Molecular structure and ammonia gas adsorption capacity of a Cu(II)-1,10-phenanthroline complex intercalated in montmorillonite by DFT simulations

Covalent organic Imine polymers with intrinsic meso-porosity were synthesized by condensation reaction between 4,4-diamino diphenyl methane and (para/meta/ortho)-phthaladehyde. Even though these polymers were synthesized from precursors of bis-bis covalent link mode, the bulk materials were micrometer size particles with intrinsic mesoporous enables nitrogen as well as carbon dioxide adsorption in the void spaces. These polymers were showed stability up to 260o centigrade. Nitrogen gas adsorption capacity up to 250 cc/g in the ambient pressure was observed with type III adsorption characteristic nature. Carbon dioxide adsorption experiments reveal the possible terminal amine functional group to carbamate with CO2 gas molecule to the polymers. One of the imine polymers, COP-3 showed more carbon dioxide sorption capacity and isosteric heat of adsorption (Qst) than COP-1 and COP-2 at 273 K even though COP-3 had lower porosity for nitrogen gas than COP-1 and COP-2. We explained the trends in gas adsorption capacities and Qst values as a consequence of the intra molecular interactions confirmed by Density Functional Theory computational experiments on small molecular fragments.

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Changes in Pore Structure of Coal Caused by CS2 Treatment and Its Methane Adsorption Response

Geofluids ◽

10.1155/2018/7578967 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Run Chen ◽

Yong Qin ◽

Pengfei Zhang ◽

Youyang Wang

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Gas Adsorption ◽

Recovery Process ◽

Micropore Volume ◽

Methane Adsorption ◽

Coal Bed ◽

Methane Recovery ◽

Before And After ◽

Key Issues

The pore structure and gas adsorption are two key issues that affect the coal bed methane recovery process significantly. To change pore structure and gas adsorption, 5 coals with different ranks were treated by CS2 for 3 h using a Soxhlet extractor under ultrasonic oscillation conditions; the evolutions of pore structure and methane adsorption were examined using a high-pressure mercury intrusion porosimeter (MIP) with an AutoPore IV 9310 series mercury instrument. The results show that the cumulative pore volume and specific surface area (SSA) were increased after CS2 treatment, and the incremental micropore volume and SSA were increased and decreased before and after Ro,max=1.3%, respectively; the incremental big pore (greater than 10 nm in diameter) volumes were increased and SSA was decreased for all coals, and pore connectivity was improved. Methane adsorption capacity on coal before and after Ro,max=1.3% also was increased and decreased, respectively. There is a positive correlation between the changes in the micropore SSA and the Langmuir volume. It confirms that the changes in pore structure and methane adsorption capacity due to CS2 treatment are controlled by the rank, and the change in methane adsorption is impacted by the change of micropore SSA and suggests that the changes in pore structure are better for gas migration; the alteration in methane adsorption capacity is worse and better for methane recovery before and after Ro,max=1.3%. A conceptual mechanism of pore structure is proposed to explain methane adsorption capacity on CS2 treated coal around the Ro,max=1.3%.

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Determination of molecular structure parameters on the basis of gas-adsorption chromatography data. Part 2.—Determination of potential barriers and equilibrium angles of internal rotation for methyl derivatives of biphenyl and for terphenyls

Journal of the Chemical Society Faraday Transactions 2 Molecular and Chemical Physics ◽

10.1039/f29827802013 ◽

1982 ◽

Vol 78 (12) ◽

pp. 2013-2023 ◽

Cited By ~ 26

Author(s):

Arunas J. Grumadas ◽

Dionizas P. Poshkus ◽

Andrei V. Kiselev

Keyword(s):

Molecular Structure ◽

Internal Rotation ◽

Gas Adsorption ◽

Adsorption Chromatography ◽

Structure Parameters ◽

Potential Barriers ◽

Gas Adsorption Chromatography ◽

Methyl Derivatives ◽

Derivatives Of

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Geologic characterization of a lower Cambrian marine shale: Implications for shale gas potential in northwestern Hunan, South China

Interpretation ◽

10.1190/int-2017-0117.1 ◽

2018 ◽

Vol 6 (3) ◽

pp. T635-T647 ◽

Cited By ~ 3

Author(s):

Zhenghui Xiao ◽

Jisong Liu ◽

Jingqiang Tan ◽

Rongfeng Yang ◽

Jason Hilton ◽

...

Keyword(s):

Adsorption Capacity ◽

South China ◽

Lower Cambrian ◽

Gas Adsorption ◽

Vitrinite Reflectance ◽

Mean Value ◽

Hunan Province ◽

Quartz Content ◽

Gas Potential

We have investigated the geologic features of the lower Cambrian-aged Niutitang Shale in the northwestern Hunan province of South China. Our results indicate that the Niutitang Shale has abundant and highly mature algal kerogen with total organic carbon (TOC) content ranging from 0.6% to 18.2%. The equivalent vitrinite reflectance (equal-Ro) value is between 2.5% and 4.3%. Mineral constituents are dominated by quartz and clay. The average quartz content (62.8%) is much higher than that of clay minerals (26.1%), and this suggests a high brittleness index. Organic-matter pores, interparticle pores, intraparticle pores, interlaminated fractures, and structural fractures are all well developed. The porosity ranges from 0.6% to 8.8%, with an average of 4.8%, whereas the permeability varies from 0.0018 to [Formula: see text] (microdarcy) (averaging [Formula: see text]). The porosity of TOC- and clay-rich shale samples is generally higher than that of quartz-rich shale samples. The gas adsorption capacity of the Niutitang Shale varies from 2.26 to [Formula: see text], with a mean value of [Formula: see text]. The TOC content appears to significantly influence gas adsorption capacity. In general, TOC-rich samples exhibit a much higher adsorption capacity than TOC-poor samples.

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Comparison of chemical and thermal regeneration of aromatic compounds on exhausted activated carbon

Water Science & Technology ◽

10.2166/wst.1997.0287 ◽

1997 ◽

Vol 35 (7) ◽

pp. 279-285 ◽

Cited By ~ 22

Author(s):

P. C. Chiang ◽

E. E. Chang ◽

J. S. Wu

Keyword(s):

Molecular Structure ◽

Activated Carbon ◽

Physicochemical Properties ◽

Adsorption Capacity ◽

Aromatic Compounds ◽

Thermal Regeneration ◽

Desorption Efficiency ◽

Chemical Regeneration

In this investigation, nine typical compounds, i.e., phenol, 2-aminophenol, aniline, 2-chlorophenol, chlorobenzene, β-naphthol, naphthalene, α-naphthylamine and α-chloronaphthalene were introduced to evaluate the effects of the molecular structure and physicochemical properties of these selected adsorbates on the adsorption capacity and desorption efficiency of the activated carbon. Both the thermal and chemical regeneration methods were employed to compare the regeneration efficiencies among these adsorbates and adsorbent.

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Experimental Analysis of Pore Structure and Fractal Characteristics of Soft and Hard Coals With Same Coalification

10.21203/rs.3.rs-824436/v1 ◽

2021 ◽

Author(s):

Barkat Ullah ◽

Yuanping Cheng ◽

Liang Wang ◽

Weihua Yang ◽

Izhar Mithal Jiskani ◽

...

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Gas Adsorption ◽

Hysteresis Loops ◽

Control Measures ◽

Practical Significance ◽

Coal Bed ◽

Hard Coal ◽

Pore Surface ◽

Soft Coal

Abstract Accurate and quantitative investigation of the physical structure and fractal geometry of coal has important theoretical and practical significance for coal bed methane and the prevention of dynamic disasters such as coal and gas outbursts. This study investigates the pore structure and fractural characteristics of soft and hard coals using nitrogen and carbon dioxide (N2/CO2) adsorption. Coal samples from Pingdingshan Mine in Henan province of China were collected and pulverized to the required size (0.2-0.25mm). N2/CO2 adsorption tests were performed to evaluate the pore size distribution (PSD), specific surface area (SSA), and pore volume (PV). The pore structure was characterized based on fractural theory. The results unveiled that the strength of coal has a significant influence on pore structure and fracture dimensions. The obvious N2-adsorption isotherms of the coals were verified as Type IV (A) and Type II. The shape of the hysteresis loops indicates the presence of slit-shaped pores. There are significant differences in SSA and PV between both coals. The soft coal showed larger SSA and PV than hard coal that shows consistency with adsorption capacity. The fractal dimensions of soft coal are respectively larger than that of hard coal. The greater the value of D1 (complexity of pore surface) of soft coal is, the larger the pore surface roughness and gas adsorption capacity is. The results enable us to conclude that the characterization of pores and fractures of soft and hard coals is different, tending to different adsorption/desorption characteristics and outburst sensitivity. In this regard, results provide a reference for formulating corresponding coal and gas outburst prevention and control measures.

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The binary gas sorption in the bituminous coal of the Huaibei Coalfield in China

Adsorption Science & Technology ◽

10.1177/0263617418798125 ◽

2018 ◽

Vol 36 (9-10) ◽

pp. 1612-1628 ◽

Cited By ~ 6

Author(s):

Lei Zhang ◽

Zhiwei Ye ◽

Mingxue Li ◽

Cun Zhang ◽

Qingsheng Bai ◽

...

Keyword(s):

Adsorption Capacity ◽

Sorption Capacity ◽

Bituminous Coal ◽

Gas Adsorption ◽

Langmuir Equation ◽

Separation Coefficient ◽

Gas Sorption ◽

Langmuir Adsorption ◽

Gas Molecules ◽

Huaibei Coalfield

Knowledge of the gas sorption characteristics of a coal not only helps to explain the mechanism of enhanced coalbed methane recovery but also provides an important basis for simultaneous coal and gas extraction. In consequence, the pure and binary gas excess sorption capacity of methane, carbon dioxide, and nitrogen of bituminous coal samples derived from the Xutuan Coal Mine in Huaibei coalfield, in Anhui Province in China, was measured using the volumetric method. The fitting analysis of the pure gas Langmuir adsorption model was carried out. The binary gas excess sorption measurement showed that the final sorption capacity of bituminous samples was the same no matter what the gas adsorption order of competitive adsorption and displacement adsorption. Hence, coal gas adsorption is physical adsorption, i.e. the different adsorption and desorption process of gas molecules does not affect the final adsorption amount of coal to each component of gas. Using the fitting parameters obtained by the Langmuir equation, the extended Langmuir equation was used to predict the adsorption capacity for each component of the binary gas. The comparison between predicted adsorption capacity and measured adsorption capacity showed that the extended Langmuir equation can better describe the trend of the adsorption isotherm curves of a binary gas under different pressures. The separation coefficient and displacement coefficient were defined from Langmuir adsorption theory. The separation coefficient involves the proportion of each component in the free phase and the proportion of each component in the adsorption phase. The displacement coefficient involves the displacement ability of gas molecules at adsorption sites by free gas molecules.

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Theoretical Models To Predict Gas Adsorption Capacity on Moist Coal

Energy & Fuels ◽

10.1021/acs.energyfuels.8b04190 ◽

2019 ◽

Vol 33 (4) ◽

pp. 2908-2914 ◽

Cited By ~ 2

Author(s):

Dong Chen ◽

Zhihui Ye ◽

Zhejun Pan ◽

Yuling Tan ◽

Hui Li

Keyword(s):

Adsorption Capacity ◽

Gas Adsorption ◽

Theoretical Models

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Synthesis of Mesoporous Silica from Bottom Ash Waste for CH4 Adsorption

Materials Science Forum ◽

10.4028/www.scientific.net/msf.964.130 ◽

2019 ◽

Vol 964 ◽

pp. 130-135

Author(s):

Pradena Bhesari Fitrah Laharto ◽

Aristin Putri Kusuma Anggraini ◽

Umirul Solichah Fauzany ◽

Randy Yusuf Kurniawan ◽

Purwanti Setyaningsih Endang

Keyword(s):

Mesoporous Silica ◽

Adsorption Capacity ◽

High Temperatures ◽

Gas Adsorption ◽

Bottom Ash ◽

Gravimetric Method ◽

Basic Material ◽

Melting Method ◽

Peg 4000

The aim of this research is to synthesize mesoporous silica directly from the bottom ash waste through the melting method using alkali at high temperatures. The resulting mesoporous silica will be used as CH4 gas adsorbent. The bottom ash waste was firstly separated by Fe and Ca using 37% HCl followed by melting at high temperatures and producing silica extract. The extract will be used as the basic material for making mesoporous silica which impregnation with PEG 4000. The resulting solids will then be characterized using XRD and BET. The result of mesoporous silica was then carried out by measuring CH4 gas adsorption capacity by gravimetric method with interval temperature of 30, 40, and 50 °C and pressure of 1, 3, and 5 atm.

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Influence of doping nitrogen, sulfur, and phosphorus on activated carbons for gas adsorption of H2, CH4 and CO2

RSC Advances ◽

10.1039/c6ra06620h ◽

2016 ◽

Vol 6 (55) ◽

pp. 50138-50143 ◽

Cited By ~ 18

Author(s):

D. Li ◽

W. B. Li ◽

J. S. Shi ◽

F. W. Xin

Keyword(s):

Adsorption Capacity ◽

Gas Adsorption ◽

Activated Carbons ◽

Porous Carbons

Heteroatoms doped porous carbons were synthesized with different acids as catalysts and heteroatoms source. Heteroatoms doping enhances gas adsorption capacity.

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