| 1. |
- Yuan, Na-Juan, et al.
(author)
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A Study of Mn(II) Ion Capture by Mesoporous Silica
- 2011
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In: Adsorption Science and Technology. - : Hindawi Limited. - 0263-6174 .- 2048-4038. ; 29:4, s. 345-356
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Journal article (peer-reviewed)abstract
- The removal of Mn(II) ions from water using mesoporous silica as the adsorbent material is discussed. The mesoporous silica was prepared in an economic manner through the use of sodium silicate as an inexpensive source of silica and decaoxyethylene cetyl ether [C-16(EO)(10)] as the template agent. The properties of the material were characterized and its adsorption capacity for Mn(II) ions from aqueous solution investigated by varying parameters such as the pH of the initial suspension, the contact time, the initial concentration of Mn(II) ions in the solution and the adsorbent dosage. With no subsequent modification, the prepared materials exhibited a high adsorption capability towards Mn(II) ions with q(e) = 44 mg/g. The adsorption isotherms could be described by both the Langmuir and Freundlich models, the former model providing a better representation of the adsorption process. Characterization using UV-vis spectroscopy, nitrogen sorption isotherms and thermogravimetric analysis after adsorption indicated that the Mn(II) ions were adsorbed onto the mesoporous silica surface.
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| 2. |
- da S. Ramos, Alessandro, et al.
(author)
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Comparative assessment between different sample preparation methodologies for PTGA CO2 adsorption assays—Pellet, powder, and fragment samples
- 2018
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In: Adsorption Science and Technology. - : Sage Publications. - 0263-6174 .- 2048-4038. ; 36:7-8, s. 1441-1455
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Journal article (peer-reviewed)abstract
- The carbon dioxide sorption process at coal seams is very important for understanding the trapping mechanisms of carbon capture and storage. The gas retention capacity of coal seams can be estimated using indirect methods based on the adsorption/desorption isotherms obtained in the laboratory. However, the gas sorption capacity can be overestimated or underestimated depending on the sample preparation. This work evaluates different sample preparations and their theoretical adsorption capacity using coal samples from the Cambui coal field (Parana Basin), southern Brazil. Experiments using a thermogravimetric balance were done to calculate the theoretical adsorption capacity, while sample characterization was done through immediate analysis, elementary analysis, and mineralogical studies. The sample preparations used in this work were powder, pellets, and fragments. While the powder form presents an average behavior, without any experimental complication, the pellet is extremely sensitive to any variation in the sample preparation, such as fractures, and the fragment requires a much longer experiment time than the other sample preparations, being impracticable for some cases.
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| 3. |
- Tasca, Andrea Luca, et al.
(author)
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Novel hydrophilic and hydrophobic amorphous silica : Characterization and adsorption of aqueous phase organic compounds
- 2018
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In: Adsorption Science and Technology. - : SAGE PUBLICATIONS INC. - 0263-6174 .- 2048-4038. ; 36:1-2, s. 327-342
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Journal article (peer-reviewed)abstract
- Very few studies have investigated the adsorption performance of hydrophobic and hydrophilic silicas with dissolved organics in water, which is a required final step during produced water treatment. The cost of functionalization also hinders the use of hydrophobic materials as sorbents. Novel hydrophilic silicas, prepared at low temperature and ambient pressure, were characterised by SEM, FTIR and BET analysis, and studied for the adsorption of aqueous phase organic compounds at concentrations below their solubility limits. Adsorption capacities were found to be up to 264 mg/g for benzene and 78.8 mg/g for toluene. Direct comparison is made with the analogous hydrophobic version of one of the silica materials, demonstrating comparable uptakes for benzene concentrations lower than 50 mg/L. This finding supports the hypothesis that, at very low aqueous phase organic concentrations, hydrophobicization has no discernible effect on access of the pollutants to the internal porosity of the material.
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| 4. |
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