Hydrogen-donating capacity of hydrothermal system in catalytic and non-catalytic desulfurization of sulfur compound of unconventional crudes and residues: Deuterium tracing study

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-09, Vol.495, p.153626, Article 153626
• Main Authors: Zhou, Xiaodong, Al-Muntaser, Ameen A., Varfolomeev, Mikhail A., Neklyudov, Vadim, Saeed, Shadi A., Suwaid, Muneer A., Feoktistov, Dmitriy A., Mingazov, Gazinur Z., Djimasbe, Richard, Khelil, Ismail, Hosseinpour, Morteza, Rakhmatullin, Ilfat Z., Yuan, Chengdong, Hail Hakimi, Mohammed, Gareev, Bulat I., Klochkov, Vladimir V.
• Format: Article
• Language: English
• Subjects: Deuterium tracing; Hydrothermal desulfurization; Oil soluble catalyst; Sulfur Compounds; Unconventional energy resources
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.153626

[Display omitted] •Deuterium tracing techniques confirm role of water as a green hydrogen donor in HT-DS.•Nickel (II) stearate boosts HT-DS efficiency, reaching up to 97.34% conversion.•Catalytic process aids in producing desulfurized products like Bibenzyl and (E)-Stilbene.•Combines experimental and DFT for deep mechanistic insights.•GC–MS as an advanced tracing technique validates the molecular weight increase in products. This research tries to figure out the role of water as a green and environmental hydrogen-donor solvent for catalytic and non-catalytic hydrothermal desulfurization (HT-DS) of dibenzyl sulfide (DBS) as a sulfur model compound of unconventional crudes and petroleum residues using deuterium tracing techniques. In addition, the ordinary water (H2O) was replaced by heavy water (D2O) to ease the evaluation of the donating capacity of water as a hydrogen donor during HT-DS process of selected sulfur model compound. The hydrothermal conversion (HTC) of dibenzyl sulfide and donating performance of heavy water were deeply investigated through comprehensive analysis of the initial and converted obtained products encompassing gas, liquid, and solid phase (if obtained), using different techniques GC, GC–MS, FTIR, high resolution deuterium (2H) NMR, and isotope analysis. The results of the non-catalytic and catalytic HTC of DBS show high conversion degree of 75.79 and 97.34 %, respectively, resulting in the formation of desulfurized compounds consisting of bibenzyl and stilbene. Additionally, the results of the deuterium tracing study proved the role of water as a green and environmental hydrogen-donor solvent during HT-DS of DBS, verified by considerable deuterium substitution (H/D exchanges) in both liquid (converted) and gases products. The results of the GC–MS as a tracing technique showed by molecular weight data the formation of the individual deuterium containing products in liquid and gas phases for both catalytic and non-catalytic HT-DS. Simultaneously, both experimental and DFT results showed that the application of nickel (II) stearate as an oil-soluble catalyst promoted both HTC of DBS. The important finding about the role of water in catalytic and non-catalytic HT-DS of DBS not only enriches the theoretical basis in this area, but also provides a strong support for the combined use of water and catalysts for improving conversion and desulfurization performance, thereby offering insights into the optimization of hydrothermal processes f