Change of Pore-Fracture Structure of Anthracite Modified by Electrochemical Treatment Using Micro-CT

The electrochemical method can strengthen gas desorption and seepage from coal. The study on change of the pore-fracture structure of coal after electrochemical modification can help to reveal the mechanism. Anthracite was modified by the electrochemical method using our own self-developed experiment apparatus. The pore-fracture structure of modified samples was measured by micro-CT. Combined with the Matlab software, its characteristics such as pore number, porosity, and average pore diameter were analyzed. The results show that (1) the number of fractures in modified coal samples increases. The shape of new fractures in samples in the anodic and cathodic zones was irregular voids and striola, respectively. The effect of electrochemical treatment on the section of samples close to the electrode is relatively obvious. (2) With increasing pore size, the number of pores in samples changes according to negative exponential rules. After electrochemical modification, the porosity of modified samples in the anodic zone increases from 11.88% to 31.65%, and the porosity of modified samples in the cathodic zone increases from 12.13% to 36.71%. (3) The main reason for the increase in the number of pores of coal samples in the anodic and cathodic zones is the treatment of electrolytic dissolution of minerals and electrophoretic migration of charged particles, respectively.

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Electrochemical Treatment of Graphene

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.799.197 ◽

2019 ◽

Vol 799 ◽

pp. 197-202

Author(s):

Alexander Usikov ◽

Mike Puzyk ◽

Sergey Novikov ◽

Iosif Barash ◽

Oleg Medvedev ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Partial Oxidation ◽

Electrochemical Method ◽

Counter Electrode ◽

Reference Electrode ◽

Electrochemical Treatment ◽

Complete Dissolution ◽

Graphene Films ◽

Working Electrode ◽

Electrode Cell

Treatment of graphene/SiC dies in inorganic electrolytes (KOH, KCl and Na2SO4) is discussed. An electrochemical method based on the cyclic voltammetry in a conventional three-electrode cell with Ag/AgCl reference electrode, a platinum counter electrode, and the graphene/SiC dies as working electrode (anode) is used for the treatment. It was observed either partial oxidation of graphene or its complete dissolution with the formation of CO2. The treatment performed resulted in the deterioration of the graphene films and change of the graphene-die resistivity depending on the range of the scanning potential applied to the graphene/SiC dies.

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Change in the Mechanic Properties and Electrical Resistivity of High Water Backfill Material under Electrochemical Treatment

Advances in Materials Science and Engineering ◽

10.1155/2020/3248294 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Dongdong Chen ◽

Yaohui Sun ◽

Shengrong Xie ◽

En Wang ◽

Xiaoyu Wu ◽

...

Keyword(s):

Electrical Resistivity ◽

Elastic Modulus ◽

Engineering Application ◽

Deformation Modulus ◽

Potential Gradient ◽

High Water ◽

Electrochemical Treatment ◽

Uniaxial Compression Strength ◽

Electrochemical Modification ◽

Backfill Material

To modify the mechanic properties of high water backfill material (HWBM) for its engineering application in mining backfill, a series of experiments were performed to investigate the effects of electrochemical treatment on the mechanic properties and electrical resistivity of the HWBM at the early age. Meanwhile, the effects of the potential gradient, power-on time, and water–cement ratio (W/C) on electrochemical modification efficiency were investigated. The results show that the uniaxial compression strength (UCS), elastic modulus, and deformation modulus of the HWBM all first increased and then decreased after electrochemical treatment with the increasing of the potential gradient and power-on time. However, for the HWBM with different W/C, the UCS and electrical resistivity both increased the HWBM except when the W/C was 3 : 1. The elastic modulus and deformation modulus of the samples both increased after electrochemical modification except when the W/C was 4 : 1. Additionally, there is a positive correlation between the UCS and electrical resistivity in HWBM samples. Therefore, it is proved that the electrochemical technology is a potential method for improving the physicochemical properties of the HWBM.

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Mechanism and Effect of Electrochemical Modification on Physicochemical Soft Rock

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.2275 ◽

2011 ◽

Vol 415-417 ◽

pp. 2275-2280 ◽

Cited By ~ 2

Author(s):

Jian Sheng Li ◽

Dong Wang ◽

Guan Xian Kang ◽

Tian He Kang

Keyword(s):

Physicochemical Property ◽

Clay Minerals ◽

Electrochemical Method ◽

Soft Rock ◽

The Other ◽

Electrochemical Modification ◽

Structures And Properties ◽

Soft Rock Roadway ◽

Cation Substitutions ◽

Rock Roadway

Two mechanisms about electrochemical modification of clay minerals are summarized: one of electroosmotic dewatering and stabilization and the other of cation substitutions, structures and properties change, forming new minerals. The analyses of physicochemical soft rock (PCSR) indicate that physicochemical property of PCSR is dominated by physicochemical property of clay minerals. Therefore, it is possible to indurate PCSR in the coal-mine soft rock roadway with the electrochemical method.

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Electrochemical treatment of textile wastewater

Water Science & Technology ◽

10.2166/wst.1996.0258 ◽

1996 ◽

Vol 34 (11) ◽

pp. 17-24 ◽

Cited By ~ 35

Author(s):

J. Naumczyk ◽

L. Szpyrkowicz ◽

F. Zilio-Grandi

Keyword(s):

Electrochemical Method ◽

Textile Wastewater ◽

Electrochemical Treatment ◽

High Concentration ◽

Butanoic Acid ◽

Indirect Oxidation ◽

Organics Removal ◽

Ms Analysis ◽

Oxidation Of Organics

The treatment of textile wastewater, containing a high concentration of Cl- ion, by an electrochemical method using Ti/RuO2, Ti/Pt and Ti/Pt/Ir electrodes is investigated. All three anodes proved to be very effective in direct or indirect oxidation of organics present in the wastewater. After 60 min of electrolysis at 6 A/dm2, COD was reduced by 85-92% and DOC by about 85%. Of the three electrodes tested, the efficiency of organics removal followed the order: Ti/RuO2 > Ti/Pt > Ti/Pt/Ir. The electrochemical treatment of textile wastewater resulted in the production of many chloroorganics in high concentration. GC-MS analysis showed the presence of the following major products: 1,1-dichlorocyclopentene, 2,3-dichloro-2-methylbutane, chloromethylsilane, 2,3-dichloro-2-methyl butanoic acid, 2,3-dichloro-2-methyl propanol, 2,3-dimethyl-2, 3-butanediol and 2-butylphenol.

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Experimental and mechanistic research on methane adsorption in anthracite modified by electrochemical treatment using selected electrode materials

Scientific Reports ◽

10.1038/s41598-019-53840-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Xiaoyu Zhang ◽

Runxu Zhang ◽

Tianhe Kang ◽

Yaoqing Hu ◽

Chao Li

Keyword(s):

Free Energy ◽

Electrode Materials ◽

Graphite Electrode ◽

Electrochemical Treatment ◽

Methane Adsorption ◽

Aluminum Electrode ◽

Electrochemical Modification ◽

Iron Copper ◽

Methane Extraction ◽

Adsorption Of Methane

AbstractThe strong adsorption capacity of methane in anthracite can seriously affect the methane extraction. Electrochemical treatment is an effective way to weaken the capacity of methane adsorption in coal. Iron, copper, aluminum and graphite as four kinds of electrode materials were selected to modify anthracite by electrochemical treatment. The adsorption of methane in anthracite, before and after modification, was tested under different adsorption pressure. Based on the changes of pore characteristics and chemical groups of anthracite, the modification process of different electrode materials was analyzed. The results showed that after electrochemical modification, the adsorption of methane decreased, when the graphite electrode was used, the methane adsorption decreases the most, followed by copper and iron electrodes, and the aluminum electrode decreased the least. After electrochemical modification using aluminum, iron, copper and graphite electrodes, the Langmuir constant a reduced by 5.22%, 8.48%, 9.24% and 11.33%, respectively, and the degree of reduction is graphite > copper > iron > aluminum. After electrochemical modification using the graphite electrode, the Langmuir constant b was reduced by 23.52%. On the contrary, after electrochemical modification using the mental electrodes, the Langmuir constant b was increased by about 5%. The surface free energy of anthracite decreased with the adsorption of CH4, the higher the pressure, the more the free energy decreased, and the reduction of surface energy decreased after electrochemical modification. The difference of the electrode reactions was the main reason for the electrochemical results, the Mn+ ions generated in the anode changed the properties of the clay mineral in the coal, and the H+ ions corroded the calcite minerals in the coal. The results obtained from this work indicate that the selection of electrode materials is crucial for the electrochemical modification, and graphite electrode is optimum for anthracite when accelerating methane extraction by electrochemical method.

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Numerical Simulation of Matrix Swelling and Its Effects on Fracture Structure and Permeability for a High-Rank Coal Based on X-ray Micro-CT Image Processing Techniques

Energy & Fuels ◽

10.1021/acs.energyfuels.0c01903 ◽

2020 ◽

Vol 34 (9) ◽

pp. 10801-10809

Author(s):

Qingzhong Zhu ◽

Xianglong Wang ◽

Yinqing Zuo ◽

Jienan Pan ◽

Yiwen Ju ◽

...

Keyword(s):

Numerical Simulation ◽

Image Processing ◽

High Rank ◽

Ct Image ◽

Micro Ct ◽

X Ray ◽

Image Processing Techniques ◽

Fracture Structure ◽

Processing Techniques

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ELECTROCHEMICAL TREATMENT OF CHEMICAL INDUSTRY WASTEWATER USING STEEL AND TIRUO2 ELECTRODES

Holos Environment ◽

10.14295/holos.v6i1.199 ◽

2006 ◽

Vol 6 (1) ◽

pp. 01

Author(s):

Gisela C. Régis ◽

Edério D. Bidoia

Keyword(s):

Efficient Method ◽

Chemical Industry ◽

Electrochemical Method ◽

Electrochemical Treatment ◽

Cellular Viability ◽

Steel Electrode ◽

Molecular Changes ◽

Electrolytic Process ◽

Biological Toxicity ◽

Industry Wastewater

The treatment of chemical industry wastewater by an electrochemical method was investigated using steel and TiRuO2 electrodes. Visible-UV spectrophotometric analyses have been performed in samples electrolyzed at 0, 10, 20, 30 and 40 min to determine the molecular changes in the wastewater. Although the steel electrode caused changes in molecules present in the raw effluent, the TiRuO2 electrode showed to promote more significant changes. It has been observed an increase in the cellular viability after electrolysis; this could be a decrease in the biological toxicity after the treatment. The electrolytic process is an efficient method to modify persistent molecules, normally, found in wastewater of rubber chemical industry and, turn then biocompatible to the environment.

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