Physical Changes in the Pore Structure of Coal with Chemical Processing
Physical Changes in the Pore Structure of Coal with Chemical Processing

Author:

Publisher:

Published: 1978

Total Pages:

ISBN-13:

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The physical structure of Roland Seam coal was characterized by studying the surface areas, pore volumes, and pore distributions of raw coal, extracted coals, and reacted coals. BET surface areas were measured by carbon dioxide adsorption at 195°K and nitrogen adsorption at 77°K. Pore volumes were calculated by the difference in the reciprocals of measured apparent and actual densities. Distribution curves were generated by measuring mercury penetration as a function of pressure. The data gathered suggests a micropore structure having a 34 A average diameter and random constrictions of the order of 4 A. Extraction generates new micropores and degrades the micropore structure. Changes in the pore distribution and the generation of new pores indicate that resistance to extraction due to the pore structure is minimal, while pore-volume data confirm the preferential liquefaction of lower-molecular-weight material. Increases in surface roughness due to pretreatment of the coal indicate a higher selectivity of solvents after hydrogenation of the coal. A study of the BET constant implies that the surface becomes more favorable to carbon dioxide adsorption with increasing extraction.

Carbon and Coal Gasification
Carbon and Coal Gasification

Author: J.L. Figueiredo

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 649

ISBN-13: 9400943822

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Carbon gasification reactions form the basis of many important industrial processes, such as the combustion of coal and the produc tion of synthesis gas, fuel gases and activated carbons. They are also involved in metallurgical processes and in the regeneration of coked catalysts. Thus, understanding the fundamentals of carbon gasification is of vital importance for further technological development. Moreover, the subject is of interdisciplinary nature, involving chemistry, ma terials science and chemical engineering. Therefore, it was thought that an Advanced Study Institute would be fruitful in establishing the state of the art, in bringing together experts from the various sectors involved and in identifying areas of required research and industrial development. Such a meeting was held at Alvor, Portugal, from the 20th to the 31st May 1985, and the lectures presented the reof are collected in this volume. The present volume is organized in seven chapters. The Intro duction presents the carbon gasification reactions an~ their rele vance for particular processes and industrial uses. In the second chapter, the structures of carbon and coal are reviewed, together with methods of structural, chemical and textural characterization.