface area, were used as a catalyst for direct coal liquefaction (DCL). The results display that high conversion and oil yield were achieved with the nanocatalysts in direct liquefaction of two kinds of coals, i.e., Heishan coal and Dahuangshan coal. The effects of the temperature, initial H 2 pressure, and holding time on conversion and product distribution have been investigated in the catalytic hydrogenation of Dahuangshan coal. The optimal reaction condition for DCL in which conversion and oil yield are 96.6 and 60.4 wt % was determined with Fe 3 O 4 nanocatalysts. This facile solid-state route is beneficial for scale-up synthesis of iron-based catalysts with good performance for DCL.

Fe3O4 Nanoparticles Supported on Modified Coal toward Catalytic Hydrogenation of Coal to Oil

“…The process of DCL catalyzed by Fe 3 O 4 /Coal-HCl and the separation procedure of products were similar to the previous studies. 35 − 37 In a typical experiment, 10.0 g of the Dahuangshan coal, 20.0 g of tetralin as a solvent, 0.379 g of Fe 3 O 4 /Coal-HCl (Fe is 1.4 wt % of dry and ash-free (daf) coal) as a catalyst, and 0.118 g of sulfur (S/Fe mole ratio is 1.8) as a cocatalyst were mixed and charged into the reactor. Then, the autoclave was pressurized with H 2 (99.99%) to 6 MPa at room temperature and heated to 430 °C.…”

Room-Temperature Solid-State Preparation of CoFe2O4@Coal Composites and Their Catalytic Performance in Direct Coal Liquefaction

“…The process of DCL catalyzed by obtained catalysts and the separation procedure of products were similar to the previous studies. [18,21,31] In a typical experiment, 7.0 g of coal, 14.0 g of tetralin as a solvent, CoFe 2 O 4 @Coal (Fe is 1.4 wt % of dry and ash-free (daf) coal) as a catalyst, and sulfur (S/Fe mole ratio is 1.8) as a cocatalyst were mixed and charged into the reactor.…”

“…In recent years, the research on liquefaction has mainly focused on the production of organic materials from coal [14], optimizing the hydrogen donor solvent [15], understanding the liquefaction mechanism [16,17], as well as designing catalyst with excellent performance, which can efficiently facilitate the coal liquefaction and promote the coal cracking. Many efforts have been devoted to improving its catalytic activities toward hydropyrolysis of coal, such as constructing composite [1], reducing size [18,19], and improving the dispersity of catalysts [20]. Small-sized Fe 3 O 4 nanoparticles exhibited high coal conversion and oil yield as catalysts for DLC [18].…”

“…Many efforts have been devoted to improving its catalytic activities toward hydropyrolysis of coal, such as constructing composite [1], reducing size [18,19], and improving the dispersity of catalysts [20]. Small-sized Fe 3 O 4 nanoparticles exhibited high coal conversion and oil yield as catalysts for DLC [18]. The oleic acid-coated Fe 3 O 4 and Fe 2 O 3 nanoparticles have presented a superior performance in catalytic DCL [21,22].…”

Synthesis of an innovative SF/NZVI catalyst and investigation of its effectiveness on bio-oil production in liquefaction process alongside other parameters

“…Among these catalysts, nanosized iron-based materials are common due to their superior catalytic activity and low cost. In a study conducted with the Fe 3 O 4 nanocatalyst, the total conversion and oil yield of coal were obtained as 96.6% and 60.4%, respectively, under optimal reaction conditions (Li et al 2017 ). The total conversion, oil yield, and liquefaction degree of local coal with another iron-based nanocatalyst coated with oleic acid were found to be 97.2%, 86.5%, and 92.0%, respectively.…”