Article
Biochemistry & Molecular Biology
Anca Andreea Turcanu, Ecaterina Matei, Maria Rapa, Andra Mihaela Predescu, Andrei-Constantin Berbecaru, George Coman, Cristian Predescu
Summary: This research focuses on exploring the performance of eco-friendly carbon materials, specifically in the hydrothermal carbonization process using walnut shell biowaste. The study reveals that these materials possess promising properties for the removal of pharmaceutical pollutants from water sources. Among the hydrochars tested, HCWS3 demonstrates the highest adsorption efficiency. Future perspectives include the activation of hydrochars and testing them on other emerging pharmaceutical pollutants.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Environmental Sciences
Evans Dovi, Aaron Albert Aryee, Jianjun Li, Zhaohui Li, Lingbo Qu, Runping Han
Summary: The presence of emerging pollutants like PO43- and NO3- in water bodies has raised global concerns about their impact on water bodies and human health. ACWNS, a novel adsorbent, was found to effectively remove phosphate and nitrate, showing exothermic and spontaneous adsorption. The adsorption mechanism is attributed to electrostatic interactions and hydrogen bonding, with ACWNS demonstrating a higher attraction towards the ions.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Agricultural Engineering
Kangqiang Li, Qi Jiang, Guo Chen, Lei Gao, Jinhui Peng, Quan Chen, Sivasankar Koppala, Mamdouh Omran, Jin Chen
Summary: The study shows that combining biomass pyrolysis with microwave heating technologies is an efficient way to reduce low-grade pyrolusite. The optimal reduction parameters include a reduction temperature of 650 degrees C, a holding time of 30 min, a M-bio/M-ore ratio of 1.8:10, and a microwave power of 1200 W.
BIORESOURCE TECHNOLOGY
(2021)
Article
Green & Sustainable Science & Technology
Vijayan Ramya, Devaraj Murugan, Chokkalingam Lajapathirai, Sivarajan Meenatchisundaram, Sivasamy Arumugam
Summary: Superparamagnetic nanoparticles/sludge biomass derived activated carbon composite was prepared and used for the removal of Cr (VI) from aqueous solution. The composite adsorbent had a large specific surface area and saturation magnetization, and showed high adsorption capacity for Cr (VI). The prepared composite adsorbent exhibited good stability and recyclability.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Agricultural Engineering
Qiyu Shi, Wangbo Wang, Hongmin Zhang, Huiling Bai, Kaiqiang Liu, Jianfeng Zhang, Zhihua Li, Weihuang Zhu
Summary: In this study, a high-performance porous adsorbent was prepared from biochar derived from walnut shells and effectively removed tetracycline (TC). The adsorbent exhibited a significantly increased specific surface area (SSA) and a maximum adsorption capacity for TC. It demonstrated high stability and reusability for TC adsorption under different conditions. The proposed adsorption mechanism involved pore filling, hydrogen bonding, p-p stacking, and electrostatic interaction. These findings have important implications for the development of biochar-based adsorbents for pollutant removal.
BIORESOURCE TECHNOLOGY
(2023)
Article
Environmental Sciences
Xinru Yang, Xueming Qin, Jiayin Xie, Xiaoyu Li, Huichao Xu, Yongsheng Zhao
Summary: Molasses have a significant effect on the bioremediation of Cr(VI) contaminated groundwater, stimulating its reduction and reducing toxicity on bacteria. Molasses has a higher removal efficiency compared to glucose or emulsified vegetable oil, with a higher remediation concentration and faster removal rate.
Article
Engineering, Environmental
Evans Dovi, Aaron Albert Aryee, Alexander Nti Kani, Farid Mzee Mpatani, Jianjun Li, Lingbo Qu, Runping Han
Summary: This research investigated the feasibility of using walnut shells functionalized with amino groups to remove hexavalent chromium ions from water. The study found that the functionalized walnut shell material had a high adsorption capacity for hexavalent chromium and could be used for efficient adsorption and regeneration. The results indicate that amino-functionalized walnut shells show potential for the removal of hexavalent chromium ions from wastewater.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Agricultural Engineering
Wenguang Wei, Nan Shang, Xun Zhang, Wen Liu, Tong Zhang, Min Wu
Summary: This study successfully prepared a chestnut thorns shell (CTS) sorbent with high adsorption performance using an ultrasound-assisted binary solvent system and low temperature ice crystal fixation. Further investigations revealed that the adsorption mechanism of CTS on MB involves electrostatic attraction, hydrogen bonding, ion-dipole interaction and pi-pi interaction.
BIORESOURCE TECHNOLOGY
(2022)
Article
Green & Sustainable Science & Technology
Sandra Pioquinto Garcia, Luis Angel Garza Rodriguez, Diana Bustos Martinez, Felipe de Jesus Cerino Cordova, Eduardo Soto Regalado, Sylvain Giraudet, Nancy Elizabeth Davila Guzman
Summary: The study investigates the potential use of raw and expanded perlite as low-cost adsorbents for biogas purification, finding that expanded perlite has moderate adsorption capacity and follows Linear-Driving Force model in adsorption kinetics.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Environmental Sciences
Asha Singh, Dinesh Arora, Renu Bala, Anil Khokhar, Sunil Kumar
Summary: In this study, nanoparticles prepared from aquatic plants Salvinia molesta and Typha latifolia were loaded onto powdered form to create nanocomposite adsorbents for wastewater treatment. The adsorption capacity, optimal working conditions, and mechanisms of the novel adsorbents were evaluated.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Engineering, Environmental
R. Sangeetha Piriya, Rajamani M. Jayabalakrishnan, M. Maheswari, Kovilpillai Boomiraj, Sadish Oumabady
Summary: This study focused on the activation of coconut-based agricultural wastes as an alternative adsorbent for removing pollutants from industrial effluents. The activated carbon exhibited a high specific surface area and stability, showing significant dye adsorption for malachite green removal. The experimental data fit the Freundlich isotherm model well, indicating the potential of the carbon material as an alternative energy source.
WATER SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Environmental
Tianyuan Gu, Wenjing Niu, Yongming Wu, Lili Huo, Zulfiqar Ahmad, Mi Deng, Hua Zhong
Summary: Molasses has potential for both chemical reduction and bioreduction of Cr(VI) in groundwater. Low concentration of molasses can significantly enhance bioreduction of Cr(VI) and outperforms sucrose. Bacillus sp., isolated from the site soils, can reduce Cr(VI) using molasses as the sole carbon source.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Environmental Sciences
Hao-Tian Mao, Lun-Xing Chen, Meng-Ying Zhang, Qiu-Yun Shi, Hong Xu, Da-Yan Zhang, Zhong-Wei Zhang, Ming Yuan, Shu Yuan, Huai -Yu Zhang, Yan-Qiu Su, Yang -Er Chen
Summary: In this study, R. sphaeroides SC01 and melatonin were employed to remove hexavalent chromium from wastewater. The results showed that exogenous melatonin could alleviate oxidative damage, enhance the absorption capacity of cell membranes, and improve the reduction efficiency of hexavalent chromium. Melatonin application led to significant upregulation of ascorbic acid, glutathione, and cysteine, and promoted the bioprecipitation of CrPO4·6H2O. These findings highlight the important role of melatonin in the reduction and uptake of hexavalent chromium, making it a promising strategy for the remediation of contaminated wastewater by photosynthetic bacteria.
ENVIRONMENTAL POLLUTION
(2023)
Article
Multidisciplinary Sciences
Rajni Garg, Rishav Garg, Mika Sillanpaa, Mohammad Amir Alimuddin, Mohammad Amir Khan, Nabisab Mujawar Mubarak, Yie Hua Tan
Summary: This study demonstrates the use of waste walnut shells as a biosorbent for removing Cr(VI) from water. The shells were chemically modified to enhance their adsorption properties. The adsorption of Cr(VI) followed the Langmuir model, and the maximum adsorption capacity was achieved for the chemically modified shells. Treatment with sodium hydroxide and citric acid further improved the adsorption efficiency. The adsorption process was found to be endothermic and spontaneous, following pseudo-second-order kinetics.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Multidisciplinary
Feng Gao, Lei Zhang, Libin Yang, Xuefei Zhou, Yalei Zhang
Summary: Three types of graphene oxides (GOs) were prepared and used for the removal of Cr(VI). The adsorption performance of GOs was affected by initial concentration, pH, adsorbent dosage, contact time, and temperature. The adsorption mechanisms involved redox reaction, electrostatic attraction, pore filling, ion exchange, and complexation. The adsorption processes were mainly monolayer chemisorption and equilibrium could be reached in 30 min. The saturation adsorption capacities of GO-M1, GO-M2, and GO-M3 for Cr(VI) were estimated to be 3.5412 mg.g(-1), 2.3631 mg.g(-1), and 7.0358 mg.g(-1), respectively. The adsorption processes of Cr(VI) by GOs were endothermic, entropy-driven, and thermodynamically spontaneous and feasible. These findings provide important insights into the mechanism and application of Cr(VI) removal by GOs.
Article
Multidisciplinary Sciences
Huichen Yang, Rui Hu, Hans Ruppert, Chicgoua Noubactep
Summary: Iron corrosion in Fe-0-based permeable reactive barriers can lead to significant porosity loss and system failure. A mathematical model was presented in this study to describe the porosity change and the impact of in-situ generated FeCPs. The model results suggest that previous models have underestimated the effects of FeCPs on porosity loss in PRBs.
SCIENTIFIC REPORTS
(2021)
Article
Environmental Sciences
Zuleikha Pembe-Ali, Tulinave Burton Mwamila, Mesia Lufingo, Willis Gwenzi, Janeth Marwa, Mwemezi J. Rwiza, Innocent Lugodisha, Qinwen Qi, Chicgoua Noubactep
Summary: The escalating salinity levels on small islands due to uncontrolled groundwater extraction can be addressed by the innovative Kilimanjaro Concept (KC) based on rainwater harvesting (RWH), which can remediate seawater intrusion while enabling a universal safe drinking water supply. The concept involves systematic harvesting and storage of rainwater, as well as affordable water treatment technologies. Further research should focus on pilot testing the concept on Unguja Island and other island nations.
Article
Green & Sustainable Science & Technology
Zhe Huang, Esther Laurentine Nya, Mohammad Azizur Rahman, Tulinave Burton Mwamila, Viet Cao, Willis Gwenzi, Chicgoua Noubactep
Summary: Rainwater harvesting is seen as a cost-effective alternative water resource for potable and non-potable uses, with benefits including reducing flood risks, recharging groundwater, and saving conventional water sources. It should be at the heart of global water management as it can be easily implemented even in low-resource situations.
Article
Green & Sustainable Science & Technology
Zhe Huang, Esther Laurentine Nya, Viet Cao, Willis Gwenzi, Mohammad Azizur Rahman, Chicgoua Noubactep
Summary: This article discusses the affordability of decentralized solutions for safe drinking water provision in low-income communities, highlighting the significant cost differences between technologies and the reliance on imported components in expensive technologies. In order to achieve the Sustainable Development Goal for safe drinking water, the promotion of DIY systems and further improvement of relevant technologies are essential.
Editorial Material
Engineering, Chemical
Chicgoua Noubactep
Summary: This special issue delves into the applicability, advantages, limitations, and methods of transforming existing water management systems with metallic iron as filter material, emphasizing the affordability and social acceptability of adsorptive filtration for decentralized safe drinking water provision. Through discussions on the efficiency on locally available materials and global applicability, the potential of water filtration for universal access to safe drinking water by 2030 is highlighted.
Review
Environmental Sciences
Viet Cao, Arnaud Igor Nde-Tchoupe, Rui Hu, Willis Gwenzi, Chicgoua Noubactep
Summary: The global effort to mitigate environmental pollution impact involves the use of metallic iron in various applications, but controversial discussions on contaminant removal mechanisms should consider the century-old theory of aqueous iron corrosion to enhance efficiency and sustainability of remediation systems.
Article
Environmental Sciences
Chicgoua Noubactep
Summary: This study highlights that iron (Fe(0)) is not an environmental reducing agent, and more science-based investigations are needed to optimize the operation of Fe(0) PRBs. Fe(0) PRBs should be regarded as particular cases of metal corrosion in porous media, with the key feature being that the extent of Fe0 corrosion temporally depends on the residual porosity.
Article
Environmental Sciences
Bernard Konadu-Amoah, Arnaud Igor Nde-Tchoupe, Rui Hu, Willis Gwenzi, Chicgoua Noubactep
Summary: The methylene blue method (MB method) is an innovative approach to characterize the reactivity of metallic iron (Fe-0) for aqueous contaminant removal. It is a semi-quantitative tool that considers the differential adsorptive affinity of methylene blue for sand and iron oxides. However, it only provides semi-quantitative information and further comprehensive investigations with microscopic and spectroscopic surface and solid-state analyses are needed to complement the results from the MB method.
Review
Environmental Sciences
Minhui Xiao, Rui Hu, Arnaud Igor Nde-Tchoupe, Willis Gwenzi, Chicgoua Noubactep
Summary: Scientific collaboration among research groups scattered across different locations on the topic of metallic iron (Fe-0) for water remediation has made significant progress in the past three decades. Recent analysis shows that the research community has divided itself into two schools of thought since about 2007, with limited progress in knowledge since then. One school believes that Fe-0 is a reducing agent for relevant contaminants, while the other argues that Fe-0 generates flocculants for contaminant scavenging and reducing species, but reductive transformation is not a relevant contaminant removal mechanism. The dominance of the first school in terms of supporters poses challenges in assessing the validity of both views. This could result in potential flaws in various derivations of the original Fe-0 remediation technology. Review articles are suggested for successful collaboration among researchers striving for the success of this promising yet unestablished technology.
Review
Environmental Sciences
Bernard Konadu-Amoah, Rui Hu, Arnaud Igor Nde-Tchoupe, Willis Gwenzi, Chicgoua Noubactep
Summary: The discharge of excessive phosphate from wastewater sources has become a major environmental threat. The use of metallic iron (Fe-0) for phosphate removal has received attention, as it generates positively charged iron corrosion products (FeCPs) with high affinity for anionic phosphate. This study critically reviews the utilization of Fe-0-based materials for aqueous phosphate removal and discusses the main removal mechanisms based on the chemistry of the Fe-0/H2O system.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Review
Environmental Sciences
Arnaud Igor Nde-Tchoupe, Bernard Konadu-Amoah, Nadege Gatcha-Bandjun, Rui Hu, Willis Gwenzi, Chicgoua Noubactep
Summary: This article critically evaluates the conventional Kanchan Arsenic Filter (KAF) and identifies the main reasons for its poor performance in removing arsenic. The study highlights the design limitations of the KAF and emphasizes the need to focus on the suitability of the technology rather than its sustainability. It suggests correcting the design mistakes and exploring alternative materials to improve the performance of the filter.
Review
Water Resources
Bernard Konadu-Amoah, Rui Hu, Viet Cao, Ran Tao, Huichen Yang, Arnaud Igor Nde-Tchoupe, Willis Gwenzi, Hans Ruppert, Chicgoua Noubactep
Summary: Metallic iron (Fe-0) has been widely used to remove toxics from water, but its role as an environmental reducing agent has been a subject of debate. This article challenges the prevailing view and aims to reconcile the efficient technology of Fe-0 remediation with its scientific roots, in order to design better remediation systems.
APPLIED WATER SCIENCE
(2022)
Article
Engineering, Civil
Huichen Yang, Quan Liu, Rui Hu, Thomas Ptak, Reza Taherdangkoo, Yuxi Liu, Chicgoua Noubactep
Summary: This paper presents a 3-D numerical model to assess the impact of porosity heterogeneity of a metallic iron based permeable reactive barrier (Fe0-PRB) on groundwater flow and long-term effectiveness. The study found that the porosity heterogeneity of the barrier medium is an important factor in estimating the long-term performance of a continuous-wall Fe0-PRB. Ignoring porosity heterogeneity leads to underestimation of flow and contaminant spread.
JOURNAL OF HYDROLOGY
(2022)
Article
Environmental Sciences
Viet Cao, Omari Bakari, Joseline Flore Kenmogne-Tchidjo, Nadege Gatcha-Bandjun, Arnaud Igor Nde-Tchoupe, Willis Gwenzi, Karoli N. Njau, Chicgoua Noubactep
Summary: Science denial refers to rejecting well-established views that are no longer questioned by scientists within a given community. This article retraces the path taken to question the reductive transformation concept and calls for alternative theories.
Article
Environmental Sciences
Xuesong Cui, Minhui Xiao, Ran Tao, Rui Hu, Hans Ruppert, Willis Gwenzi, Chicgoua Noubactep
Summary: The aim of this study was to develop a simple spectrophotometric method to characterize the intrinsic reactivity of granular metallic iron (gFe(0)). The AA method, based on the extent of iron dissolution in an ascorbic acid solution, was found to be more accurate and less expensive than the EDTA method. It should be routinely used to select and apply gFe(0) materials.
