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Kumar V, Verma P. Microbial valorization of kraft black liquor for production of platform chemicals, biofuels, and value-added products: A critical review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121631. [PMID: 38986370 DOI: 10.1016/j.jenvman.2024.121631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 06/10/2024] [Accepted: 06/26/2024] [Indexed: 07/12/2024]
Abstract
The proper treatment and utilization of kraft black liquor, generated from the pulp and paper industry through the kraft pulping method, is required to reduce environmental impacts prior to the final disposal. It also improves the economic performance through the utilization of waste. Microbial valorization appears to demonstrates the dual benefits of waste management and resource recovery by providing an innovative solution to convert kraft black liquor into resource for reuse. A comprehensive review on the microbial valorization of kraft black liquor, describing the role in valorization and management, is still lacking in the literature, forming the rationale of this article. Thus, the present study reviews and systematically discusses the potential of utilizing microorganisms to valorize kraft black liquor as a sustainable feedstock to develop a numerous portfolio of platform chemicals, bioenergy, and other value-added products. This work contributes to sustainability and resource efficiency within the pulp and paper industry. The recent developments in utilization of synthetic biology tools and molecular techniques, including omics approaches for engineering novel microbial strains, for enhancing kraft black liquor valorization has been presented. This review explores how the better utilization of kraft black liquor in the pulp and paper industry contributes to achieving UN Sustainable Development Goals (SDGs), particularly clean water and sanitation (SDG 6) as well as the affordable and clean energy goal (SDG 7). The current review also addresses challenges related to toxicity, impurities, low productivity, and downstream processing that serve as obstacles to the progress of developing highly efficient bioproducts. The new directions for future research efforts to fill the critical knowledge gaps are proposed. This study concludes that by implementing microbial valorization techniques, the pulp and paper industry can transition from a linear to a circular bioeconomy and eco-friendly manage the kraft black liuor. This approach showed to be effective towards resource recovery, while simultaneously minimizing the environmental burden.
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Affiliation(s)
- Vineet Kumar
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Pradeep Verma
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India.
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Gupta GK, Kapoor RK. Recent advances in eco-friendly technology for decontamination of pulp and paper mill industrial effluent: a review. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:275. [PMID: 38363444 DOI: 10.1007/s10661-024-12399-3] [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: 10/27/2023] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
The economic development of a country directly depends upon industries. But this economic development should not be at the cost of our natural environment. A substantial amount of water is spent during paper production, creating water scarcity and generating wastewater. Therefore, the Pollution Control Board classifies this industry into red category. Water is used in different papermaking stages such as debarking, pulping or bleaching, washing, and finishing. The wastewater thus generated contains lignin and xenobiotic compounds such as resin acids, chlorinated lignin, phenols, furans, dioxins, chlorophenols, adsorbable organic halogens (AOX), extractable organic halogens (EOCs), polychlorinated biphenyls, plasticizers, and polychlorinated dibenzodioxins. Nowadays, several microorganisms are used in the detoxification of these hazardous effluents. Researchers have found that microbial degradation is the most promising treatment method to remove high biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater. Microorganisms also remove AOX toxicity, chlorinated compounds, suspended solids, color, lignin, derivatives, etc. from the pulp and paper mill effluents. But in the current scenario, mill effluents are known to deteriorate the environment and therefore it is highly desirable to deploy advanced technologies for effluent treatment. This review summarizes the eco-friendly advanced treatment technologies for effluents generated from pulp and paper mills.
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Affiliation(s)
- Guddu Kumar Gupta
- Enzyme and Fermentation Technology Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, 124001, Haryana, India
| | - Rajeev Kumar Kapoor
- Enzyme and Fermentation Technology Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, 124001, Haryana, India.
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Zhang X, Han X, Liu Y, Han R, Wang R, Qu L. Remediation of water tainted with noxious aspirin and fluoride ion using UiO-66-NH 2 loaded peanut shell. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:93877-93891. [PMID: 37525078 DOI: 10.1007/s11356-023-28906-x] [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: 04/23/2023] [Accepted: 07/17/2023] [Indexed: 08/02/2023]
Abstract
One green adsorbent, UiO-66-NH2 modified peanut shell (c-PS-MOF), was prepared in a green synthetic route for improving the capture level of aspirin (ASP) and fluoride ion (F-). The adsorption properties of c-PS-MOF were evaluated by batch experiments and its physicochemical properties were explored by various characterization methods. The results showed that c-PS-MOF exhibited a wide range of pH applications (ASP: 2-10; F-: 3-12) and high salt resistance in the capturing processes of ASP and F-. The unit adsorption capacity of c-PS-MOF was as high as 84.7 mg·g-1 for ASP as pH = 3 and 11.2 mg·g-1 for F- under pH = 6 at 303 K from Langmuir model, respectively. When the solid-liquid ratio was 2 g·L-1, the content of ASP (C0 = 100 mg·L-1) and F- (C0 = 20 mg·L-1) in solution can be reduced to 0.48 mg·L-1 and 1.05 mg·L-1 separately. The recycling of c-PS-MOF can be realized with 5 mmol·L-1 NaOH as eluent. Analysis of simulated water samples showed that c-PS-MOF could be used to remove ASP and F- from actual water. The c-PS-MOF is promising to bind ASP and F- from rivers, lakes, etc.
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Affiliation(s)
- Xiaoting Zhang
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China
| | - Xiaoyu Han
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China
| | - Yang Liu
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China
| | - Runping Han
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China.
| | - Rong Wang
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China
| | - Lingbo Qu
- College of Chemistry, Zhengzhou University, No 100 of Ke Xue Road, Zhengzhou, 450001, People's Republic of China
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Saira GC, Shanthakumar S. Zero waste discharge in tannery industries - An achievable reality? A recent review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 335:117508. [PMID: 36812686 DOI: 10.1016/j.jenvman.2023.117508] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/03/2023] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
In the recent times, more attention is on industrial waste management due to the unaffordable space for dump yards and landfills and the increased charges for waste dumping. Even though the vegan revolution and plant-based meat products are booming, the traditional slaughterhouses and the wastes produced by them continue to be a concern. Waste valorisation is an established procedure striving to create a closed chain process in industries where there is no refuse. Although a highly polluting industry, slaughterhouse industry wastes have been recycled to economically viable leather since ancient times. However, the tannery industry is causing pollution in par with or even more than the slaughterhouses. Effective management of the liquid and solid wastes from the tannery is of utmost concern because of its toxicity. The hazardous wastes generated enter the food chain, causing long term impacts in the ecosystem. Several leather waste transformation processes are widely used in the industries, and they are yielding good products of economic value. However careful exploration into the processes and products of waste valorisation are often ignored as long as the transformed waste product is of higher value than the waste. The most efficient and environmentally friendly waste management technique should convert the refuse into a value-added utilization without any toxic leftovers. Zero waste concept is an extension of the zero liquid discharge concept, where the solid waste is also treated and reused to such an extent that there is no residue to be sent to the landfill. This review initially presents the existing methods for the de-toxification of tannery wastes and examines the possibility of solid waste management within the tannery industry to attain zero waste discharge.
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Affiliation(s)
- G C Saira
- Department of Environmental and Water Resources Engineering, School of Civil Engineering, Vellore Institute of Technology (VIT), Vellore, 632014, India
| | - S Shanthakumar
- Centre for Clean Environment, Vellore Institute of Technology (VIT), Vellore, 632014, India.
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Camparotto NG, Paixão GR, Brião GDV, Oliveira RL, Prediger P, Vieira MGA. Comparative effect of mesoporous carbon doping on the adsorption of pharmaceutical drugs in water: Theoretical calculations and mechanism study. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 99:104105. [PMID: 36893890 DOI: 10.1016/j.etap.2023.104105] [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: 12/16/2022] [Revised: 02/10/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
In this study, mesoporous doped-carbons were synthesized from sucrose, a natural source, boric acid and cyanamide as precursors, generating B- or N-doped carbon. These materials were characterized by FTIR, XRD, TGA, Raman, SEM, TEM, BET, and XPS, confirming the preparation of a tridimensional doped porous structure. B-MPC and N-MPC showed a high surface specific area above 1000 m2/g. The effect of B and N doping on mesoporous carbon was evaluated on the adsorption of emerging pollutants from water. Diclofenac sodium and paracetamol were used in adsorption assays, reaching removal capacities of 78 and 101 mg.g-1, respectively. Kinetic and isothermal studies indicate the chemical nature of adsorption controlled by external and intraparticle diffusion and multilayer formation due to strong adsorbent/adsorbate interactions. DFT-based calculations and adsorption assays infer that the main attractive forces are hydrogen bonds and Lewis acid-base interactions.
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Affiliation(s)
| | - Gustavo Rocha Paixão
- School of Technology, University of Campinas, 13484-332 Limeira, São Paulo, Brazil
| | - Giani de Vargas Brião
- School of Chemical Engineering, University of Campinas, 13083-82 Campinas, São Paulo, Brazil
| | - Rafael L Oliveira
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, 50-422 Wroclaw, Poland
| | - Patrícia Prediger
- School of Technology, University of Campinas, 13484-332 Limeira, São Paulo, Brazil.
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Moreira WM, Viotti PV, de Moura AA, Gimenes ML, Vieira MGA. Synthesis of a biobased resin and its screening as an alternative adsorbent for organic and inorganic micropollutant removal. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:79935-79953. [PMID: 35091942 DOI: 10.1007/s11356-021-18250-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
The sol-gel route was used to synthesize a biophenolic resin from a blend of Kraft black liquor and condensed tannin. The biobased resin has an amorphous structure and diversified surface functional groups. The biomaterial thermal stability was improved by Kraft black liquor, which increased the fixed carbon yield by 19.78% in an oxidant medium and 9.07% in an inert medium. Moreover, the presence of fixed carbon and char is positively related to the material flame retardant property. Additionally, impedance measurements were used to understand the physical phenomena occurring at the polymeric matrix's interface and the material's final properties. The biobased resin characterization and the considerable increase in the presence of micropollutants in surface and water bodies suggest the new biomaterial application in the adsorption process. Thus, its adsorption capacity toward several organic and inorganic micropollutants and its effectiveness in complex water matrices were evaluated. Methylene blue was used as a model compound to assess the influence of the resin composition on the adsorption capacity, and the type H isotherm indicates the high affinity of the biobased resin toward the micropollutant. The adsorption occurs in multilayer by intermolecular interaction and electrostatic forces. The amount of Kraft black liquor favored the adsorption, and the adsorption capacity was greater than 1250 mg g-1. When inorganic compounds were evaluated, the carboxyl and phenol groups favor the biomaterial affinity toward metal ions. Cu2+ and Ni2+ were completely removed from the contaminated water, and the adsorption capacity of the other inorganic compounds was: Pb2+ (36.97 mg g-1), Al3+ (22.17 mg g-1), Ba2+ (12.76 mg g-1), Ag1+ (33.85 mg g-1), and Fe2+ (19.44 mg g-1). In contrast, the adsorption capacity of the organic micropollutants was: 2,4-D (3.09 mg g-1), diuron (5.89 mg g-1), atrazine (2.71 mg g-1), diclofenac (2.04 mg g-1), caffeine (5.79 mg g-1), acetaminophen (4.80 mg g-1), methylene Blue (106.66 mg g-1), and methyl orange (30.48 mg g-1). The results pointed that the adsorption efficiency of organic micropollutants increases with the distribution coefficient (logD), indicating the biobased resin affinity toward more lipophilic compounds and ionized species.
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Affiliation(s)
- Wardleison Martins Moreira
- School of Chemical Engineering, University of Campinas, Albert Einstein Avenue, Campinas, São Paulo, 50013083-852, Brazil.
- Department of Chemical Engineering, State University of Maringá, Avenida Colombo, Maringá, Paraná, 579087020-900, Brazil.
| | - Paula Valéria Viotti
- Department of Chemical Engineering, State University of Maringá, Avenida Colombo, Maringá, Paraná, 579087020-900, Brazil
| | - Alexandre Amado de Moura
- Department of Chemical Engineering, State University of Maringá, Avenida Colombo, Maringá, Paraná, 579087020-900, Brazil
| | - Marcelino Luiz Gimenes
- Department of Chemical Engineering, State University of Maringá, Avenida Colombo, Maringá, Paraná, 579087020-900, Brazil
| | - Melissa Gurgel Adeodato Vieira
- School of Chemical Engineering, University of Campinas, Albert Einstein Avenue, Campinas, São Paulo, 50013083-852, Brazil
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Malesic-Eleftheriadou N, Liakos EV, Evgenidou E, Kyzas GZ, Bikiaris DN, Lambropoulou DA. Low-cost agricultural wastes (orange peels) for the synthesis and characterization of activated carbon biosorbents in the removal of pharmaceuticals in multi-component mixtures from aqueous matrices. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Țurcanu AA, Matei E, Râpă M, Predescu AM, Berbecaru AC, Coman G, Predescu C. Walnut Shell Biowaste Valorization via HTC Process for the Removal of Some Emerging Pharmaceutical Pollutants from Aqueous Solutions. Int J Mol Sci 2022; 23:ijms231911095. [PMID: 36232389 PMCID: PMC9570237 DOI: 10.3390/ijms231911095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
This research emphasizes the performance of some eco-friendly carbon materials as hydrochars (HC) obtained by the hydrothermal carbonization (HTC) process applied to walnut shell (WS) biowaste. These materials display promising properties that can be used for environmental applications such as emerging pharmaceutical pollutant retention from water sources. Thus, three hydrochars coded HCWS1, HCWS2, and HCWS3 were obtained using a dynamic autoclave in specific conditions—temperature of 220 °C, autogenous pressure, 1:10 biomass–water weight ratio—and for three different reaction times, 1 h, 6 h, and 12 h. The HCWSs were characterized by means of ATR-FTIR and SEM-EDS analyses and tested as possible adsorbents to assess the removal efficiencies of some emerging pharmaceutical pollutants (paracetamol and methylene blue) by UV–VIS spectrophotometry. Kinetic and adsorption studies were carried out. The best results were obtained for the HCWS3 hydrochar. Further perspectives include an activation step of the hydrochars and their testing on other emerging pharmaceutical pollutants.
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Sanz-Santos E, Álvarez-Torrellas S, Larriba M, Calleja-Cascajero D, García J. Enhanced removal of neonicotinoid pesticides present in the Decision 2018/840/EU by new sewage sludge-based carbon materials. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 313:115020. [PMID: 35398643 DOI: 10.1016/j.jenvman.2022.115020] [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: 10/21/2021] [Revised: 03/03/2022] [Accepted: 04/03/2022] [Indexed: 06/14/2023]
Abstract
Due to the increasingly strict legislation about the disposal of sewage sludge, it is necessary to find sustainable solutions to manage this waste at low-cost conditions. In addition, priority contaminants are now attracting much attention since they are usually detected in WWTP effluents. In this work, five sludge have been used as precursors for the synthesis of activated carbons subsequently tested in the removal by adsorption of three neonicotinoid pesticides listed in the EU Watch List: acetamiprid (ACT), thiamethoxam (THM), and imidacloprid (IMD). Generally, the activated carbons were prepared by chemical activation using ZnCl2 as an activating agent and then the resulting materials were pyrolyzed at 800 °C for 2 h. The synthesized activated carbons showed different textural properties; thus, the best adsorption results were found for AC-Industrial activated carbon, obtained from an industrial origin sewage sludge, with high equilibrium adsorption capacities (qe = 104.2, 137.0, and 119.9 mg g-1), for ACT, THM, and IMD, respectively. Furthermore, it was elucidated that the use of CO2 in the synthesis generated an opening, followed by widening, of the narrowest microporosity, increasing the specific surface area of the carbon materials. The kinetic and isotherm adsorption experimental data were obtained for each of the pesticide-activated carbon systems; thus, the kinetic curves were well-fitted to the pseudo-second-order kinetic model, as well as, Freundlich and Guggenheim-Anderson-de Boer (GAB) empirical models were used for the fitting of the equilibrium adsorption isotherms, finding that GAB model best fitted the experimental data. Additionally, the regeneration of the activated carbons using methanol as a regenerating agent and the single and simultaneous adsorption of a hospital wastewater effluent, fortified with the three studied pesticides have been explored.
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Affiliation(s)
- Eva Sanz-Santos
- Catalysis and Separation Processes Group, Chemical Engineering and Materials Department, Faculty of Chemistry, Complutense University, Avda. Complutense S/n, 28040, Madrid, Spain
| | - Silvia Álvarez-Torrellas
- Catalysis and Separation Processes Group, Chemical Engineering and Materials Department, Faculty of Chemistry, Complutense University, Avda. Complutense S/n, 28040, Madrid, Spain.
| | - Marcos Larriba
- Catalysis and Separation Processes Group, Chemical Engineering and Materials Department, Faculty of Chemistry, Complutense University, Avda. Complutense S/n, 28040, Madrid, Spain
| | - David Calleja-Cascajero
- Catalysis and Separation Processes Group, Chemical Engineering and Materials Department, Faculty of Chemistry, Complutense University, Avda. Complutense S/n, 28040, Madrid, Spain
| | - Juan García
- Catalysis and Separation Processes Group, Chemical Engineering and Materials Department, Faculty of Chemistry, Complutense University, Avda. Complutense S/n, 28040, Madrid, Spain
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Bernal V, Giraldo L, Moreno-Piraján JC. Understanding the solid-liquid equilibria between paracetamol and activated carbon: Thermodynamic approach of the interactions adsorbent-adsorbate using equilibrium, kinetic and calorimetry data. JOURNAL OF HAZARDOUS MATERIALS 2021; 419:126432. [PMID: 34174624 DOI: 10.1016/j.jhazmat.2021.126432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/01/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
In this work, we presented the paracetamol-activated carbon interactions and their effect on the adsorption capacity. We evaluated kinetic, equilibrium, and calorimetric data using different solvents (water, HCl 0.1 M, and NaCl 0.1 M) to evaluate the changes in the adsorbent-adsorbate interaction. In addition, the commercial activated carbon (AC) was modified through thermal (ACTT) and chemical (ACNA) methods to change the physicochemical properties of the adsorbents. The relative kinetic constants decrease with the content of basic groups on the activated carbon, indicating a lower influence of diffusion on the adsorption rate when the chemical interactions increase (0.1 ACNA >0.09 AC >0.03 ACTT mmol g-1). The adsorption capacity for AC at acidic pH increases slightly compared to tests carried out in the water. Under this condition, the adsorbed amount of paracetamol was 1.31 mmol g-1. However, the maximum adsorption capacity was achieved on ACTT using water as solvent (1.57 mmol g-1). The paracetamol adsorbed decreases in NaCl (osmotic, ionic strength) on all activated carbons by around 20%. The interaction enthalpy of the paracetamol-activated carbon interaction presents values between - 18.0 and 2.3 J per molecule adsorbed. The Gibbs energy released during the adsorption process is between - 33.1 and - 29.8 kJ mol-1.
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Affiliation(s)
- Valentina Bernal
- Departamento de Química, Universidad de los Andes, Cra. 1a No. 18A, 10, Bogotá, D. C., Colombia.
| | - Liliana Giraldo
- Departamento de Química, Universidad Nacional de Colombia, Cra 30 No. 45-03, Bogotá, D. C., Colombia.
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Application of Sludge-Based Activated Carbons for the Effective Adsorption of Neonicotinoid Pesticides. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11073087] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The amount of sludge produced in wastewater treatment plants (WWTPs) has increased over the years, and the methods used to reduce this waste, such as incineration, agricultural use, or disposal in landfills, cause problems of secondary pollution. For this reason, it is necessary to find sustainable and low-cost solutions to manage this waste. Additionally, emerging and priority pollutants are attracting attention from the scientific community as they can generate health problems due to inadequate removal in conventional WWTPs. In this work, a pharmaceutical industry sludge was used as a precursor in the synthesis of four activated carbons (ACs) using different activating agents (ZnCl2, FeCl3∙6H2O, Fe(NO3)3∙9H2O, and Fe(SO4)3∙H2O), to be used for the removal by adsorption of three neonicotinoid pesticides included in latest EU Watch List (Decision 2018/840): acetamiprid (ACT), thiamethoxam (THM), and imidacloprid (IMD). The prepared ACs showed micro–mesoporous properties, obtaining relatively slow adsorption kinetics to reach equilibrium, but despite this, high values of adsorption capacity (qe) were obtained. For example, for AC-ZnCl2 (SBET = 558 m2/g), high adsorption capacities of qe = 128.9, 126.8, and 166.1 mg/g for ACT, THM, and IMD, respectively, were found. In most cases, the adsorption isotherms showed a multilayer profile, indicating an important contribution of the mesoporosity of the activated carbons in the adsorption process.
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