Ludmila Butuzova

Thermochemical and geochemical characteristics of sulphur coals

Abstract Gas chromatography–mass spectrometry (GC-MS) method was applied for investigation of the extracts obtained from three pairs of Donets bituminous coals (76–79% of C daf ) of similar rank but differing in sulphur content. The elemental characteristic of the coals and hydrocarbon composition of their extracts reflect the differences in the environments of sulphur coals formation and differences in their structure. The thermal and natural coalification pathways of low- and high-sulphur coals formed under low-reduced and reduced conditions during early diagenesis were determined.

The effect of water on the yield and structure of the products of brown coal pyrolysis and hydrogenation

The influence of various methods of Kansko-Achinsk brown coals humidification on their behaviour during pyrolysis and hydrogenation is investigated. Variations of derivatographic data, X-ray and DRIFT features of solid pyrolysis residues are presented. The hydrogenation liquid and gas products are studied by gas chromatography, gas chromatography-mass spectrometry and 1NMR spectroscopy. It was shown that part of the moisture is irreversible bound with coal, which participates in thermal hydrolysis reactions and produces the change in the polycyclic aromatic skeleton which is accompanied by a greater change in the yield of pyrolysis and hydrogenation products.

Thermodestruction of brown coals of different genetic types

The influence of brown coal genetic type and method of chemical pre-treatment on its behavior in pyrolysis processes has been shown. An important role of brown coal reductivity in coal thermal decomposition has been ascertained. It has been found that chemical pre-treatment permits variation of the rate of pyrolysis, the yields of pyrolysis products and structure of semi-cokes.

The influence of a method of brown coal chemical modification on its behaviour in the pyrolysis processes

Abstract The influence of various methods of chemical treatment of coal on its behaviour in inert media and in water vapour has been shown. It has been found that during pyrolysis in inert medium, chemical modification permits variation of the yields of pyrolysis products over a wide range. The attack of coal organic matter (COM) by the water molecule becomes a principal reaction in water vapour. Evidence in favour of the hypothesis for chemical interaction of water vapour with COM paramagnetic centres (PMC) has been obtained.

Influence of oxygen on the behaviour of oxygen-containing groups of soft coal in pyrolysis

Abstract A comparison has been made of the processes of thermal and thermo-oxidative decomposition of Kansk-Achinsk brown coal. The composition of the residues formed at different temperatures was studied by elemental and chemical functional analyses and i.r. spectrometry and X-ray diffractometry. Significant differences in the temperature-dependence of gain or loss rates were observed for individual elements, functional groups, molecular structure parameters and the supermolecular organization of the solid products, depending on the gas atmosphere. These differences are mostly due to the fact that with limited access of aerial oxygen, coal degradation proceeds through partial destruction of the stacks of carbon networks.