All Outputs (14)

Geochemical evaluation and hydrocarbon generation potential of the Upper Cretaceous–Pliocene succession, offshore Nile Delta, Egypt (2023)
Journal Article
Farouk, S., Khairy, A., Shehata, A. M., Uguna, C. N., El Sheennawy, T., Salama, A., …Meredith, W. (2023). Geochemical evaluation and hydrocarbon generation potential of the Upper Cretaceous–Pliocene succession, offshore Nile Delta, Egypt. Journal of African Earth Sciences, 205, Article 105004. https://doi.org/10.1016/j.jafrearsci.2023.105004

The offshore Nile Delta is a prominent petroleum province; nevertheless, previous research focused mainly on evaluation of Miocene–Pliocene possible source rocks because of lack of data. The current study is the first to evaluate organic geochemical... Read More about Geochemical evaluation and hydrocarbon generation potential of the Upper Cretaceous–Pliocene succession, offshore Nile Delta, Egypt.

Geochemical assessment and hydrocarbon potential of Oligocene–Pliocene source rocks from northeast onshore Nile Delta, Egypt (2023)
Journal Article
Khairy, A., El Diasty, W. S., Uguna, C. N., Peters, K. E., Vane, C. H., Snape, C. E., & Meredith, W. (2023). Geochemical assessment and hydrocarbon potential of Oligocene–Pliocene source rocks from northeast onshore Nile Delta, Egypt. International Journal of Coal Geology, 274, Article 104283. https://doi.org/10.1016/j.coal.2023.104283

Recent exploration in the Nile Delta Basin has led to major oil and gas discoveries; however, source–reservoir relationships in the onshore part of the basin are still ambiguous. This work involves a comprehensive geochemical assessment of possible O... Read More about Geochemical assessment and hydrocarbon potential of Oligocene–Pliocene source rocks from northeast onshore Nile Delta, Egypt.

Should IQOS Emissions Be Considered as Smoke and Harmful to Health? A Review of the Chemical Evidence (2022)
Journal Article
Uguna, C. N., & Snape, C. E. (2022). Should IQOS Emissions Be Considered as Smoke and Harmful to Health? A Review of the Chemical Evidence. ACS Omega, 7(26), 22111–22124. https://doi.org/10.1021/acsomega.2c01527

The chemical evidence that IQOS emissions fit the definition of both an aerosol and smoke, and that IQOS and potentially other heated tobacco products (HTPs) pose some harmful health threats from the range of compounds released even at somewhat lower... Read More about Should IQOS Emissions Be Considered as Smoke and Harmful to Health? A Review of the Chemical Evidence.

Effect of process variables on producing biocoals by hydrothermal carbonisation of pine Kraft lignin at low temperatures (2022)
Journal Article
Musa, U., Castro-Díaz, M., Uguna, C. N., & Snape, C. E. (2022). Effect of process variables on producing biocoals by hydrothermal carbonisation of pine Kraft lignin at low temperatures. Fuel, 325, Article 124784. https://doi.org/10.1016/j.fuel.2022.124784

Lignin from pulping is recovered in a wet form, making it ideal for hydrothermal carbonisation (HTC). This study investigates the effects of temperature (200–280 °C), residence time (1–6 h), and water to biomass mass ratio (2:1–6:1) on the compositio... Read More about Effect of process variables on producing biocoals by hydrothermal carbonisation of pine Kraft lignin at low temperatures.

Renewable binders from waste biomass for road construction: A review on thermochemical conversion technologies and current developments (2022)
Journal Article
Weir, A., Jiménez del Barco Carrión, A., Queffélec, C., Bujoli, B., Chailleux, E., Uguna, C., …Airey, G. (2022). Renewable binders from waste biomass for road construction: A review on thermochemical conversion technologies and current developments. Construction and Building Materials, 330, Article 127076. https://doi.org/10.1016/j.conbuildmat.2022.127076

Biobinders (binders manufactured from biomass) are becoming popular in asphalt engineering due to growing environmental concerns of greenhouse gas emissions from the use of fossil fuels and depleting petroleum bitumen reserves. Waste biomass products... Read More about Renewable binders from waste biomass for road construction: A review on thermochemical conversion technologies and current developments.

Comparison of the impact of moisture on methane adsorption and nanoporosity for over mature shales and their kerogens (2021)
Journal Article
Li, W., Stevens, L. A., Uguna, C. N., Vane, C. H., Meredith, W., Tang, L., …Snape, C. E. (2021). Comparison of the impact of moisture on methane adsorption and nanoporosity for over mature shales and their kerogens. International Journal of Coal Geology, 237, Article 103705. https://doi.org/10.1016/j.coal.2021.103705

© 2021 Elsevier B.V. Moisture in shales under reservoir conditions adversely affects gas adsorption and nanoporosity and is also likely to impact on the contribution that kerogen makes to the methane adsorption capacity. To investigate these phenomen... Read More about Comparison of the impact of moisture on methane adsorption and nanoporosity for over mature shales and their kerogens.

Pore structural evolution of shale following thermochemical treatment (2019)
Journal Article
Rigby, S. P., Jahan, H., Stevens, L., Uguna, C., Snape, C., Macnaughton, B., …Fletcher, R. S. (2020). Pore structural evolution of shale following thermochemical treatment. Marine and Petroleum Geology, 112, Article 104058. https://doi.org/10.1016/j.marpetgeo.2019.104058

Shales experience heat treatment concurrent with the presence of water or steam during reservoir engineering interventions, such as high pressure water fracking and in-situ combustion of hydrocarbons. This work utilises a novel technique, which is a... Read More about Pore structural evolution of shale following thermochemical treatment.

Shale gas reserve evaluation by laboratory pyrolysis and gas holding capacity consistent with field data (2019)
Journal Article
Whitelaw, P., Uguna, C. N., Stevens, L. A., Meredith, W., Snape, C. E., Vane, C. H., …Carr, A. D. (2019). Shale gas reserve evaluation by laboratory pyrolysis and gas holding capacity consistent with field data. Nature Communications, 10(1), Article 3659. https://doi.org/10.1038/s41467-019-11653-4

Exploration for shale gas occurs in onshore basins, with two approaches used to predict the maximum gas in place (GIP) in the absence of production data. The first estimates adsorbed plus free gas held within pore space, and the second measures gas y... Read More about Shale gas reserve evaluation by laboratory pyrolysis and gas holding capacity consistent with field data.

Evaluation of hydrochars from lignin hydrous pyrolysis to produce biocokes after carbonization (2016)
Journal Article
Castro-Díaz, M., Uguna, C. N., Florentino, L., Díaz-Faes, E., Stevens, L., Barriocanal, C., & Snape, C. (2017). Evaluation of hydrochars from lignin hydrous pyrolysis to produce biocokes after carbonization. Journal of Analytical and Applied Pyrolysis, 124, 742-751. https://doi.org/10.1016/j.jaap.2016.11.010

Hydrochars were obtained after hydrous pyrolysis of a pine Kraft lignin using different reaction conditions (temperature, water content and residence time) and the residues were characterized through a wide range of analytical techniques including hi... Read More about Evaluation of hydrochars from lignin hydrous pyrolysis to produce biocokes after carbonization.

Retardation of oil cracking to gas and pressure induced combination reactions to account for viscous oil in deep petroleum basins: Evidence from oil and n-hexadecane pyrolysis at water pressures up to 900bar (2016)
Journal Article
Uguna, C. N., Carr, A. D., Snape, C. E., & Meredith, W. (2016). Retardation of oil cracking to gas and pressure induced combination reactions to account for viscous oil in deep petroleum basins: Evidence from oil and n-hexadecane pyrolysis at water pressures up to 900bar. Organic Geochemistry, 97, 61-73. https://doi.org/10.1016/j.orggeochem.2016.04.007

This study reports a laboratory pyrolysis experimental study on oil and n-hexadecane to rationalise the thermal stability of oil in deep petroleum reservoirs. Using a 25 ml Hastelloy pressure vessel, a 35° API North Sea oil (Oseberg) and n-hexadecane... Read More about Retardation of oil cracking to gas and pressure induced combination reactions to account for viscous oil in deep petroleum basins: Evidence from oil and n-hexadecane pyrolysis at water pressures up to 900bar.

Thermal Cracking of Oil under Water Pressure up to 900 bar at High Thermal Maturities. 1. Gas Compositions and Carbon Isotopes (2016)
Journal Article
Xie, L., Sun, Y., Uguna, C. N., Li, Y., Snape, C. E., & Meredith, W. (2016). Thermal Cracking of Oil under Water Pressure up to 900 bar at High Thermal Maturities. 1. Gas Compositions and Carbon Isotopes. Energy and Fuels, 30(4), 2617-2627. https://doi.org/10.1021/acs.energyfuels.5b02792

In this study, a C9+ fraction of saturate-rich Tertiary source rock-derived oil from the South China Sea basin was pyrolyzed in normal and supercritical water using a 25 mL vessel at a range of temperature from 350 to 425 °C for 24 h, to probe pressu... Read More about Thermal Cracking of Oil under Water Pressure up to 900 bar at High Thermal Maturities. 1. Gas Compositions and Carbon Isotopes.

Pyrolysis oil upgrading in high conversions using sub- and supercritical water above 400 °C (2016)
Journal Article
Isa, K. M., Snape, C. E., Uguna, C., Meredith, W., & Deng, H. (2016). Pyrolysis oil upgrading in high conversions using sub- and supercritical water above 400 °C. Journal of Analytical and Applied Pyrolysis, 119, 180-188. https://doi.org/10.1016/j.jaap.2016.03.004

The upgrading of pyrolysis oil to bio-fuel was investigated using sub- and supercritical water at 410 and 450oC, with a high mass ratio of water to pyrolysis oil to ascertain the maximum yields that could be achieved. The results indicate that conver... Read More about Pyrolysis oil upgrading in high conversions using sub- and supercritical water above 400 °C.

Impact of high water pressure on oil generation and maturation in Kimmeridge Clay and Monterey source rocks: implications for petroleum retention and gas generation in shale gas systems (2016)
Journal Article
Uguna, C. N., Carr, A. D., Snape, C. E., Meredith, W., Scotchman, I. C., Murray, A., & Vane, C. H. (2016). Impact of high water pressure on oil generation and maturation in Kimmeridge Clay and Monterey source rocks: implications for petroleum retention and gas generation in shale gas systems. Marine and Petroleum Geology, 73, https://doi.org/10.1016/j.marpetgeo.2016.02.028

This study presents results for pyrolysis experiments conducted on immature Type II and IIs source rocks (Kimmeridge Clay, Dorset UK, and Monterey shale, California, USA respectively) to investigate the impact of high water pressure on source rock ma... Read More about Impact of high water pressure on oil generation and maturation in Kimmeridge Clay and Monterey source rocks: implications for petroleum retention and gas generation in shale gas systems.

High pressure water pyrolysis of coal to evaluate the role of pressure on hydrocarbon generation and source rock maturation at high maturities under geological conditions (2014)
Journal Article
Uguna, C. N., Carr, A. D., Snape, C. E., & Meredith, W. (2015). High pressure water pyrolysis of coal to evaluate the role of pressure on hydrocarbon generation and source rock maturation at high maturities under geological conditions. Organic Geochemistry, 78, 44-51. https://doi.org/10.1016/j.orggeochem.2014.10.013

© 2014 Elsevier Ltd. This study investigates the effect of water pressure on hydrocarbon generation and source rock maturation at high maturities for a perhydrous Tertiary Arctic coal, Svalbard. Using a 25. ml Hastalloy vessel, the coal was pyrolysed... Read More about High pressure water pyrolysis of coal to evaluate the role of pressure on hydrocarbon generation and source rock maturation at high maturities under geological conditions.