Sorption of saturated and unsaturated hydrocarbons on selected coal sample from the Pniówek mine

Abstract

Type, amount and composition of gases which form in rocks and coals during a metamorphism process depend on a number of factors in particular genetic type of original matter, way and conditions of its gathering, temperature, pressure and geological time. Sorption tests were done by the volumetric method, with the use of adsorption micro-burettes. A major advantage of the measurement set-up is that the surplus amounts of adsorbate can be used in experiments, which is of particular importance when handling sorbents with heterogeneous structure, such as hard coals. Sorbates used in the test program were the vapours of hexane, hex-1-ene, heptane, hept-1-ene, octane and benzene. Measurement results seem to corroborate the hypothesis that sorption of polar substance vapours is chiefly a surface process. Polarity of hard coals, mostly associated with the presence of reactive oxygen groups (nitrogen and sulphuric groups), largely affects the sorption of polar substances and in a most characteristic manner controls the sorption of apolar ones. In the case of the latter, sorption is induced by the action of the dispersive interaction force between the coal surface and the sorbate's polar molecules. The pattern of sorption isotherms indicates that the presence of dual bond affects the sorbent-sorbate interactions and hence the sorption capacity of investigated coals.

Vapour Sorption on Coal: Influence of Polarity and Rank

“…Krzy żanowski and Zarębska [29] carried out measurements of n-heptane and 1-heptene vapour sorption in bituminous coals and concluded that the sorption of vapours of apolar substances is mainly surface-bound and significantly depends on the porosity of coals and that the presence of a double bond influences the sorbent-sorbate type interactions and the sorption capacity. These results were confirmed by Baran and co-workers [12] who performed sorption studies of hexane, 1-hexene, heptane, 1-heptene, octane, and benzene vapours on low-rank bituminous coal.…”

“…The paper is a continuation of research carried out in the Adsorption and Environmental Engineering Group, Faculty of Energy and Fuels, AGH University of Science and Technology. The publication combines information presented in previous works of the team [8,9,12,29] with new, unpublished data to summarize, expand and systemise information on the sorption of water vapour, methanol vapour, and saturated and unsaturated hydrocarbons: hexane, 1-hexene, heptane, 1-heptene, and octane, on bituminous coal.…”

“…The reasons lie in the theoretical and practical aspects from the point of view of the natural environment of the sorbent, the original conditions of its occurrence, and the conditions under which the sorbent is used. The coal substance has the ability to sorb low molecular weight substances such as water vapour [1][2][3][4][5][6][7], methanol vapour [8][9][10][11], and hydrocarbons [12][13][14][15][16][17]. The process can occur on its surface by physical bonding (physical adsorption) or by formation of covalent chemical bonds (chemical adsorption, chemisorption) or by volumetric absorption that affects its structure (absorption).…”

A study of dynamic adsorption of propylene and ethylene emitted from the process of coal self-heating

“…The tendency of gaseous components of mine air to amass on the surface of coal has been previously investigated by means of determining maximum adsorption capacity of coal in relation to single fire gases using the static adsorption technique 14–17 . It has been reported that the contact of gaseous products of the thermal oxidation reaction of coal with an adsorbent such as coal can effectively cause their adsorption in various amounts.…”

Effect of porous structure of coal on propylene adsorption from gas mixtures

“…In a number of published research papers [30][31][32][33] , the adsorption of gases most frequently used in fire risk assessment was discussed. In most of the studies the adsorption of a single gas on coal or the mixture of carbon dioxide and methane as an adsorbant was measured, and only in the context of methane recovery.…”