The use of sulfur to extract hydrogen from coal

An Industrial-Based Consortium to Develop Premium Carbon Products from Coal Final Report - Part 2

“…The results obtained in these latter experiments demonstrate that the extent of dehydrogenation by sulfur at 500°C appears comparable to that obtained in the absence of sulfur, only at much higher temperatures. This is broadly consistent with the findings of Jusino and Schobert (2006) who produced a product much like metallurgical coke but at much lower temperatures than in a conventional coke oven. Flow-reactor tests at 700°C also produced coke cenospheres, which may have interesting potential applications.…”

“…For the continuous flow studies, a reactor similar to that described by Jusino and Schobert (2006) was built and is shown in figure 1. In the continuous flow experiments, the Pyrex glass tube (about 1 m long, 5 cm diameter) was heated in an electric furnace.…”

“…We suggest that even at this estimated price, the process would be economically attractive if high-value carbon products were being obtained at the same time. Jusino and Schobert (2006) reported preliminary work on this process. Using a mediumvolatile bituminous coal from Virginia, 70-75% of the hydrogen in the coal could be removed as H 2 S, with 97% conversions of S to H 2 S. The carbonaceous solid remaining had volatile matter, fixed carbon, ash, and friability comparable to standard samples of metallurgical coke, even though it was produced at temperatures of only 700-800°C (vs. 950-1050°C in slot-type coke ovens).…”

Sulfur as an important co-factor in the formation of multilayer graphene in the thermolyzed asphalt reaction

“…24,25,53 The faster initial loss of mass in the cyclohexanol/sulfur mixture, as opposed to the cyclohexanol-only control, can be attributed to the formation of the more volatile cyclohexene (boiling point 83 C). Past 240 C, a sequence of dehydrogenation steps continue up to 400 C. 26,27 At that temperature the 1450 cm À1 intermediate forms, where subsequent dehydrogenation produces H 2 S and multilayer graphene. Note, the mass loss is nearly complete as this is a low yield reaction.…”

“…24,25 Elemental sulfur has also been implicated in the dehydrogenation and dehydration of organics and coal. 26,27 All these processes occur at relatively low temperatures. The sum of these effects may indicate a crucial role of sulfur in the UITAR process.…”