The changes in average chemical composition produced in petroleum cokes resulting from pyrolysis ... more The changes in average chemical composition produced in petroleum cokes resulting from pyrolysis of petroleum residues have been studied by high resolution solid state NMR of carbon and hydrogen. Relaxation time enhancement of resolution has been used for the NMR of {sup 13}C to separate contributions associated with protonated and non-protonated carbons. The significance of information inferred separately from the carbon and the hydrogen spectra are discussed.
Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operat... more Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operations performed to improve product quality and meet environmental specifications. Such operations in-clude hydrodenitrogenation (HDN), hydrodesulphurisation (HDS), hydrodearomatisation (HDA), hydrocracking (HYC) etc., and depending on the catalyst(s) in use and processing conditions the feed oil undergoes various compositional changes. Unravelling compositional changes on a molecu-lar level during processing is important for 1) evaluating and understanding and 2) improving the effect and efficiency of the applied catalyst(s). In this study we have utilised the increased resolu-tion and peak capacity of GCGC equipped with FID/SCD or ToF-MS detectors to monitor PAC compositional changes in various refinery streams (middle and heavy distillates) experienced during hydrotreating processes. We shall present examples on the kinetics of dibenzothiophenes removal and their conversion to biphenyl...
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1981
The technique of proton-enhanced 13 C n.m.r. has turned out to be a useful tool for the study of ... more The technique of proton-enhanced 13 C n.m.r. has turned out to be a useful tool for the study of composition and structure of whole coals. In particular, four functional types of carbons can be resolved and recognized in studies on model compounds and a series of coals: polycondensed aromatic, simple aromatic, oxygen-bonded aliphatic and simple aliphatic. The principles of the techniques are described and examples given of application to model compounds, aromaticity of coals and coal processing by-products, and time-resolved changes in carbon distribution during coal processing.
Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operat... more Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operations performed to improve product quality and meet environmental specifications. Such operations in-clude hydrodenitrogenation (HDN), hydrodesulphurisation (HDS), hydrodearomatisation (HDA), hydrocracking (HYC) etc., and depending on the catalyst(s) in use and processing conditions the feed oil undergoes various compositional changes. Unravelling compositional changes on a molecu-lar level during processing is important for 1) evaluating and understanding and 2) improving the effect and efficiency of the applied catalyst(s). In this study we have utilised the increased resolu-tion and peak capacity of GCGC equipped with FID/SCD or ToF-MS detectors to monitor PAC compositional changes in various refinery streams (middle and heavy distillates) experienced during hydrotreating processes. We shall present examples on the kinetics of dibenzothiophenes removal and their conversion to biphenyl...
The changes in average chemical composition produced in petroleum cokes resulting from pyrolysis ... more The changes in average chemical composition produced in petroleum cokes resulting from pyrolysis of petroleum residues have been studied by high resolution solid state NMR of carbon and hydrogen. Relaxation time enhancement of resolution has been used for the NMR of {sup 13}C to separate contributions associated with protonated and non-protonated carbons. The significance of information inferred separately from the carbon and the hydrogen spectra are discussed.
Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operat... more Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operations performed to improve product quality and meet environmental specifications. Such operations in-clude hydrodenitrogenation (HDN), hydrodesulphurisation (HDS), hydrodearomatisation (HDA), hydrocracking (HYC) etc., and depending on the catalyst(s) in use and processing conditions the feed oil undergoes various compositional changes. Unravelling compositional changes on a molecu-lar level during processing is important for 1) evaluating and understanding and 2) improving the effect and efficiency of the applied catalyst(s). In this study we have utilised the increased resolu-tion and peak capacity of GCGC equipped with FID/SCD or ToF-MS detectors to monitor PAC compositional changes in various refinery streams (middle and heavy distillates) experienced during hydrotreating processes. We shall present examples on the kinetics of dibenzothiophenes removal and their conversion to biphenyl...
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1981
The technique of proton-enhanced 13 C n.m.r. has turned out to be a useful tool for the study of ... more The technique of proton-enhanced 13 C n.m.r. has turned out to be a useful tool for the study of composition and structure of whole coals. In particular, four functional types of carbons can be resolved and recognized in studies on model compounds and a series of coals: polycondensed aromatic, simple aromatic, oxygen-bonded aliphatic and simple aliphatic. The principles of the techniques are described and examples given of application to model compounds, aromaticity of coals and coal processing by-products, and time-resolved changes in carbon distribution during coal processing.
Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operat... more Hydrotreatment using adequate or tailor made catalysts is a vital process in most refinery operations performed to improve product quality and meet environmental specifications. Such operations in-clude hydrodenitrogenation (HDN), hydrodesulphurisation (HDS), hydrodearomatisation (HDA), hydrocracking (HYC) etc., and depending on the catalyst(s) in use and processing conditions the feed oil undergoes various compositional changes. Unravelling compositional changes on a molecu-lar level during processing is important for 1) evaluating and understanding and 2) improving the effect and efficiency of the applied catalyst(s). In this study we have utilised the increased resolu-tion and peak capacity of GCGC equipped with FID/SCD or ToF-MS detectors to monitor PAC compositional changes in various refinery streams (middle and heavy distillates) experienced during hydrotreating processes. We shall present examples on the kinetics of dibenzothiophenes removal and their conversion to biphenyl...
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Papers by D. Whitehurst