Reactive Black dye adsorption/desorption onto different adsorbents: Effect of salt, surface chemistry, pore size and surface area

The porous structure of the materials was determined using the surface area and pore size analyzer (JW-BK132F) by N2 adsorption–desorption isotherms at 77 K.

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The Removal of Reactive Red 141 from Wastewater: A Study of Dye Adsorption Capability of Water-Stable Electrospun Polyvinyl Alcohol Nanofibers

Autex Research Journal ◽

10.2478/aut-2019-0040 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

Çigdem Akduman ◽

Seniha Morsümbül ◽

Emriye Perrin Akçakoca Kumbasar

Keyword(s):

Polyvinyl Alcohol ◽

Pore Size ◽

Surface Area ◽

Dye Adsorption ◽

Size Analysis ◽

Pore Size Analysis ◽

Electrospinning Method ◽

Nanofiber Membranes ◽

Nanofibrous Membranes ◽

Adsorption Capability

Abstract The dye production and its use in textile and related industries resulted in discharge of dye to wastewater. Adsorption for color removal is known as equilibrium separation process, and the resultant decolorization is influenced by physicochemical factors such as adsorbent surface area. The nanofiber membranes prepared by the electrospinning method have controllable nanofiber diameter and pore size distribution (PSD) with a high surface area to volume or mass ratio. In this study, polyvinyl alcohol (PVA) nanofibrous membranes were prepared by the electrospinning method at different collection times such as 3, 5 and 10 h and heat fixated at 130, 150 and 170°C for 10 min, and then, the adsorption capability of PVA nanofiber membranes for Reactive Red 141 from aqueous solution was investigated. In order to make PVA nanofibers stable to water, the nanofibrous membranes were chemically cross-linked by a polycarboxylic acid (1,2,3,4 butanetetracarboxylic acid (BTCA)). PVA nanofibrous membranes were characterized by scanning electron microscopy, thermogravimetric analysis, swelling tests and pore size analysis. The results indicated that BTCA crosslinking improved the thermal and water stability of the nanofibrous structure but has no significant effect on the pore sizes of the membranes. Adsorption of Reactive Red 141 was studied by the batch technique, and it was observed that PVA nanofibers removed approximately >80% of the dye.

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Carbonization of Lignin Extracted from Liquid Waste of Coconut Coir Delignification

Indonesian Journal of Chemistry ◽

10.22146/ijc.46484 ◽

2020 ◽

Vol 20 (4) ◽

pp. 842

Author(s):

Widiyastuti Widiyastuti ◽

Mahardika Fahrudin Rois ◽

Heru Setyawan ◽

Siti Machmudah ◽

Diky Anggoro

Keyword(s):

Pore Size ◽

Surface Area ◽

Liquid Waste ◽

Nitrogen Adsorption ◽

Nitrogen Atmosphere ◽

Precipitation Method ◽

X Ray Diffraction ◽

Coconut Coir ◽

Xrd Patterns ◽

Adsorption Desorption

Lignin as a by-product of the pulping process is less widely used for worth materials. In this study, the utilization of lignin by-product of the soda delignification process of coconut coir converted to the activated carbon by a simple precipitation method followed by the carbonization at various temperatures is presented. The by-product liquor of the soda delignification process having a pH of 13.4 was neutralized by dropping of hydrochloric acid solution to achieve the pH solution of 4 resulting in the lignin precipitation. The precipitated was washed, filtered, and dried. The dried lignin was then carbonized under a nitrogen atmosphere at various temperatures of 500, 700, and 900 °C. The dried lignin and carbonized samples were characterized using SEM, XRD, FTIR, and nitrogen adsorption-desorption analyzer, to examine their morphology, X-Ray diffraction pattern, chemical bonding interaction, and surface area-pore size distribution, respectively. The characterization results showed that the functional groups of lignin mostly disappeared gradually with the increase of temperature approached the graphite spectrum. The XRD patterns confirmed that the carbonized lignin particles were amorphous and assigned as graphitic. All samples had a pore size of 3–4 nm classified as mesoporous particles. This study has shown that the carbonization lignin at a temperature of 700 °C had the highest surface area (i.e. 642.5 m2/g) in which corresponds to the highest specific capacitance (i.e. 28.84 F/g).

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A Convenient Strategy to Control the Specific Surface Area of the Mesoporous Silica by Using the Poly(pseudo)rotaxanes Template

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.1685 ◽

2012 ◽

Vol 602-604 ◽

pp. 1685-1688

Author(s):

Lei Zu ◽

Yu Yuan Zhi ◽

Kai Gu ◽

Hui Qin Lian ◽

Xiu Guo Cui

Keyword(s):

Mesoporous Silica ◽

Specific Surface ◽

Pore Size ◽

Surface Area ◽

Specific Surface Area ◽

Fourier Transformation ◽

Silica Particle ◽

N2 Adsorption ◽

Adsorption Desorption ◽

Mesoporous Silica Particle

The poly(pseudo)rotaxanes formed by β-CD and F127 was used as the template to prepare the mesoporous silica. The specific surface area, pore size distribution and pore volume of the mesoporous silica could be controlled by simply changing the poly(pseudo)rotaxanes forming time. A series of samples with different template forming time were prepared to investigate the various specific surface area and pore size of the mesoporous silica. The morphology, composition, specific surface area and pore size of the mesoporous silica particle were investigated by the scanning electron microscopy, Fourier transformation infrared spectroscope, and N2 adsorption–desorption measurement.

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Lignin Based Activated Carbon Using H3PO4 Activation

Polymers ◽

10.3390/polym12122829 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2829

Author(s):

Zhongzhi Yang ◽

Roland Gleisner ◽

Doreen H. Mann ◽

Junming Xu ◽

Jianchun Jiang ◽

...

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Low Cost ◽

High Surface ◽

High Surface Area ◽

Dye Adsorption ◽

Nitrogen Adsorption ◽

Bet Surface Area ◽

Surface Areas ◽

Adsorption Desorption

Activated carbon (AC) with a very high surface area of over 2000 m2/g was produced from low sulfur acid hydrotropic lignin (AHL) from poplar wood using H3PO4 at a moderate temperature of 450 °C (AHL-AC6). ACs with similar surface areas were also obtained under the same activation condition from commercial hardwood alkali lignin and lignosulfonate. Initial evaluation of AC performance was carried out using nitrogen adsorption-desorption and dye adsorption. AHL-AC6 exhibited the best specific surface area and dye adsorption performance. Furthermore, the adsorption results of congo red (CR) and methylene blue (MB) showed AHL-AC6 had greater adsorption capacity than those reported in literature. The dye adsorption data fit to the Langmuir model well. The fitting parameter suggests the adsorption is nearly strong and near irreversible, especially for MB. The present study for the first time provided a procedure for producing AC from lignin with Brunauer–Emmett–Teller (BET) surface area >2000 m2/g using low cost and low environmental impact H3PO4 at moderate temperatures.

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pyGAPS: A Python-Based Framework for Adsorption Isotherm Processing and Material Characterisation

10.26434/chemrxiv.7970402.v1 ◽

2019 ◽

Author(s):

Paul Iacomi ◽

Philip L. Llewellyn

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Isosteric Heat ◽

Material Characterisation ◽

Mixture Adsorption ◽

Surface Energetics ◽

Adsorption Processing ◽

User Friendly

Material characterisation through adsorption is a widely-used laboratory technique. The isotherms obtained through volumetric or gravimetric experiments impart insight through their features but can also be analysed to determine material characteristics such as specific surface area, pore size distribution, surface energetics, or used for predicting mixture adsorption. The pyGAPS (python General Adsorption Processing Suite) framework was developed to address the need for high-throughput processing of such adsorption data, independent of the origin, while also being capable of presenting individual results in a user-friendly manner. It contains many common characterisation methods such as: BET and Langmuir surface area, t and α plots, pore size distribution calculations (BJH, Dollimore-Heal, Horvath-Kawazoe, DFT/NLDFT kernel fitting), isosteric heat calculations, IAST calculations, isotherm modelling and more, as well as the ability to import and store data from Excel, CSV, JSON and sqlite databases. In this work, a description of the capabilities of pyGAPS is presented. The code is then be used in two case studies: a routine characterisation of a UiO-66(Zr) sample and in the processing of an adsorption dataset of a commercial carbon (Takeda 5A) for applications in gas separation.

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Air filtration improvement of konjac glucomannan-based aerogel air filters through physical structure design

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctab011 ◽

2021 ◽

Author(s):

Hong Qian ◽

Ying Fang ◽

Kao Wu ◽

Hao Wang ◽

Bin Li ◽

...

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Physical Structure ◽

Structure Design ◽

Air Filtration ◽

Air Filters ◽

Air Filter ◽

Purification Time

Abstract This study presents two methods to improve the air filtration performance of konjac glucomannan (KGM)-based aerogel air filters through physical structure design by changing the pore-size distribution and the surface area, using an air purifier. Results indicated that KGM-based aerogels had a comparable filtration effect with the commercial air filter with a longer purification time. This purification time could be shortened by over 50%, by changing the pore-size distribution from large size to small size or increase the surface area with the fold structure. This should boost the development of polysaccharide-based aerogel used as the air filter.

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Study of deactivation in mesocellular foam carbon (MCF-C) catalyst used in gas-phase dehydrogenation of ethanol

Scientific Reports ◽

10.1038/s41598-021-91190-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoottapong Klinthongchai ◽

Seeroong Prichanont ◽

Piyasan Praserthdam ◽

Bunjerd Jongsomjit

Keyword(s):

Catalytic Activity ◽

Pore Size ◽

Gas Phase ◽

Surface Area ◽

Active Sites ◽

Operating Temperature ◽

Coke Formation ◽

Ethanol Conversion ◽

Deactivation Of Catalyst ◽

Dehydrogenation Of Ethanol

AbstractMesocellular foam carbon (MCF-C) is one the captivating materials for using in gas phase dehydrogenation of ethanol. Extraordinary, enlarge pore size, high surface area, high acidity, and spherical shape with interconnected pore for high diffusion. In contrary, the occurrence of the coke is a majority causes for inhibiting the active sites on catalyst surface. Thus, this study aims to investigate the occurrence of the coke to optimize the higher catalytic activity, and also to avoid the coke formation. The MCF-C was synthesized and investigated using various techniques. MCF-C was spent in gas-phase dehydrogenation of ethanol under mild conditions. The deactivation of catalyst was investigated toward different conditions. Effects of reaction condition including different reaction temperatures of 300, 350, and 400 °C on the deactivation behaviors were determined. The results indicated that the operating temperature at 400 °C significantly retained the lowest change of ethanol conversion, which favored in the higher temperature. After running reaction, the physical properties as pore size, surface area, and pore volume of spent catalysts were decreased owing to the coke formation, which possibly blocked the pore that directly affected to the difficult diffusion of reactant and caused to be lower in catalytic activity. Furthermore, a slight decrease in either acidity or basicity was observed owing to consumption of reactant at surface of catalyst or chemical change on surface caused by coke formation. Therefore, it can remarkably choose the suitable operating temperature to avoid deactivation of catalyst, and then optimize the ethanol conversion or yield of acetaldehyde.

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Effect of Air Oxidation on Texture, Surface Properties and Dye Adsorption of Wood-Derived Porous Carbon Materials

Materials ◽

10.3390/ma12101675 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1675 ◽

Cited By ~ 1

Author(s):

Suhong Ren ◽

Liping Deng ◽

Bo Zhang ◽

Yafang Lei ◽

Haiqing Ren ◽

...

Keyword(s):

Surface Area ◽

Functional Groups ◽

Porous Carbon ◽

Carbon Materials ◽

Dye Adsorption ◽

Carbon Surface ◽

Air Oxidation ◽

Activation Temperature ◽

Porous Carbon Materials ◽

Hierarchical Porous

Hierarchical porous carbon materials made from cork were fabricated using a facile and green method combined with air activation, without any templates and chemical agents. The influence of air activation on the texture and other surface characteristics of the carbon materials were evaluated by various characterization techniques. Results indicate that air oxidation can effectively improve the surface area and the hierarchical porous structure of carbon materials, as well as increase the number of oxygen-containing functional groups on the carbon surface. The specific surface area and the pore volume of the carbon material activated by air at 450 °C (C800-M450) can reach 580 m2/g and 0.379 cm3/g, respectively. These values are considerably higher than those for the non-activated material (C800, 376 m2/g, 0.201 cm3/g). The contents of the functional groups (C–O, C=O and O–H) increased with rising activation temperature. After air activation, the adsorption capacity of the carbon materials for methylene blue (MB) and methyl orange (MO) was increased from 7.7 and 6.4 mg/g for C800 to 312.5 and 97.1 mg/g for C800-M450, respectively. The excellent dye removal of the materials suggests that the porous carbon obtained from biomass can be potentially used for wastewater treatment.

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