Activated carbon prepared from coffee pulp: potential adsorbent of organic contaminants in aqueous solution

The processing of coffee beans generates large amounts of solid and liquid residues. The solid residues (pulp, husk and parchment) represent a serious environmental problem and do not have an adequate disposal mechanism. In this work, activated carbons (ACs) for adsorption of organic compounds were prepared from coffee pulp by controlled temperature at different pulp/Na2HPO4 ratios (4:1, 2:1, 5:4 and 1:1). The N2 adsorption/desorption isotherms showed ACs with high quantities of mesopores and micropores and specific surface areas of 140, 150, 450 and 440 m2g−1 for AC 4:1, AC 2:1, AC 5:4 and AC 1:1, respectively. The prepared material AC 5:4 showed a higher removal capacity of the organic contaminants methylene blue (MB), direct red (DR) and phenol than did a Merck AC. The maximum capacities for this AC are approximately 150, 120 and 120 mg g−1 for MB, DR and phenol, respectively. Thus, a good adsorbent was obtained from coffee pulp, an abundant Brazilian residue.

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Effect of ZnCl2 impregnation ratio on pore structure of activated carbons prepared from cattle manure compost: application of N2 adsorption-desorption isotherms

Journal of Material Cycles and Waste Management ◽

10.1007/s10163-007-0185-x ◽

2008 ◽

Vol 10 (1) ◽

pp. 53-61 ◽

Cited By ~ 11

Author(s):

Qingrong Qian ◽

Motoi Machida ◽

Masami Aikawa ◽

Hideki Tatsumoto

Keyword(s):

Pore Structure ◽

Activated Carbons ◽

Cattle Manure ◽

N2 Adsorption ◽

Manure Compost ◽

Impregnation Ratio ◽

Compost Application ◽

Desorption Isotherms ◽

Cattle Manure Compost ◽

Adsorption Desorption

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Preparation and Application of Biochars for Organic and Microbial Control in Wastewater Treatment Regimes

Advanced Treatment Techniques for Industrial Wastewater - Advances in Environmental Engineering and Green Technologies ◽

10.4018/978-1-5225-5754-8.ch002 ◽

2019 ◽

pp. 19-34 ◽

Cited By ~ 1

Author(s):

Victor Odhiambo Shikuku ◽

Wilfrida N. Nyairo ◽

Chrispin O. Kowenje

Keyword(s):

Organic Pollutants ◽

Organic Contaminants ◽

Activated Carbons ◽

Low Cost ◽

Microbial Control ◽

Chemical Compositions ◽

Preparation Methods ◽

Factors Affecting ◽

Surface Areas ◽

Control Factors

Biochars have been extensively applied in soil remediation, carbon sequestration, and in climate change mitigation. However, in recent years, there has been a significant increase in biochar research in water treatment due to their stupendous adsorptive properties for various contaminants. This is attributed to their large surface areas, pore structures, chemical compositions, and low capital costs involved making them suitable candidates for replacing activated carbons. This chapter discusses the preparation methods and properties of biochars and their removal efficacy for organic contaminants and microbial control. Factors affecting adsorption and the mechanisms of adsorption of organic pollutants on biochars are also concisely discussed. Biochars present environmentally benign and low-cost adsorbents for removal of both organic pollutants and microbial control for wastewater purification systems.

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Utilization of spent dregs for the production of activated carbon for CO2 adsorption

Polish Journal of Chemical Technology ◽

10.1515/pjct-2017-0026 ◽

2017 ◽

Vol 19 (2) ◽

pp. 44-50 ◽

Cited By ~ 1

Author(s):

Jarosław Serafin

Keyword(s):

Carbon Dioxide ◽

Activated Carbon ◽

Density Functional ◽

Activated Carbons ◽

Density Functional Theory Method ◽

Textural Properties ◽

Carbon Dioxide Adsorption ◽

Functional Theory ◽

Surface Areas ◽

Adsorption Desorption

Abstract The objective of this work was preparation of activated carbon from spent dregs for carbon dioxide adsorption. A saturated solution of KOH was used as an activating agent. Samples were carbonized in the furnace at the temperature of 550°C. Textural properties of activated carbons were obtained based on the adsorption-desorption isotherms of nitrogen at −196°C and carbon dioxide at 0°C. The specific surface areas of activated carbons were calculated by the Brunauer – Emmett – Teller equation. The volumes of micropores were obtained by density functional theory method. The highest CO2 adsorption was 9.54 mmol/cm3 at 0°C – and 8.50 mmol/cm3 at 25°C.

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Simultaneous activation/sulfurization method for production of sulfurized activated carbons: characterization and Hg(II) adsorption capacity

Water Science & Technology ◽

10.2166/wst.2013.741 ◽

2013 ◽

Vol 69 (3) ◽

pp. 546-552 ◽

Cited By ~ 7

Author(s):

Hadi ShamsiJazeyi ◽

Tahereh Kaghazchi

Keyword(s):

Specific Surface ◽

Adsorption Capacity ◽

Activated Carbons ◽

Nitrogen Adsorption ◽

Surface Charges ◽

Ph Values ◽

Surface Areas ◽

Simultaneous Activation ◽

Adsorption Desorption ◽

Significant Attention

As an inexpensive method for modification of activated carbons (ACs), sulfurization has attracted significant attention. However, the resulting sulfurized activated carbons (SACs) often are less porous than the original ACs. In this work, we propose a new method for concurrent sulfurization/activation that can lead to preparation of SACs with more porosity than the corresponding non-sulfurized ACs. By using scanning electron microscopy, nitrogen adsorption/desorption, and iodine number experiments, the porous structure of the SACs has been compared with that of non-sulfurized ACs. The specific surface areas of SACs are higher than the corresponding ACs, regardless of the type of activation agents used. For instance, the specific surface area of SAC and AC activated with phosphoric acid is 1,637 and 1,338 m2/g, respectively. Additionally, sulfur contents and surface charges (pHpzc) of the SACs and non-sulfurized ACs are compared. In fact, the SACs have higher sulfur contents and more acidic surfaces. Furthermore, the Hg(II) adsorption capacity of SACs has been compared with the corresponding non-sulfurized ACs. The Hg(II) adsorption isotherms on a selected SAC is measured at different pH values and temperatures. Hg(II) adsorptions as high as 293 mg/g are observed by using SACs prepared by the method proposed in this study.

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Characterization of Chemically Activated Carbons Prepared from Miscanthus and Switchgrass Biomass

Materials ◽

10.3390/ma13071654 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1654 ◽

Cited By ~ 2

Author(s):

Beata Doczekalska ◽

Monika Bartkowiak ◽

Bogusława Waliszewska ◽

Grażyna Orszulak ◽

Joanna Cerazy-Waliszewska ◽

...

Keyword(s):

Activated Carbons ◽

Nitrogen Adsorption ◽

Crop Species ◽

Alternative Source ◽

Surface Oxygen Groups ◽

Surface Areas ◽

Oxygen Groups ◽

Adsorption Desorption ◽

Chemical Groups

Lignocellulosic biomass, including that of energy crops, can be an alternative source to produce activated carbons (ACs). Miscanthus and switchgrass straw were used to produce ACs in a two-step process. Crushed plant material was carbonized at 600 °C and then obtained carbon was activated using NaOH or KOH at 750 °C. The content of surface oxygen groups was determined using Boehm’s method. The porosity of ACs was assayed using the nitrogen adsorption/desorption technique, while their thermal resistance using the thermogravimetric method. The ACs derived from miscanthus and switchgrass were characterized by surfaces rich in chemical groups and a highly developed porous structure. The highest specific surface areas, over 1600 m2/g, were obtained after carbon treatment with NaOH. High values of iodine number, 1200–1240 mg/g, indicate an extensive system of micropores and their good adsorption properties. The type of activator affected the contents of oxygen functional groups and some porosity parameters as well as thermal stability ranges of the ACs. Among obtained carbons, the highest quality was found for these derived from M. sacchariflorus followed by switchgrass, after activation with NaOH. Hence, while these crop species are not as effective biomass sources as other energy grasses, they can become valuable feedstocks for ACs.

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Removal of organic phosphorus and formaldehyde in glyphosate wastewater by CWO and the lime-catalyzed formose reaction

Water Science & Technology ◽

10.2166/wst.2017.006 ◽

2017 ◽

Vol 75 (6) ◽

pp. 1390-1398 ◽

Cited By ~ 5

Author(s):

Bo Xing ◽

Honglin Chen ◽

Xiaoming Zhang

Keyword(s):

Biological Treatment ◽

Activated Carbons ◽

Organic Phosphorus ◽

Treatment Method ◽

Catalytic Wet Oxidation ◽

N2 Adsorption ◽

Formose Reaction ◽

H2o2 Oxidation ◽

Adsorption Desorption ◽

Autoclave Reactor

Glyphosate (PMG) wastewater with 40–600 mg/L organic phosphorus (OP) and 1–4% CH2O was treated by catalytic wet oxidation (CWO) and the lime-catalyzed formose reaction to remove total phosphorus (TP) and improve biodegradability. Activated carbons (ACs) modified by H2O2 oxidation and thermal treatment with melamine were used as CWO catalysts and characterized by N2 adsorption/desorption and XPS. The CWO experiments were performed in an autoclave reactor at 110–130 °C and 1.0 MPa. The modified AC showed higher catalytic activity than the parent AC due to the introduction of nitrogen-containing functional groups, exhibited over 90% OP removal for various real PMG wastewaters, and had good stability for 20 consecutive CWO runs. The CWO effluents were further treated by lime at 80 °C to remove TP and CH2O. The treated efﬂuents, containing 0.5–12 mg/L TP and 20–60 mg/L CH2O, showed good biodegradability with a BOD5/COD ratio of 0.31–0.41. The combination of CWO and lime is an effective treatment method prior to biological treatment for solving the problems of OP and CH2O encountered by the glyphosate industry.

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Ultrasound-Assisted Hydrothermal Fabrication of AgI/MFeO3/g-C3N4 (M = Y, Gd, La) Nano Sheet–Sphere–Sheet Photocatalysts with Enhanced Photodegradation Activities for Norfloxacin

Catalysts ◽

10.3390/catal10040373 ◽

2020 ◽

Vol 10 (4) ◽

pp. 373

Author(s):

Junjiao Zhang ◽

Zhengru Zhu ◽

Junchao Jiang ◽

Hong Li

Keyword(s):

Optical Absorption ◽

Organic Contaminants ◽

Photocatalytic Performance ◽

Absorption Capacity ◽

N2 Adsorption ◽

Photogenerated Electrons ◽

Ultrasound Assisted ◽

Desorption Isotherms ◽

Hydrothermal Approach ◽

Adsorption Desorption

AgI/MFeO3/g-C3N4 (M = Y, Gd, La) nano sheet–sphere–sheet photocatalysts were synthesized by a simple ultrasound-assisted hydrothermal approach. We characterized the microstructure, surface morphology, and optical absorption capacity of the obtained samples. According to the characterization results, AgI/MFeO3/g-C3N4 (M = Y, Gd, La) nano sheet–sphere–sheet photocatalysts were successfully obtained. MFeO3 nanospheres and AgI nanosheets were dispersed evenly on the surface of g-C3N4 nanosheets. AgI/MFeO3/g-C3N4 showed remarkable photocatalytic. Especially, 95% of NOF was photodegradated over AgI/LaFeO3/g-C3N4 within 3 h and the higher photocatalytic performance still remained after six cycles. Additionally, The N2 adsorption–desorption isotherms of AgI/MFeO3/g-C3N4 showed that AgI/LaFeO3/g-C3N4 possessed the highest specific surface area (79.32 m2/g). The result of scavenging experiment revealed that ·O2−, h+, and ·OH were the main roles in the photodegradation process. Benefitting from the nice energy band matching, MFeO3 acted as the center of photogenerated electrons migration and separation provided more direct electron channels. This work proposes an effective approach for the design and configuration of dual Z-scheme photocatalysts to accomplish the removal of organic contaminants based on g-C3N4.

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