scholarly journals Carbon Dioxide Absorption and Release Properties of Pyrolysis Products of Dolomite Calcined in Vacuum Atmosphere

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Fei Wang ◽  
Toshihiro Kuzuya ◽  
Shinji Hirai ◽  
Jihua Li ◽  
Te Li

The decomposition of dolomite into CaO and MgO was performed at 1073 K in vacuum and at 1273 K in an Ar atmosphere. The dolomite calcined in vacuum was found to have a higher specific surface area and a higher micropore volume when compared to the dolomite calcined in the Ar atmosphere. These pyrolysis products of dolomite were reacted with CO2at 673 K for 21.6 ks. On the absorption of CO2, the formation of CaCO3was observed. The degree of absorption of the dolomite calcined in vacuum was determined to be above 50%, which was higher than the degree of absorption of the dolomite calcined in the Ar atmosphere. The CO2absorption and release procedures were repeated three times for the dolomite calcined in vacuum. The specific surface area and micropore volume of calcined dolomite decreased with successive repetitions of the CO2absorption and release cycles leading to a decrease in the degree of absorption of CO2.

2015 ◽  
Vol 749 ◽  
pp. 17-21 ◽  
Author(s):  
Joanna Sreńscek Nazzal ◽  
Karolina Glonek ◽  
Jacek Młodzik ◽  
Urszula Narkiewicz ◽  
Antoni W. Morawski ◽  
...  

Microporous carbons prepared from commercial activated carbon WG12 by KOH and/or ZnCl2 treatment were examined as adsorbents for CO2 capture. The micropore volume and specific surface area of the resulting carbons varied from 0.52 cm3/g (1374 m2/g) to 0.70 cm3/g (1800 m2/g), respectively. The obtained microporous carbon materials showed high CO2 adsorption capacities at 40 bar pressure reaching 16.4 mmol/g.


BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6074-6082
Author(s):  
Weikai Wang ◽  
Minghan Li ◽  
Jiabin Cai

In order to study the effects of a messmate heartwood extraction process on its cell wall pore structure and its drying ability, its nanopore structure was explored after via gas adsorption technology. Specifically, the messmate heartwood particles were extracted with methanol, and then the cell wall pore structure of the original and extracted samples were evaluated by N2 and CO2 sorption and pycnometer methods, respectively. Overall, compared with the original samples, the cell wall porosity, micropore volume, mesopore volume, BET specific surface area, and specific surface area of the micropores of the extracted messmate heartwoods increased by 2.55%, 0.007 cm3/g, 0.0014 cm3/g, 0.24 m2·g-1, and 21.9 m2·g-1, respectively. The cell wall pore volume measured via the gas adsorption method was smaller than the measurement from the pycnometer method. The results indicated that the presence of extractives made the messmate cell wall have a decreased pore volume and porosity, which may be one of the reasons messmate wood is difficult to dry. Messmate extractives primarily were present in the micropores of the cell wall in the range of 0.4 nm to 0.7 nm. However, gas sorption technology could not detect all the pores in the cell wall of the messmate heartwood sample.


RSC Advances ◽  
2018 ◽  
Vol 8 (74) ◽  
pp. 42280-42291 ◽  
Author(s):  
Ling Zhang ◽  
Ling-yu Tu ◽  
Yan Liang ◽  
Qi Chen ◽  
Ze-sheng Li ◽  
...  

Activated carbon fibers with high micropore volume and large specific surface area were prepared from abundant and low-cost coconut fibers, which show excellent adsorption performances towards various dyes.


Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4989
Author(s):  
Kateřina Strejcová ◽  
Zdeněk Tišler ◽  
Eliška Svobodová ◽  
Romana Velvarská

This study focused on natural materials such as clinoptilolite (CLI), metakaolin (MK), marlstone (MRL) and phonolite (PH). Clinoptilolite is one of the most known and common natural minerals (zeolites) with a unique porous structure, metakaolin is calcined kaolin clay, marlstone is a sedimentary rock and phonolite is an igneous rock composed of alkali feldspar and other minerals. These natural materials are mainly used in the building industry (additions for concrete mixtures, production of paving, gravels) or for water purification, but the modification of their chemical, textural and mechanical properties makes these materials potentially usable in other industries, especially in the chemical industry. The modification of these natural materials and rocks was carried out by leaching using 0.1 M HCl (D1 samples) and then using 3 M HCl (D2 samples). This treatment could be an effective tool to modify the structure and composition of these materials. Properties of modified materials were determined by N2 physisorption, Hg porosimetry, temperature programmed desorption of ammonia (NH3-TPD), X-ray fluorescence (XRF), X-ray powder diffraction (XRD), diffuse reflectance infrared Fourier transform (DRIFT) and CO2 adsorption using thermogravimetric analysis (TGA). The results of N2 physisorption measurements showed that that the largest increase of specific surface area was for clinoptilolite leached using 3M HCl. There was also a significant increase of the micropore volume in the D2 samples. The only exception was marlstone, where the volume of micropores was zero even in the leached sample. Clinoptilolite had the highest acidity and sorption capacity of CO2. TGA showed that the amount of CO2 adsorbed was not significantly related to the increase in specific surface area and the opening of micropores. Hg porosimetry showed that acid leaching using 0.1 M HCl and 3 M HCl resulted in a significant increase in the macropore volume in phonolite, and during leaching using 3M HCl there was an increase of the mesopore volume. From the better properties, cost-efficient and environmental points of view, the use of these materials could be an interesting solution for catalytic and sorption applications.


2013 ◽  
Vol 423-426 ◽  
pp. 554-559 ◽  
Author(s):  
Xin Zhi ◽  
Zhan Cheng Guo

This research through the study on the properties of silicon dust, put forward in combination with lime kiln tail gas recycling carbon dioxide, preparation of precipitated silica (nanoWhite Carbon Black) of high value utilization technology, and studied and summarized process of the dissolution and precipitation by carbon dioxide. The silica fume is in amorphous form, and it has some special powder properties such as ultra fine grain size and high specific surface area and high chemical activity, these provide favorable foundation for low energy consumption process of recycling the powder. In the dissolution stage, the optimization reaction time is about 40 minutes, this time to complete the process of the reaction more than 90%. And the reaction is the fastest in the first 20 minutes, complete response 75% of the reaction. In the stage of carbonization, with increase of the concentration of the precursor, the particle diameter becomes larger, but the specific surface area of the powder will reduce, the porosity and the surface activity of it will reduce corresponding.


2009 ◽  
Vol 74 (10) ◽  
pp. 1125-1132 ◽  
Author(s):  
Danijela Sekulic ◽  
Biljana Babic ◽  
Ljiljana Kljajevic ◽  
Jelena Stasic ◽  
Branka Kaludjerovic

Activated carbon cloth dressing is an appropriate wound healing material due to its biocompatibility and adsorption characteristics. The influence of gamma radiation as a sterilization process on the adsorption and mechanical properties of activated carbon cloth was investigated. The specific surface area, micropore volume, pore size distribution, surface chemistry as well as the breaking load of activated carbon cloth before and after gamma radiation were examined. Characterization by nitrogen adsorption showed that the activated carbon cloth was a microporous material with a high specific surface area and micropores smaller than 1 nm. Gamma radiation decreased the specific surface area and micropore volume but increased the pore width. The sterilization process changed the surface chemistry quantitatively, but not qualitatively. In addition, the breaking load decreased but without any influence considering the further application of this material.


2015 ◽  
Vol 752-753 ◽  
pp. 113-118
Author(s):  
Norhaniza Yusof ◽  
Ieqmal Emeer Affandi ◽  
Norfadhilatuladha Abdullah ◽  
Ahmad Fauzi Ismail ◽  
Juhana Jaafar

This paper reported the production of precursor PAN/MnO2 nanofibers via electrospinning method and studying its microstructural properties. The nanofibers were prepared by electrospun the polymer solution of polyacrylonitrile (PAN) and Manganese Oxide (MnO2) in, N, N-Dimethylformamide as its solvent. The factors considered in this study were polymer PAN/ MnO2 concentration which will significantly affect the specific surface area, nanofibers morphology, micropore volume and diameter of the nanofibers. The nanofibers were characterized using Scanning Electron Microscopy (SEM), Brunauer Emmett and Teller (BET) surface area, and Fourier Transmission Infrared Spectroscopy (FTIR). The addition of MnO2 in polymer solution increased the specific surface area of the nanofibers up to 3.5 wt % which found to be its optimum loading. In conclusion, the precursor PAN/ MnO2 -based ACNF were successfully produced with the optimization of metal oxide loading resulting to nanofibers with higher specific surface area which will further increased its adsorption performance.


Sign in / Sign up

Export Citation Format

Share Document