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Yildiz H, Gülşen H, Şahin Ö, Baytar O, Kutluay S. Novel adsorbent for malachite green from okra stalks waste: synthesis, kinetics and equilibrium studies. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2024; 26:369-381. [PMID: 37551855 DOI: 10.1080/15226514.2023.2243621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
In this study, malachite green (MG) removal was performed with activated carbon synthesized from okra stalks by microwave assisted chemical activation method. In the synthesis of activated carbon, the effects of gas in the microwave, activation, and impregnation rate were investigated. The synthesized activated carbon characterization was investigated using BET, FT-IR, and SEM analyses. The activated carbon surface area achieved was 759.453 m2 g-1. In addition, the surface area of activated carbon synthesized using the conventional method was17.766 m2 g-1. The effect of the initial solution concentration on MG adsorption was investigated. According to the kinetic and equilibrium data, it was found that the adsorption process best fitted the pseudo-second order kinetic model and the Langmuir isotherm. According to the equilibrium data, the maximum adsorption capacity (qmax) of the monolayer was 119.05 mg g-1. In addition, MG adsorption was investigated by the experimental design method. The adsorption capacity at the determined optimum conditions was 99.63 mg g-1. All results show that activated carbon synthesized from waste biomass by combining the conventional method with microwave-assisted impregnation is a cheap and environmentally friendly adsorbent.
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Affiliation(s)
- Hakan Yildiz
- Department of Environmental Technologies, Harran University, Sanlıurfa, Türkiye
| | - Hakki Gülşen
- Department of Environmental Engineering, Harran University, Sanlıurfa, Türkiye
| | - Ömer Şahin
- Department of Chemical Engineering, Istanbul Technical University, İstanbul, Türkiye
| | - Orhan Baytar
- Department of Chemical Engineering, Siirt University, Siirt, Türkiye
| | - Sinan Kutluay
- Department of Chemical Engineering, Istanbul Technical University, İstanbul, Türkiye
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Zhang X, Luo S, Duan J, Lan T, Wei Y. Fabrication of sodium alginate-doped carbon dot composite hydrogel and its application for La (III) adsorption and enhanced the removal of phosphorus. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:108230-108246. [PMID: 37749475 DOI: 10.1007/s11356-023-29958-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023]
Abstract
Adsorption is an effective method for the removal of hazardous substances from wastewater. In this work, a low-cost and environmental-friendly composite hydrogel material of sodium alginate doped with nitrogen doped carbon dots (SA@NCDs) was fabricated by impregnation for lanthanide and enhanced phosphorus adsorption in wastewater. The effects of NCDs doping amount, dosage, pH, initial solution concentration, adsorption time and temperature on the process of La (III) adsorption by SA@NCDs were investigated. The adsorption isotherms fitted to Langmuir isotherm model (R2 = 0.9970-0.9989) and the adsorption kinetics followed pseudo-second-order kinetic model (R2 = 0.9992). The maximum adsorption capacity of the adsorbent for La (III) was 217.39 mg/g according to the Langmuir model at 298.15 K. After five cycles, the removal efficiency of La (III) adsorbed by SA@NCDs was still 85.1%. Moreover, the loaded La (III) enhanced the adsorption of phosphorus. The La (III)-SA@NCDs-5 hydrogel adsorbent greatly improved the adsorption capacity for phosphorus compared with the La (III)-free adsorbent, and the adsorption amount can reach 9.64 mg-P/g. The SA@NCDs complex hydrogels for rare earth adsorption were prepared by introducing NCDs rich in amino group into SA hydrogels. The introduction of NCDs increases the adsorption sites of hydrogels, and also overcomes the problem that NCDs itself is difficult to recover in wastewater treatment applications. The lanthanide adsorbed material has a stable structure and can be used to remove phosphorus to deal with waste using the waste. It indicates the SA@NCDs hydrogel composite adsorbent have good potential for wastewater treatment.
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Affiliation(s)
- Xiao Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 3rdRing North East Road, Chaoyang District, Beijing, 100029, China
| | - Shiwen Luo
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 3rdRing North East Road, Chaoyang District, Beijing, 100029, China
| | - Jiaxin Duan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 3rdRing North East Road, Chaoyang District, Beijing, 100029, China
| | - Tao Lan
- China National Institute of Standardization, Zhong Guancun South Avenue, Haidian District, Beijing, 100081, China
| | - Yun Wei
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 3rdRing North East Road, Chaoyang District, Beijing, 100029, China.
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Kumar DP, Ramesh D, Vikraman VK, Subramanian P. Synthesis of carbon molecular sieves from agricultural residues: Status, challenges and prospects. ENVIRONMENTAL RESEARCH 2022; 214:114022. [PMID: 35977589 DOI: 10.1016/j.envres.2022.114022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/26/2022] [Accepted: 07/29/2022] [Indexed: 06/15/2023]
Abstract
Adsorption is the most promising technology used in the gas separation and purification process. The key success of this technology relies on the selection of an adsorbent. Activated carbon and zeolites are the most commonly used adsorbents in the separation of particular gas from gaseous mixtures. Activated carbon deriving from fossil and biomass-based resources has wide pore size distribution and thereby results in lower selectivity. Whereas, zeolites synthesized from natural minerals are expensive which increases the cost of the purification process. Taking this into concern, the quest for synthesizing low-cost and effective adsorbents has gained greater attention in recent years. Carbon Molecular Sieves (CMSs), are considered as an attractive alternative to replace the conventional adsorbents. Furthermore, CMSs exhibit higher selectivity and adsorption capacity, due to their narrow micropore size distribution (0.3-0.5 nm). CMSs are synthesized from any organic carbonaceous precursor with low inorganic content. Since most of the agricultural residues fall under this category, they can be used as a feedstock for CMSs production. The synthesis of CMSs involves three stages: carbonization, activation, and pore modification. In this review, physicochemical characteristics of various agricultural residues, the effects of carbonization process parameters, activation methods, and pore modification techniques adopted for producing CMSs are comprehensively discussed. The effect of deposition temperature, time, and flow rate of depositing agent on pore characteristics of CMSs is briefed. The prospects and challenges in CMSs production are also studied. The insights in this review provide guidelines for synthesizing CMSs from agro-residues.
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Affiliation(s)
- D Praveen Kumar
- Department of Renewable Energy Engineering, Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, 641003, India
| | - D Ramesh
- Department of Renewable Energy Engineering, Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, 641003, India.
| | - V Karuppasamy Vikraman
- Department of Renewable Energy Engineering, Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, 641003, India
| | - P Subramanian
- Department of Renewable Energy Engineering, Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, 641003, India
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Memetova A, Tyagi I, Singh L, Karri RR, Tyagi K, Kumar V, Memetov N, Zelenin A, Tkachev A, Bogoslovskiy V, Shigabaeva G, Galunin E, Mubarak NM, Agarwal S. Nanoporous carbon materials as a sustainable alternative for the remediation of toxic impurities and environmental contaminants: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155943. [PMID: 35577088 DOI: 10.1016/j.scitotenv.2022.155943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/10/2022] [Accepted: 05/10/2022] [Indexed: 06/15/2023]
Abstract
Due to rapidly deteriorating water resources, the world is looking forward to a sustainable alternative for the remediation of noxious pollutants such as heavy metals and organic and gaseous contaminants. To address this global issue of environmental pollution, nanoporous carbon materials (NPCMs) can be used as a one-stop solution. They are widely applied as adsorbents for many toxic impurities and environmental contaminants. The present review provides a detailed overview of the role of different synthesis factors on the porous characteristics of carbon materials, activating agents, reagent-precursor ratio and their potential application in the remediation. Findings revealed that synthetic parameters result in the formation of microporous NPCMs (SBET: >4000 m3/g; VTotal (cm3/g) ≥ 2; VMicro (cm3/g) ≥ 1), micromesoporous (SBET: >2500 m3/g; VTotal (cm3/g) ≥ 1.5; VMicro (cm3/g) ≥ 0.7) and mesoporous (SBET: >2500 m3/g; VTotal (cm3/g) ≥ 1.5; VMicro (cm3/g) ≥ 0.5) NPCMs. Moreover, it was observed that a narrow pore size distribution (0.5-2.0 nm) yields excellent results in the remediation of noxious contaminants. Further, chemical activating agents such as NaOH, KOH, ZnCl2, and H3PO4 were compared. It was observed that activating agents KОН, H3PO4, and ZnCl2 were generally used and played a significant role in the possible large-scale production and commercialization of NPCMs. Thus, it can be interpreted that with a well-planned strategy for the synthesis, NPCMs with a "tuned" porosity for a specific application, in particular, microporosity for the accumulation and adsorption of energetically important gases (CO2, CH4, H2), micro-mesoporosity and mesoporosity for high adsorption capacity for towards metal ions and a large number of dyes, respectively.
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Affiliation(s)
- Anastasia Memetova
- Department of Technology and Methods of Nanoproducts Manufacturing, Tambov State Technical University, 106 Sovetskaya St., Tambov 392000, Russian Federation
| | - Inderjeet Tyagi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata 700 053, India.
| | - Lipi Singh
- Department of Environmental Engineering, Delhi Technological University, New Delhi 110042, India
| | - Rama Rao Karri
- Petroleum and Chemical Engineering, Faculty of Engineering, Universiti Teknologi Brunei, Bandar Seri Begawan BE1410, Brunei Darussalam
| | - Kaomud Tyagi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata 700 053, India
| | - Vikas Kumar
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata 700 053, India
| | - Nariman Memetov
- Department of Technology and Methods of Nanoproducts Manufacturing, Tambov State Technical University, 106 Sovetskaya St., Tambov 392000, Russian Federation
| | - Andrey Zelenin
- Department of Technology and Methods of Nanoproducts Manufacturing, Tambov State Technical University, 106 Sovetskaya St., Tambov 392000, Russian Federation
| | - Alexey Tkachev
- Department of Technology and Methods of Nanoproducts Manufacturing, Tambov State Technical University, 106 Sovetskaya St., Tambov 392000, Russian Federation
| | - Vladimir Bogoslovskiy
- Research School of Chemistry & Applied Biomedical Sciences, Tomsk Polytechnic University, 30 Lenina Ave., Tomsk 634050, Russian Federation
| | - Gulnara Shigabaeva
- Department of Organic and Ecological Chemistry, University of Tyumen, 6 Volodarskogo St., Tyumen 625003, Russian Federation
| | - Evgeny Galunin
- Department of Organic and Ecological Chemistry, University of Tyumen, 6 Volodarskogo St., Tyumen 625003, Russian Federation
| | - Nabisab Mujawar Mubarak
- Petroleum and Chemical Engineering, Faculty of Engineering, Universiti Teknologi Brunei, Bandar Seri Begawan BE1410, Brunei Darussalam
| | - Shilpi Agarwal
- Center for Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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Nano-Structured Carbon: Its Synthesis from Renewable Agricultural Sources and Important Applications. MATERIALS 2022; 15:ma15113969. [PMID: 35683277 PMCID: PMC9182223 DOI: 10.3390/ma15113969] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/24/2022] [Accepted: 05/30/2022] [Indexed: 11/24/2022]
Abstract
Carbon materials are versatile in nature due to their unique and modifiable surface and ease of production. Nanostructured carbon materials are gaining importance due to their high surface area for application in the energy, biotechnology, biomedical, and environmental fields. According to their structures, carbon allotropes are classified as carbon nanodots, carbon nanoparticles, graphene, oxide, carbon nanotubes, and fullerenes. They are synthesized via several methods, including pyrolysis, microwave method, hydrothermal synthesis, and chemical vapor deposition, and the use of renewable and cheaper agricultural feedstocks and reactants is increasing for reducing cost and simplifying production. This review explores the nanostructured carbon detailed investigation of sources and their relevant reports. Many of the renewable sources are covered as focused here, such as sugar cane waste, pineapple, its solid biomass, rise husk, date palm, nicotine tabacum stems, lapsi seed stone, rubber-seed shell, coconut shell, and orange peels. The main focus of this work is on the various methods used to synthesize these carbon materials from agricultural waste materials, and their important applications for energy storage devices, optoelectronics, biosensors, and polymer coatings.
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Saka C, Yardim Y, Şahin Ö, Baytar O. Iodine adsorption and electrochemical double-layer capacitor characteristics of activated carbon prepared from low-cost biomass. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2022; 25:74-81. [PMID: 35385347 DOI: 10.1080/15226514.2022.2057420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The efficient adsorption application and electric double-layer capacitor material with low-cost biomass-based activated carbon materials have been quite common recently. In this study, chestnut shell-based activated carbons were produced by chemical activation. ZnCl2, H3PO4, and KOH agents were used for chemical activation. The obtained activated carbon, iodine adsorption from aqueous solutions, and its use as an electro capacitor were investigated. The scanning electron microscope, nitrogen adsorption/desorption, and Fourier transform infrared spectroscopy were used for characterization. The values of surface area and iodine adsorption capacity of the chestnut shell-based activated carbon are 1544 m2 g-1 and 1525 mg g-1. As a result, a specific capacitance of 97 Fg-1 with chestnut shell-based activated carbon was obtained in a 1 M KCl electrolyte for the electrochemical double-layer capacitor. This study shows that activated carbon based on the chestnut shell can be used both as an electrochemical energy storage material and as an adsorbent in iodine adsorption.
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Affiliation(s)
- Cafer Saka
- Faculty of Health Sciences, Siirt University, Siirt, Turkey
| | - Yavuz Yardim
- Faculty of Pharmacy, Van Yuzuncu Yil University, Van, Turkey
| | - Ömer Şahin
- Faculty of Engineering, Siirt University, Siirt, Turkey
| | - Orhan Baytar
- Faculty of Engineering, Siirt University, Siirt, Turkey
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Hou L, Chen L, Song P, Zhang Y, Wang X. Comparative assessment of the effect of pretreatment with microwave and roast heating on the quality of black sesame pastes. J Food Sci 2021; 86:5353-5374. [PMID: 34888858 DOI: 10.1111/1750-3841.15976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/12/2021] [Accepted: 10/19/2021] [Indexed: 01/13/2023]
Abstract
Heating is a key procedure in producing sesame paste. The effects of microwave heating and conventional roasting on the physicochemical features, protein profiles, and volatile compounds of black sesame pastes made of black sesame seeds from Burma and China were evaluated in this study. All heating treatments decreased the moisture contents of black sesame pastes, and roasting yielded lower moisture levels, although with similar chroma (p < 0.05). The samples subjected to microwave heating had remarkably lower peroxide values than those heated with roasting (p < 0.05). Chinese microwave-heated samples had a higher nitrogen solubility index than roasting (p < 0.05). Both microwave and roasting increased the contents of the volatiles notably. SDS-PAGE showed that the intensity of the 2-15 kDa band decreased markedly after heating and nearly diminished for roasting samples, suggesting that roasting was more remarkable for the promotion to the protein aggregation. The results indicated that the quality traits of black sesame paste not only depend on the heating methods, but also the heating power/temperature and duration, and the source of the materials.
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Affiliation(s)
- Lixia Hou
- College of Food Science and Technology, Henan University of Technology, Zhengzhou, China
| | - Liyan Chen
- College of Food Science and Technology, Henan University of Technology, Zhengzhou, China
| | - Pinqing Song
- College of Food Science and Technology, Henan University of Technology, Zhengzhou, China
| | - Yujin Zhang
- College of Food Science and Technology, Henan University of Technology, Zhengzhou, China
| | - Xuede Wang
- College of Food Science and Technology, Henan University of Technology, Zhengzhou, China
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Costa RLT, do Nascimento RA, de Araújo RCS, Vieira MGA, da Silva MGC, de Carvalho SML, de Faria LJG. Removal of non-steroidal anti-inflammatory drugs (NSAIDs) from water with activated carbons synthetized from waste murumuru (Astrocaryum murumuru Mart.): Characterization and adsorption studies. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116980] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Batur E, Baytar O, Kutluay S, Horoz S, Şahin Ö. A comprehensive new study on the removal of Pb (II) from aqueous solution by şırnak coal-derived char. ENVIRONMENTAL TECHNOLOGY 2021; 42:505-520. [PMID: 32804581 DOI: 10.1080/09593330.2020.1811397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
In this study, char was prepared from the Şırnak coal derivative as a new adsorbent by the pyrolysis process and successfully applied for Pb (II) removal. Prepared char adsorbent was characterized by analysis techniques such as thermogravimetric (TG)/differential thermogravimetric (DTG), iodine number, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) surface area. In the experimental design of the Pb (II) removal process, the relationship between operating factors (contact time, initial Pb (II) concentration and temperature) and process responses (adsorption capacity and removal efficiency) was modelled by applying response surface methodology (RSM). After that, the operating factors for the maximum adsorption capacity and removal efficiency of Pb (II) by char were optimized. In the removal of Pb (II), pseudo-first order and pseudo-second order kinetic models were used to determine the process mechanism. In addition, adsorption isotherm models such as Langmuir, Freundlich, and Dubinin-Radushkevich were applied to the equilibrium data to explain the adsorption mechanism between the adsorbent and adsorbate molecules. According to the results obtained, it was determined that kinetic and equilibrium isotherm data were better defined with pseudo-second order kinetic and Dubinin-Radushkevich isotherm models, respectively. The optimum values of the contact time, initial Pb (II) concentration, and temperature for maximum adsorption capacity (124.64 mg/g) and removal efficiency (92.35%) of Pb (II) were found as 150.00 min, 144.81 ppm, and 35.06°C, respectively. This study indicated the application potential of Şırnak coal-derived char as a promising cost-effective adsorbent for the removal of heavy metals.
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Affiliation(s)
- Ebru Batur
- Department of Chemical Engineering, Siirt University, Siirt, Turkey
| | - Orhan Baytar
- Department of Chemical Engineering, Siirt University, Siirt, Turkey
| | - Sinan Kutluay
- Department of Chemical Engineering, Siirt University, Siirt, Turkey
| | - Sabit Horoz
- Department of Electrical &Electronics Engineering, Siirt University, Siirt, Turkey
| | - Ömer Şahin
- Department of Chemical Engineering, Siirt University, Siirt, Turkey
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Bashiri H, Nesari S, Sarabadan M. Microwave assistant production of a high performance adsorbent from rice husk. KOREAN J CHEM ENG 2020. [DOI: 10.1007/s11814-019-0446-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Aslan Y, Sharif YM, Şahin Ö. Covalent immobilization of Aspergillus niger amyloglucosidase (ANAG) with ethylenediamine-functionalized and glutaraldehyde-activated active carbon (EFGAAC) obtained from sesame seed shell. Int J Biol Macromol 2020; 142:222-231. [DOI: 10.1016/j.ijbiomac.2019.09.226] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 09/22/2019] [Accepted: 09/24/2019] [Indexed: 01/06/2023]
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The Pertinence of Microwave Irradiated Coconut Shell Bio-Sorbent for Wastewater Decolourization: Structural Morphology and Adsorption Optimization Using the Response Surface Method (RSM). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15102200. [PMID: 30304814 PMCID: PMC6209996 DOI: 10.3390/ijerph15102200] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/02/2018] [Accepted: 10/04/2018] [Indexed: 11/30/2022]
Abstract
Palm oil mill effluent contains carcinogenic coloured compounds that are difficult to separate due to their aromatic structure. Though colour treatment using adsorption processes at lower pH (<4) have been reported effectual, due to its acidity the remediated effluent poses an environmental hazard as a result. Thus, the current study focused on achieving decolourization at neutral pH by enhancing the morphology of the coconut shell activated carbon (CSAC) using N2 as activating-agent with microwave irradiation heating. The microwave pretreated and non-pretreated CSAC were characterized using scanned electron microscopy (SEM), energy dispersive X-ray (EDX) and Brunauer-Emmett-Teller (BET) analysis. A significant modification in the porous structure with a 66.62% increase in the specific surface area was achieved after the pretreatment. The adsorption experimental matrix was developed using the central composite design to investigate the colour adsorption performance under varied pH (6–7), dosage (2–6 g) and contact time (10–100 min). At optimum conditions of neutral pH (7), 3.208 g dosage and contact time of 35 min, the percentage of colour removal was 96.29% with negligible differences compared with the predicted value, 95.855%. The adsorption equilibrium capacity of 1430.1 ADMI × mL/g was attained at the initial colour concentration of 2025 ADMI at 27 °C. The experimental data fitted better with the Freundlich isotherm model with R2 0.9851.
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