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The study aims at coal desulphurization prior to its combustion to reduce the environmental hazards. The process of desulphurization was performed by using microwave-assisted technology in alkaline medium. Response surface methodology (RSM) was employed for the optimization of the removal of sulfur from coal samples by microwave treatment in order to study the interactive and simple effects of operational variables. The parameters, that is, coal particle size, power of microwave, and time of irradiation, were examined. Precipitation method with barium chloride was used for the estimation of sulfur removal. Samples of coal were ground into different particle sizes and then slurries of coal were made in aqueous media and finally irradiated with microwaves in the presence of KOH medium. The measured response was sulfur reduction up to 60%. Time of irradiation and power of microwave have significant effect on desulphurization of coal. [ABSTRACT FROM AUTHOR]

Combustion of coal produces oxides of sulfur that is harmful for the environment. Present research work was aimed to appraise the desulfurization of coal using high-energy radiations. Gamma radiations (γ-rays) and ultraviolet radiations (UV) were employed for the desulfurization of coal under different media conditions. Coal slurries in these media were treated for different time intervals of UV radiation and γ-rays doses (50, 100, 150 kGy). The maximum sulfur removal was achieved up to 54 and 36% by γ-radiation and UV radiation, respectively, which is due to the more ionizing power of γ-rays treatment. To effectively and efficiently remove sulfur from coal, the use of high-energy radiations is suggested for the desulfurization of coal. [ABSTRACT FROM AUTHOR]

The mechanism of coal desulfurization by photo-catalytic oxidation treatment is expatiated. This work describes the desulfurization of coal by photocatalysis oxidation treatment; slurries of coal in aqueous media were mixed with H2O2,nano-catalyst (ZnO) and irradiated with a UV radiation source. Sulfur removal was estimated by the barium precipitation method. The interactive effects of operational parameters such as coal particle size, catalyst concentration, time of irradiation, and concentration of hydrogen peroxide were also investigated. The interactive and simple linear effect of each operational parameter was analyzed by using the response surface methodology (RSM) with central composite rotatable design (CCRD). The results demonstrated that particle size had a weak correlation with the magnitude of desulfurization while positive impact has been generated by hydrogen peroxide. [ABSTRACT FROM AUTHOR]

This study includes geochemical characterization of source rock samples from the Upper shale, Lower shale, Talhar shale units of Sembar Formation and Badin shale, Turk shale units of Lower Goru Formation. Fourteen (14) sediment samples have been obtained from various wells located in Badin area of Lower Indus Basin and were analyzed to evaluate thermal history, depositional settings and generative potential. The bitumens obtained by soxhlet extraction were fractionated into saturates, aromatics, NSOs and asphaltenes/resins by column chromatography on silica gel. Saturated fractions isolated by column chromatography were analyzed by Gas Chromatography-Flame Ionization Detector. TOC determined by wet combustion titration method revealed fair to good source rock potential. Pr/Ph ratios and hydrocarbons distributions show anoxic to oxic depositional environment. The TAR ratio,nC31/nC19ratio, and odd carbon number predominance suggest land plant organic matter input. The values of CPI, OEP and Bit/TOC suggest that these Cretaceous sequences of Sembar and Lower Goru formation are of intermediate maturity and lie within the onset of oil genesis zone. [ABSTRACT FROM PUBLISHER]

In previous studies, Patala-Nammal Composite Total Petroleum System (TPS) was recognized as a potential source of hydrocarbon in the Upper Indus Basin, and Sembar-Goru Composite TPS in the Lower Indus Basin. However, petroleum source-rock potential of Cretaceous strata in the Indus Basin is poorly known. In the current study, Rock Eval and total organic carbon (TOC) analyses were conducted to investigate the thermal maturity and source-rock potential of Cretaceous unit in the Lower Indus Basin. The Parh Formation of the Lower Indus Basin is lean in organic contents (TOC < 0.73%) and consistent with immature type-III/IV kerogen. The Upper Goru Formation is fair in organic contents and presents similar characteristics to the Parh Formation with respect to the hydrocarbon generation zone. The Lower Goru Formation presents fair to very good organic contents. The members of Lower Goru Formation have enough organic matter (OM) and are mature, with the exception of Badin shales. The OM, throughout the formation, is predominantly gas prone. The Sembar Formation is fair in organic contents and mature with respect to hydrocarbons generation. These results support that the Lower Goru rocks are comparatively more prospective with respect to hydrocarbons. [ABSTRACT FROM AUTHOR]

Geochemical analyses of the 10 crude oils from Cretaceous sequences, Lower Indus Basin, Pakistan, are performed to characterize source, depositional environment, biodegradation, and thermal maturity to establish genetic relationship. Low sulfur, high pristane/phytane (Pr/Ph) ratios, and high American Petroleum Institute gravity indicate oxic depositional environment and terreginous input of organic matter (OM). Full suite ofn-alkanes, low isoprenoid/n-alkane ratios, elevated saturates/aromatics ratios, and the absence of unresolved complex mixture indicate typical non-biodegraded light crude oils. The carbon preference index, odd even predominance, Pr/n-C17, and Ph/n-C18ratios reveal that source rocks generating Lower Indus Basin crude oils are thermally mature. Based on geochemical analyses, the source OM input is probably terreginous mixed with marine, deposited under suboxic to oxic depositional environments. [ABSTRACT FROM PUBLISHER]