Aromatic compound adsorption from aqueous solution on activated carbons^|^#8212;Effects of adsorbate polarity and surface functional groups^|^#8212;

Four cubic mesoporous silicates (CMS), one unmodified and three grafted with amine, carboxylic and cyano surface functional groups, were prepared, characterised and compared as adsorbents for tetramethyl ammonium hydroxide (TMAH) from aqueous solution. The adsorption process was studied as a function of molecular size and CMS pore volume. Sorption on the unmodified, cyano- and carboxylic-grafted adsorbents closely followed the Langmuir model while adsorption on the amine-treated silicate conformed to the Freundlich model. A comparison of the adsorbent pore volume and the volume of sorbed TMAH molecules suggested that monolayer sorption occurred, there being some evidence that surface functional groups influenced the adsorption process. The presence or absence of structural order, as defined by X-ray diffraction analysis, had no significant influence on the adsorption, as all materials, both ordered and disordered, had relatively high adsorption capacities.

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Coffee residue-based activated carbons for phenol removal

Water Practice & Technology ◽

10.2166/wpt.2021.034 ◽

2021 ◽

Author(s):

Hemavathy Palanisami ◽

Mohamad Rafiuddin Mohd Azmi ◽

Muhammad Abbas Ahmad Zaini ◽

Zainul Akmar Zakaria ◽

Muhd Nazrul Hisham Zainal Alam ◽

...

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Functional Groups ◽

High Performance ◽

Activated Carbons ◽

Phenol Removal ◽

Surface Functional Groups ◽

Maximum Capacity ◽

Second Stage ◽

Adsorptive Properties

Abstract This work was aimed to evaluate the adsorptive properties of activated carbons from coffee residue for phenol removal. The coffee residue was activated using H3PO4 and KOH, and the resultant activated carbons were characterized for surface area and functional groups. The values of surface area were recorded as 1,030 m2/g and 399 m2/g for H3PO4- and KOH-activated carbons, respectively. The maximum capacity for phenol removal is comparable for both activated carbons at 43 mg/g. The pores might be inaccessible due to electrostatic repulsion by surface functional groups and hydroxyl anions. The second stage in a two-stage adsorber design is necessary to accomplish the process with high performance and minimum dosage of activated carbon. Coffee residue is a promising activated carbon precursor for phenol removal.

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Effect of acidic surface functional groups on Cr(VI) removal by activated carbon from aqueous solution

Rare Metals ◽

10.1007/s12598-010-0059-6 ◽

2010 ◽

Vol 29 (3) ◽

pp. 333-338 ◽

Cited By ~ 10

Author(s):

Hualei Zhou ◽

Yunfa Chen

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Functional Groups ◽

Surface Functional Groups

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Surface functional groups and redox property of modified activated carbons

Mining Science and Technology (China) ◽

10.1016/j.mstc.2011.02.020 ◽

2011 ◽

Vol 21 (2) ◽

pp. 181-184 ◽

Cited By ~ 6

Author(s):

Zhang Xianglan ◽

Deng Shengfu ◽

Liu Qiong ◽

Zhang Yan ◽

Cheng Lei

Keyword(s):

Functional Groups ◽

Activated Carbons ◽

Redox Property ◽

Surface Functional Groups ◽

Modified Activated Carbons

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Study of chromium(vi) removal from aqueous solution using nitrogen-enriched activated carbon based bamboo processing residues

RSC Advances ◽

10.1039/c4ra11016a ◽

2015 ◽

Vol 5 (1) ◽

pp. 784-790 ◽

Cited By ~ 26

Author(s):

Ji Zhang ◽

Tongxin Shang ◽

Xiaojuan Jin ◽

Jianmin Gao ◽

Qiang Zhao

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Functional Groups ◽

Activated Carbons ◽

Chromium Vi ◽

Carbon Based

Nitrogen functional groups were introduced by urea and melamine onto the surface of two bamboo processing residues derived activated carbons (ACs) and Cr(vi) adsorption was investigated by changing various parameters.

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Preparation of Mesoporous Activated Carbon from Jackfruit PPI-1 Waste and Development of Different Surface Functional Groups

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.54.189 ◽

2015 ◽

Vol 54 ◽

pp. 189-200

Author(s):

T.V. Nagalakshmi ◽

K.A. Emmanuel ◽

Ch. Suresh Babu ◽

Ch. Chakrapani ◽

P. Paul Divakar

Keyword(s):

Activated Carbon ◽

Functional Groups ◽

Activated Carbons ◽

Morphological Changes ◽

Bet Surface Area ◽

Surface Functional Groups ◽

Phase Oxidation ◽

Different Temperatures ◽

Activating Agent ◽

Thermal Stability Of

Jackfruit PPI-1 variety was selected as source of lignocellulose material. Its rind and pulp waste was used as precursor for preparation of activated carbon. K2CO3 was selected as activating agent to prepare activated carbon. Various carbons were prepared by changing the impregnation ratio (IR) at different temperatures. Activated carbon prepared at 600°C and at IR1 had good BET surface area (987m2 g-1) and yield (61.97%). In order to introduce different functional groups, this carbon was divided into two parts. One part was subjected to liquid phase oxidation with 0.1N HNO3 and the other part was soaked in 0.1N KOH for 3hours. SEM, FTIR, TPD, XRD and TGA analyses were done to identify surface morphological changes, nature of functional groups and thermal stability of activated carbons.

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