Search Results - "Knoetze, Johannes H"

Using Apparent Activation Energy as a Reactivity Criterion for Biomass Pyrolysis by Carrier, Marion, Auret, Lidia, Bridgwater, Anthony, Knoetze, Johannes H

“…The reactivity of chemically isolated lignocellulosic blocks, namely, α-cellulose, holocellulose, and lignin, has been rationalized on the basis of the…”
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Additional Pilot Plant Measurements with Incorporation of Reflux for the Fractionation of Wax Derivatives with Supercritical Propane by Schwarz, Cara. E, Nieuwoudt, Izak, Knoetze, Johannes. H

“…Previous studies have shown that supercritical propane can be used to fractionate waxlike alcohol ethoxylates according to the number of ethylene oxide units…”
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Thermodynamic modelling of supercritical water gasification: Investigating the effect of biomass composition to aid in the selection of appropriate feedstock material by Louw, Jeanne, Schwarz, Cara E., Knoetze, Johannes H., Burger, Andries J.

“…[Display omitted] •A thermodynamic model of a continuous SCWG experimental setup was developed.•Effect of C:H and oxygen content of biomass are shown for…”
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Concentration of Wax Derivatives with Supercritical Fluids:  1. A Feasibility Study by Schwarz, Cara E, Nieuwoudt, Izak, Knoetze, Johannes. H

“…Currently alcohol ethoxylates produced contain a wide distribution of the number of ethylene oxide units added. One possible method to reduce the wide…”
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Thermogravimetric study of the pyrolysis characteristics and kinetics of coal blends with corn and sugarcane residues by Aboyade, Akinwale O., Görgens, Johann F., Carrier, Marion, Meyer, Edson L., Knoetze, Johannes H.

“…This paper investigates the non-isothermal thermokinetics of the co-pyrolysis of sugarcane bagasse and corn residue blended with coal. The individual…”
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Physico-chemical characterization of biochars from vacuum pyrolysis of South African agricultural wastes for application as soil amendments by Uras, Ümit, Carrier, Marion, Hardie, Ailsa G., Knoetze, Johannes H.

“…► Vacuum pyrolysis contributes to the development of CO groups on biochar's surface. ► Alkaline and acidic biochars are produced from the vacuum pyrolysis of…”
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Process efficiency of biofuel production via gasification and Fischer–Tropsch synthesis by Leibbrandt, Nadia H., Aboyade, Akinwale O., Knoetze, Johannes H., Görgens, Johann F.

“…•A thermodynamic model was used to predict syngas composition from biomass feedstock.•Results were optimised and integrated with a process model for liquid…”
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Non-isothermal kinetic analysis of the devolatilization of corn cobs and sugar cane bagasse in an inert atmosphere by Aboyade, Akinwale O., Hugo, Thomas J., Carrier, Marion, Meyer, Edson L., Stahl, Ralph, Knoetze, Johannes H., Görgens, Johann F.

“…► Non-isothermal pyrolysis kinetics of two biomass residues at slow heating rates. ► Model-free approach applied to global and pseudocomponent reaction rate…”
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Model fitting kinetic analysis and characterisation of the devolatilization of coal blends with corn and sugarcane residues by Aboyade, Akinwale O., Carrier, Marion, Meyer, Edson L., Knoetze, Johannes H., Görgens, Johann F.

“…► Multi-component 1st and nth order model fitting analysis of the non-isothermal pyrolysis kinetics of coal, biomass and coal:biomass blends. ► 3-Component nth…”
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Vapor–Liquid–Liquid Equilibria Measurements for the Dehydration of Ethanol, Isopropanol, and n‑Propanol via Azeotropic Distillation Using DIPE and Isooctane as Entrainers by Pienaar, Cornelia, Schwarz, Cara E, Knoetze, Johannes H, Burger, Andries J

“…Vapor–liquid equilibrium (VLE) and vapor–liquid–liquid equilibrium (VLLE) data were measured for the ethanol/diisopropyl ether (DIPE)/water,…”
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Reaction Kinetics of CO2 with Monoethanolamine in n‑Propanol. 1. Reaction Kinetic Data and Comparison with Existing Rate Law Expressions by Du Preez, Louis J, Barnard, Jakobus P, Callanan, Linda H, Knoetze, Johannes H

“…The reaction kinetics of CO2 with monoethanolamine is of industrial significance with respect to both CO2 sequestration applications and characterizing the…”
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Lignocellulose pyrolysis with condensable volatiles quantification by thermogravimetric analysis—Thermal desorption/gas chromatography–mass spectrometry method by Nsaful, Frank, Collard, François-Xavier, Carrier, Marion, Görgens, Johann F., Knoetze, Johannes H.

“…•TGA-TD/GC–MS method developed to quantify condensable volatiles from lignocellulose pyrolysis.•Average RSD of 6.4% obtained for quantification of most…”
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The influence of liquid physical properties on entrainment inside a sieve tray column by Uys, Ehbenezer C., Burger, Andries J., Du Preez, Louis J., Knoetze, Johannes H.

“…[Display omitted] •New sieve tray L′/G data for a wider range of liquid phase physical properties.•Entrainment found to decrease for an increase in liquid…”
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Hydrodynamics of a Packed Column Operated under Supercritical Conditions by Herman Franken, H. Knoetze Johannes, Cara Schwarz

“…There is a lack of hydrodynamic data under supercritical conditions, in particular in systems that attempt to isolate hydrodynamics from mass transfer. This…”
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Influence of Chemical Pretreatment on the Internal Structure and Reactivity of Pyrolysis Chars Produced from Sugar Cane Bagasse by Carrier, Marion, Neomagus, Hein Wjp, Görgens, Johann, Knoetze, Johannes H

“…The characterization of char obtained from the vacuum pyrolysis (8 kPaabs, 460 °C, 18 °C/min) of sugar cane bagasse followed by steam gasification (60 wt % of…”
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Analytic High-Pressure Phase Equilibria. Part II: Gas Chromatography and Sampling Method Development by Fourie, Frederick C. v. N., Schwarz, Cara E., Knoetze, Johannes H.

“…The phase equilibria of supercritical CO2‐alkane‐alcohol mixtures were studied using online gas chromatography. Gas chromatograph design criteria and…”
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The influence of gas physical properties on entrainment inside a sieve tray column by Uys, Ehbenezer C., Burger, Andries J., Du Preez, Louis J., Knoetze, Johannes H.

“…•New sieve tray entrainment data for a wider range in gas phase physical properties.•At constant Fs, entrainment found to decrease for an increase in gas…”
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Reliability of methods for the determination of specific substrate consumption rates in batch culture by Görgens, Johann F., Van Zyl, Willem H., Knoetze, Johannes H.

“…Four methods for the calculation of specific substrate consumption rates in batch cultivation were compared. Calculations based on a simple mathematical model…”
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Phase Equilibria of Long-Chain Carboxylic Acids in Supercritical Propane by Schwarz, Cara E, Zamudio, Michelle, Knoetze, Johannes H

“…This paper presents data on the phase behavior of long-chain acids (octanoic acid, decanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, and…”
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Analytic Setup for Multicomponent High-Pressure Phase Equilibria via Dual Online Gas Chromatography by Fourie, Frederick C. v. N., Schwarz, Cara E., Knoetze, Johannes H.

“…A high‐pressure analytic phase equilibria setup, capable of operation at 150 °C and 30 MPa, was developed. The variable‐volume view cell contains two…”
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