Microstructure Improvement of Modified Calcium-Based Sorbents during Cyclic CO2 Capture

Limestone is modified with acetic acid solution as a CO2sorbent in order to solve the problem that the carbonation conversion of limestone decays sharply with the number of cycles. The results show that the carbonation conversion of modified limestone is much higher than original one, and it still achieves as high as 0.5 after 20 cycles. The mechanism of the carbonation conversion improvement for modified limestone was investigated by means of XRD, SEM and nitrogen adsorption instrument. It indicates that the grain size of CaO from modified limestone is smaller than original one. The acetification restrains the increase of grain size for CaO as the number of cycles increase. Sequentially, the extent of sintering for modified limestone is reduced. The fractal dimension of calcined modified limestone is higher than calcined original one. The inner surface of calcined modified limestone is much rougher and more complicated. The acetification makes limestone produce abundant pores. The surface area and pore volume of calcined modified limestone are far greater than those of calcined original one after the same cycles.

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Cyclic Carbonation Properties of CMA as CO2 Sorbent at High Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.655 ◽

2012 ◽

Vol 518-523 ◽

pp. 655-658

Author(s):

Ying Jie Li ◽

Xin Xie ◽

Chang Tian Liu ◽

Sheng Li Niu

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Pore Volume ◽

Power Plants ◽

Acetic Acid Solution ◽

Carbonation Reaction ◽

Calcium Magnesium Acetate ◽

Pore Area ◽

Calcium Magnesium ◽

Number Of Cycles

Calcium-based minerals cyclic calcination/carbonation reaction is an effective approach to CO2 capture for coal-fired power plants. It was proposed that dolomite modified with acetic acid solution, i.e. calcium magnesium acetate (CMA), acted as a new CO2 sorbent for calcination/carbonation cycles. The carbonation conversions for CMA and dolomite with the number of cycles were experimentally investigated. The cyclic conversion for CMA is much greater than that for dolomite for the carbonation at 650-700 °C. The carbonation conversion for CMA achieves as high as 0.6 after 20 cycles. CMA maintains the great conversion for calcination at 1100 °C. CMA had a better anti-sintering than dolomite. The pore volume and pore area distributions for calcined CMA are superior to those for calcined dolomite.

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Analysis of Char Specific Surface Area and Porosity from the Fast Pyrolysis of Biomass and Pulverized Coal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.608-609.383 ◽

2012 ◽

Vol 608-609 ◽

pp. 383-387 ◽

Cited By ~ 1

Author(s):

Ji Yi Luan ◽

Xue Mei Wu ◽

Gui Fu Wu ◽

Dong Wei Shao

Keyword(s):

Fractal Dimension ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Rice Husk ◽

Pore Volume ◽

Nitrogen Adsorption ◽

Pulverized Coal ◽

Wood Dust ◽

Corn Straw

In this paper, the chars of wood dust, corn straw, rice husk and coal pulverized were obtained at different residual time of various pyrolysis temperature (1173 K, 1273 K and 1373 K) during the process of flash pyrolysis in the drop tube furnace (DTF). In order to obtain the parameters of porous structure which included specific surface area, pore volume and fractal dimension of char, low-temperature nitrogen adsorption method was employed to obtain nitrogen adsorption isotherm of chars sample. For the four chars, the corn straw char had the biggest specific surface area and pore volume, the rice husk in second place, the wood dust in third place, and the pulverized coal char in the last one. By taking Frenkel-Halsey Hil (FHH) method to analyze the fractal character of char surface structure, we found that the fractal dimension of biomass except wood char is higher than those of pulverized coal char.

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Some Approaches to Viscometric Study of Chitosan in Acetic Acid Solution

Chemistry & Chemical Technology ◽

10.23939/chcht10.02.135 ◽

2016 ◽

Vol 10 (2) ◽

pp. 135-139 ◽

Cited By ~ 3

Author(s):

Valentina Chernova ◽

◽

Angela Shurshina ◽

Elena Kulish ◽

Gennady Zaikov ◽

...

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Intrinsic Viscosity ◽

Acetic Acid Solution ◽

Conformational State ◽

Macromolecular Coil ◽

Degree Of Swelling ◽

Current Value ◽

Viscometric Study

Some ways of estimating the values of the intrinsic viscosity of chitosan were analyzed. It was shown that the method of Irzhak and Baranov for estimating the current value of the intrinsic viscosity allows to adequately estimates the conformational state of the macromolecular coil and its degree of swelling.

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Study on the initiation mechanism upon oxidation of methylaromatic hydrocarbons in presence of cobalt acetate and sodium bromide in acetic acid solution

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19752084 ◽

1975 ◽

Vol 40 (7) ◽

pp. 2084-2092 ◽

Cited By ~ 2

Author(s):

S. Ivanov ◽

M. Hinkova

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Acetic Acid Solution ◽

Cobalt Acetate ◽

Sodium Bromide ◽

Initiation Mechanism

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Nanometer Pore Structure Characterization of Taiyuan Formation Shale in the Lin-Xing Area Based on Nitrogen Adsorption Experiments

Minerals ◽

10.3390/min11030298 ◽

2021 ◽

Vol 11 (3) ◽

pp. 298

Author(s):

Chenlong Ding ◽

Jinxian He ◽

Hongchen Wu ◽

Xiaoli Zhang

Keyword(s):

Specific Surface ◽

Pore Structure ◽

Surface Area ◽

Specific Surface Area ◽

Shale Gas ◽

Pore Volume ◽

Ordos Basin ◽

Total Pore Volume ◽

Nitrogen Adsorption ◽

Taiyuan Formation

Ordos Basin is an important continental shale gas exploration site in China. The micropore structure of the shale reservoir is of great importance for shale gas evaluation. The Taiyuan Formation of the lower Permian is the main exploration interval for this area. To examine the nanometer pore structures in the Taiyuan Formation shale reservoirs in the Lin-Xing area, Northern Shaanxi, the microscopic pore structure characteristics were analyzed via nitrogen adsorption experiments. The pore structure parameters, such as specific surface area, pore volume, and aperture distribution, of shale were calculated; the significance of the pore structure for shale gas storage was analyzed; and the main controlling factors of pore development were assessed. The results indicated the surface area and hole volume of the shale sample to be 0.141–2.188 m2/g and 0.001398–0.008718 cm3/g, respectively. According to the IUPAC (International Union of Pure and Applied Chemistry) classification, mesopores and macropores were dominant in the pore structure, with the presence of a certain number of micropores. The adsorption curves were similar to the standard IV (a)-type isotherm line, and the hysteresis loop type was mainly similar to H3 and H4 types, indicating that most pores are dominated by open type pores, such as parallel plate-shaped pores and wedge-shaped slit pores. The micropores and mesopores provide the vast majority of the specific surface area, functioning as the main area for the adsorption of gas in the shale. The mesopores and macropores provide the vast majority of the pore volume, functioning as the main storage areas for the gas in the shale. Total organic carbon had no notable linear correlation with the total pore volume and the specific surface area. Vitrinite reflectance (Ro) had no notable correlation with the specific surface area, but did have a low “U” curve correlation with the total pore volume. There was no relationship between the quartz content and specific surface area and total pore volume. In addition, there was no notable correlation between the clay mineral content and total specific surface area and total pore volume.

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