scholarly journals Surface Chemical Heterogeneity of Low Rank Coal Characterized by Micro-FTIR and Its Correlation with Hydrophobicity

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 239
Author(s):  
Wei Wang ◽  
Long Liang ◽  
Yaoli Peng ◽  
Maria Holuszko
Keyword(s):  
Surface Chemistry ◽  
Functional Group ◽  
Group Composition ◽  
Contact Angles ◽  
Low Rank ◽  
Surface Chemical ◽  
Carbonyl Groups ◽  
Low Rank Coal ◽  
Different Types ◽  
Aliphatic Carbon

Micro-Fourier transform infrared (micro-FTIR) spectroscopy was used to correlate the surface chemistry of low rank coal with hydrophobicity. Six square areas without mineral impurities on low rank coal surfaces were selected as testing areas. A specially-designed methodology was applied to conduct micro-FTIR measurements and contact angle tests on the same testing area. A series of semi-quantitative functional group ratios derived from micro-FTIR spectra were correlated with contact angles, and the determination coefficients of linear regression were calculated and compared in order to identify the structure of the functional group ratios. Finally, two semi-quantitative ratios composed of aliphatic carbon hydrogen, aromatic carbon hydrogen and two different types of carbonyl groups were proposed as indicators of low rank coal hydrophobicity. This work provided a rapid way to predict low rank coal hydrophobicity through its functional group composition and helped us understand the hydrophobicity heterogeneity of low rank coal from the perspective of its surface chemistry.

scholarly journals Coalbed methane adsorption capacity related to maceral compositions

2019 ◽  
Vol 38 (1) ◽  
pp. 79-91 ◽  
Author(s):  
Langtao Liu ◽  
Chao Jin ◽  
Lei Li ◽  
Chenyang Xu ◽  
Pengfei Sun ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Coalbed Methane ◽  
Functional Group ◽  
Methane Adsorption ◽  
Low Rank ◽  
Low Rank Coal ◽  
Great Role ◽  
Adsorption Volume ◽  
Isothermal Adsorption ◽  
Enhanced Adsorption

Maceral compositions take a great role in coalbed methane adsorption. Two controversial viewpoints coexist on the effect of maceral compositions to coalbed methane adsorption. One is vitrinite has better adsorption capacity than inertinite and the other is inertinite has enhanced adsorption capacity than vitrinite. In order to clarify this issue, a series of coal samples were collected and highly purified vitrinite and inertinite concentrates were gained by heavy-fluid flotation and centrifugal separation. Isothermal adsorption experiments of methane were performed to these concentrates with equilibrium moisture and their ultimate adsorption volume were obtained finally. The results show that the adsorption capacity of vitrinite is weaker and the capacity of inertinite is stronger for low-rank coal. For high-rank coal, the adsorption capacity of vitrinite is stronger and the capacity of inertinite is weaker. Along with the increase of coal rank, the adsorption capacity of vitrinite rises gradually and the adsorption capacity of inertinite declines little by little. This result shows that the adsorption capacity of coal to methane not only relates to contents of vitrinite and inertinite, but also relates to metamorphic grade of the coal, because with the increase of metamorphism of coal, molecular structure, functional group and pore characteristic of vitrinite and inertinite change gradually, which results in tremendous changes in the adsorption capacity of coal.

INVESTIGATING A LINK BETWEEN LOW-RANK COAL BEARING CARRIZO-WILCOX AQUIFER WATER AND KIDNEY DISEASE IN EAST TEXAS

2018 ◽  
Author(s):  
Jayeeta Chakraborty ◽  
◽  
Robert B. Finkelman ◽  
William H. Orem ◽  
Matthew S. Varonka ◽  
...  
Keyword(s):  
Kidney Disease ◽  
Low Rank ◽  
East Texas ◽  
Low Rank Coal

scholarly journals Analysis of the Pyrolytic Behaviour of Birch, Maple, and Rowan Leaves

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2091
Author(s):  
Valentina Zubkova ◽  
Andrzej Strojwas ◽  
Marcin Bielecki
Keyword(s):  
Combustion Products ◽  
Carbonyl Groups ◽  
Chemical Parameters ◽  
Chemical Reagents ◽  
Urban Greenery ◽  
Volatile Products ◽  
Different Types ◽  
Ft Ir ◽  
Xrd Techniques ◽  
Lower Contribution

A research study was conducted on the thermal behaviour of leaves of urban greenery (birch, maple, and rowan) and the products of their pyrolysis and extraction as assisted by microwaves. The obtained products of pyrolysis and extraction were investigated with the use of FT-IR and UV spectroscopies and XRD techniques. A contractive analysis of samples of chars, condensates, after-extraction residue, and extracts showed that the changes in structural-chemical parameters of leaves of different types of trees during pyrolysis and extraction take place in distinct ways. About 22% of material was removed from birch leaves during extraction, and more than 17% of material was extracted from maple and rowan leaves. It was determined that, during pyrolysis of after-extraction residue of leaves, many fewer PAH compounds with carbonyl groups along with alcohols and phenols are emitted than during pyrolysis of non-extracted leaves. Taking into account that pyrolysis is the first stage of combustion, a decrease in the amount of dangerous compounds in the volatile products of pyrolysis leads to a lower contribution of such compounds in combustion products. This indicates that leaves of urban greenery can be subjected to combustion after extraction, and the obtained extracts can be used as a source of phytochemicals and chemical reagents.

Transformation of low-rank coal to clean syngas and power via thermochemical route

Energy ◽  
2021 ◽  
pp. 121505
Author(s):  
Muflih A. Adnan ◽  
Arif Hidayat ◽  
Mohammad M. Hossain ◽  
Oki Muraza
Keyword(s):  
Low Rank ◽  
Low Rank Coal
Sign in / Sign up

Export Citation Format

Share Document