Browsing Faculty of Engineering by Author "Neomagus, Hein W.J.P."
Now showing items 1-20 of 42
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The adsorption of copper in a packed-bed of chitosan beads: Modeling, multiple adsorption and regeneration
Osifo, Peter O.; Neomagus, Hein W.J.P.; Everson, Raymond C.; Webster, Athena; Gun, Marius A. (Elsevier, 2009)In this study, exoskeletons of Cape rock lobsters were used as raw material in the preparation of chitin that was successively deacetylated to chitosan flakes. The chitosan flakes were modified into chitosan beads and the ... -
Assessing the catalytic effect of coal ash constituents on the CO2 gasification rate of high ash, South African coal
Hattingh, Burgert B.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bunt, John R. (Elsevier, 2011)The catalytic effect of inorganic species, within the ash, on the CO2 gasification of three South African coals containing similar carbon-structural properties (elemental, structural and petrographical properties) was ... -
The carbon dioxide gasification characteristics of biomass char samples and their effect on coal gasification reactivity during co-gasification
Mafu, Lihle D.; Neomagus, Hein W.J.P.; Everson, Raymond C.; Strydom, Christien A.; Bunt, John R. (Elsevier, 2018)The carbon dioxide gasification characteristics of three biomass char samples and bituminous coal char were investigated in a thermogravimetric analyser in the temperature range of 850–950 °C. Char SB exhibited higher ... -
The carbon dioxide, methane and nitrogen high-pressure sorption properties of South African bituminous coals
Okolo, Gregory N.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bunt, John R.; Sakurovs, Richard (Elsevier, 2019)In this paper, we report the CO2, CH4 and N2 sorption isotherms of four dry South African bituminous coals at pressures up to 16 MPa at 55 °C. The sorption capacities of the samples with respect to the adsorbate gases ... -
The characterisation of slow-heated inertinite- and vitrinite-rich coals from the South African coalfields
Roberts, Mokone J.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Okolo, Gregory N.; Van Niekerk, Daniel (Elsevier, 2015)The development of coal char structures with pyrolysis has been extensively investigated but has traditionally been focused on the carboniferous coals in the northern Hemisphere. In this investigation, the properties of ... -
Chemical and structural characterization of char development during lignocellulosic biomass pyrolysis
Mafu, Lihle D.; Neomagus, Hein W.J.P.; Everson, Raymond C.; Strydom, Christien A.; Okolo, Gregory N.; Bunt, John R. (Elsevier, 2017)The chemical and structural changes of three lignocellulosic biomass samples during pyrolysis were investigated using both conventional and advanced characterization techniques. The use of ATR-FTIR as a characterization ... -
Chemical–structural properties of South African bituminous coals: insights from wide angle XRD–carbon fraction analysis, ATR–FTIR, solid state 13C NMR, and HRTEM techniques
Okolo, Gregory N.; Neomagus, Hein W.J.P.; Everson, Raymond C.; Roberts, Mokone J.; Bunt, John R. (Elsevier, 2015)The chemical–structural properties of four South African bituminous coals were investigated using wide angle X-ray diffraction–carbon fraction analysis (WAXRD–CFA), attenuated total reflection Fourier transform infra-red ... -
Coal-derived low smoke fuel assessment through coal stove combustion testing
Kühn, Thys; Bunt, John R.; Neomagus, Hein W.J.P.; Piketh, Stuart J.; Everson, Raymond C.; Coetzee, Sansha (Elsevier, 2017)A study was undertaken to investigate the production of low smoke fuel from coal currently used in low-income households in South Africa. Pyrolysis of large coal lumps was studied as a possible production method, and an ... -
Comparing the porosity and surface areas of coal as measured by gas adsorption, mercury intrusion and SAXS techniques
Okolo, Gregory N.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Roberts, Mokone J.; Sakurovs, Richard (Elsevier, 2015)In this paper, we compare the surface area, porosity and other physical–structural properties of four bituminous coals from three different coal fields of South Africa determined using carbon dioxide (CO2) and nitrogen ... -
Dataset on the carbon dioxide, methane and nitrogen high-pressure sorption properties of South African bituminous coals
Okolo, Gregory N.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bunt, John R.; Sakurovs, Richard (Elsevier, 2019)The dataset presented in this article supplements the result and information published in the report “The carbon dioxide, methane and nitrogen high-pressure sorption properties of South African bituminous coals” (Okolo et ... -
Density functional theory molecular modelling and experimental particle kinetics for CO2-char gasification
Roberts, Mokone J.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Van Sittert, Cornelia G.C.E.; Okolo, Gregory N. (Elsevier, 2015)Experimental measurements and DFT atomistic modelling were conducted to elucidate the mechanisms for gasification chemistry of char with CO2 gas. The molecular models used were based on experimental representations of coal ... -
Detailed characterization of SA high mineral matter inertinite–rich coals and density fractions and effect on reaction rates with carbon dioxide: macerals, microlithotypes, carbominerites and minerals
Everson, Raymond C.; Koekemoer, Andrei; Bunt, John R.; Neomagus, Hein W.J.P.; Schwarz, Christopher (SAIChE, 2013)An investigation was undertaken to determine the distribution of macerals and minerals in South African Highveld coal deposits as well as density fractions derived from a typical deposit. The corresponding effects on ... -
The effect of acid demineralising bituminous coals and de-ashing the respective chars on nitrogen functional forms
Phiri, Zebron; Everson, Raymond C.; Neomagus, Hein W.J.P.; Wood, Barry J. (Elsevier, 2017)An opportunity presented itself to compare changes in nitrogen functional forms brought by the acid treatment of South African bituminous coals and their respective chars. X-ray photoelectron spectroscopy (XPS) was used ... -
The effect of carbon dioxide partial pressure on the gasification rate and pore development of Highveld coal chars at elevated pressures
Gouws, Saartjie M.; Neomagus, Hein W.J.P.; Bunt, John R.; Everson, Ray C.; Roberts, Daniel G. (Elsevier, 2018)Char structural changes occurring during gasification are normally only related to conversion and few data is published on the effect of carbon dioxide partial pressure on the extent of pore development. In this study, the ... -
Elucidation of the structural and molecular properties of typical South African coals
Hattingh, Burgert B.; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bunt, John R.; Van Niekerk, Daniel; Jordaan, Johan H.L.; Mathews, Jonathan P. (ACS, 2013)Advanced analytical techniques were performed on four South African coals, three noncoking and one coking, containing different maceral contributions (vitrinite contents ranging between 24 and 66 vol %, m.m.f.b.). ... -
Evaluating the performance and emission reductions of a coal-derived low-smoke fuel in a conventional household stove
Sumbane, Lungile P.; Piketh, Stuart J.; Bunt, John R.; Neomagus, Hein W.J.P. (IEEE, 2017)A low-smoke fuel (LSF) produced via the devolatilisation of coal lumps is proposed as an option to combat the health-damaging effects of domestic coal combustion. This study investigates the effect of the LSF particle size ... -
Experimental performance evaluation of an ammonia-fuelled microchannel reformer for hydrogen generation
Chiuta, Steven; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bessarabov, Dmitri G. (Elsevier, 2014)Microchannel reactors appear attractive as integral parts of fuel processors to generate hydrogen (H2) for portable and distributed fuel cell applications. The work described in this paper evaluates, characterizes, and ... -
Experimentation and CFD modelling of a microchannel reactor for carbon dioxide methanation
Engelbrecht, Nicolaas; Chiuta, Steven; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bessarabov, Dmitri G. (Elsevier, 2017)The methanation of carbon dioxide (CO2) via the Sabatier process is increasingly gaining interest for power-to-gas application. In this investigation, a microchannel reactor was evaluated for CO2 methanation at different ... -
Hydrogen production from ammonia decomposition over a commercial Ru/Al2O3 catalyst in a microchannel reactor: experimental validation and CFD simulation
Chiuta, Steven; Everson, Raymond C.; Neomagus, Hein W.J.P.; Bessarabov, Dmitri G. (Elsevier, 2016)In this work, an integrated experimental and CFD modelling technique was used to evaluate a microchannel reactor producing hydrogen from ammonia decomposition using a commercial Ru/Al2O3 catalyst. The microchannel reactor ... -
Improved reactivity of large coal particles by K2CO3 addition during steam gasification
Coetzee, Sansha; Neomagus, Hein W.J.P.; Bunt, John R.; Everson, Raymond C. (Elsevier, 2013)In this study, the excess solution impregnation method was used to impregnate large coal particles (5 and 10 mm) with K2CO3, and the effect of the additive on steam gasification reactivity was investigated. A washed bituminous, ...