Comparative evaluation for catalytic gasification of petroleum coke and asphaltene in subcritical and supercritical water

Catalytic gasification of wheat straw in hot compressed (subcritical and supercritical) water for hydrogen production

“…The exploiting use of fossil fuels leads to greenhouse gas emissions, global warming, air pollution and other environmental issues. 1 The increasing demand for fossil fuels, especially petroleum-based fuel products in the developing countries is raising many environmental concerns posing both short-term and long-term impacts. In such a scenario, renewable energy from wind, tidal, geothermal, solar, and biomass has many promising applications to sustain the future energy sector.…”

“…The exploiting use of fossil fuels leads to greenhouse gas emissions, global warming, air pollution and other environmental issues . The increasing demand for fossil fuels, especially petroleum‐based fuel products in the developing countries is raising many environmental concerns posing both short‐term and long‐term impacts.…”

Experimental Investigation on Supercritical Water Gasification of Organic-Rich Shale with Low Maturity for Syngas Production

“…Supercritical water gasification (SCWG) of organic feedstock is a promising technology for hydrogen-rich syngas production . Supercritical water is water above its critical points (374 °C and 22.1 MPa), and it has many distinctive physical and chemical properties, such as high density, low viscosity, low dielectric constant, and high diffusivity. − Supercritical water can provide a homogenous hydrothermal environment and enhance heat and mass transfer for organic matter conversion. − The SCWG characteristics by using biomass, − fossil fuels, − and organic wastes − as the feedstock have been investigated. Real biomass and its derived components (cellulose, glycerol, lignin, etc.)…”

“…were the most common feedstocks for hydrogen production. , The gas products were found to be H 2 , CO 2 , CH 4 , CO, and light hydrocarbons, and the typical reaction routes including hydrolysis and steam reforming were also proposed. , SCWG is also a clean and efficient method of coal conversion to produce hydrogen. − A series of studies on parameter effects, reaction mechanisms, kinetics parameters, operating conditions of complete gasification, and catalyst effects were performed. − This is a complex physicochemical process, including a heterogeneous pathway (liquefaction, extraction, pyrolysis, and hydrolysis) and a homogenous pathway (reforming, water–gas shift, and methanation) . The gas products are H 2 , CO 2 , CH 4 , and CO after almost complete gasification, and it is generally believed that these gases are mainly produced by the reactions of steam reforming, water–gas shift, and methanation in addition to pyrolysis. − Petroleum and its derivatives were also investigated as potential feedstocks of SCWG for hydrogen-rich gas production. , Isooctane and n -decane were treated as the model compounds for gasoline and diesel, respectively. Xu et al reported that the carbon gasification efficiency of diesel reached 98.12% at 23 MPa and 680 °C with addition of K 2 CO 3 when the diesel concentration in the reactor was 4.7 wt %.…”

“…41−44 Petroleum and its derivatives were also investigated as potential feedstocks of SCWG for hydrogen-rich gas production. 27,28 Isooctane and n-decane were treated as the model compounds for gasoline and diesel, respectively. Xu et al 45 reported that the carbon gasification efficiency of diesel reached 98.12% at 23 MPa and 680 °C with addition of K 2 CO 3 when the diesel concentration in the reactor was 4.7 wt %.…”