Conversion of sulfur-rich asphaltite in supercritical water and effect of metal additives

A Review of Laboratory-Scale Research on Upgrading Heavy Oil in Supercritical Water

“…Accordingly, a proper O2 amount is needed to guarantee the catalytic desulfurization of VR at a minimum expense cost. Apart what is listed above, the effect of metals (Zn, Al) [41,103] and catalysts (ZnO, MoO3 and MoS2) [12] on the desulfurization of heavy oil and model compounds in SCW have also been reported. Kida et al [75] proposed the reaction mechanism of hexyl sulfide (shown in Figure 7) in SCW, based on the analysis of experimental results and theory calculation.…”

Zinc sulfidation by H2S and H2S/H2O supercritical fluids: Synthesis of nanoparticles and catalytic effect of water

“…Earlier we revealed that addition of zinc shavings to sulfur-rich asphaltite resulted in significant decrease in the amount of H 2 S in the volatile products during asphaltite pyrolysis in vacuum (T ≤ 400 • C) [15]. During conversion of bitumen [10], asphaltite [15] and coal [16] in supercritical water flow (400 • C, 30 MPa) the desulfurization degree (the weight portion of sulfur atoms of raw fuels passed into ZnS) of conversion products achieved 13, 60, and 42%, respectively.…”

“…Our interest in the study of zinc sulfidation is caused, first of all, by the possibility of using zinc for desulphurization and hydrogenation of low-grade fuels (oil shale [8], bitumen [9,10], oil sand bitumen [11], asphalt [12], asphaltite [13][14][15], and coal [16]) during their conversion in supercritical water (T cr = 374 • C, P cr = 22.1 MPa [17]). When zinc is added, hydrogenation of fuels is possible owing to hydrogen evolution during zinc oxidation by supercritical water [10,15,16].…”

“…When zinc is added, hydrogenation of fuels is possible owing to hydrogen evolution during zinc oxidation by supercritical water [10,15,16]. The kinetics and mechanisms of oxidation of the bulk zinc samples by water vapor and supercritical water were earlier studied by us [18,19]; the oxidation occurred via ZnO nanoparticles formation in terms of the following reaction:…”

“…During conversion of bitumen [10], asphaltite [15] and coal [16] in supercritical water flow (400 • C, 30 MPa) the desulfurization degree (the weight portion of sulfur atoms of raw fuels passed into ZnS) of conversion products achieved 13, 60, and 42%, respectively. The desulfurization of conversion products in [10,15,16] is caused by the interaction of H 2 S with zinc and zinc oxide formed by the reaction (1) in situ as a result of the following reactions:…”