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Li B, Tang M, Wang P, Liu S, Yao M, Dong J. A new method of alkalinity remediation for Cd-contaminated groundwater by PAAS-modified MgCO 3/Mg(OH) 2 colloid. Chemosphere 2024; 359:142200. [PMID: 38697565 DOI: 10.1016/j.chemosphere.2024.142200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/24/2024] [Accepted: 04/28/2024] [Indexed: 05/05/2024]
Abstract
Mg(OH)2 dissolves slowly and can provide a long-term source of alkalinity, thus a promising alternative reagent for the in situ remediation of heavy metal polluted groundwater. Unfortunately, it exhibits a relatively poor stabilization effect on heavy metal Cd due to the higher solubility of the resulting stabilized product, Cd(OH)2. To overcome this limitation, we investigated the use of MgCO3/Mg(OH)2 colloid modified by sodium polyacrylate (PAAS) to remove Cd from groundwater. Through ultrasonic dispersion, the molecular chains of PAAS are broken, causing a transformation from flocculation to surface modification, resulting in the production of a stable colloid. The colloidal particles of MgCO3/Mg(OH)2 have a smaller size and a negatively charged surface, which significantly enhances their migration ability in aquifers. The combination of MgCO3 and Mg(OH)2 provides a complementary effect, where MgCO3 effectively precipitates Cd in the aquifer while Mg(OH)2 maintains the required pH level for stabilization. The optimal compounding ratio of MgCO3 to Mg(OH)2 for achieving the best stabilization effect on Cd is found to be 1:1. Column experiments demonstrate that the injection of MgCO3/Mg(OH)2 colloid substantially enhances Cd stability, reducing the exchangeable fraction of Cd in aquifer media from 88.61% to a range of 22.50-34.38%. Based on these results, the MgCO3/Mg(OH)2 colloid shows great potential as a reactive medium for remediating Cd-contaminated groundwater.
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Affiliation(s)
- Bowen Li
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), 1#, Dongsanlu, Erxianqiao, Chengdu 610059. China.
| | - Meiling Tang
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), 1#, Dongsanlu, Erxianqiao, Chengdu 610059. China
| | - Peng Wang
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), 1#, Dongsanlu, Erxianqiao, Chengdu 610059. China
| | - Shibin Liu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), 1#, Dongsanlu, Erxianqiao, Chengdu 610059. China
| | - Meng Yao
- School of Environmental Science and Engineering, Changzhou University, Changzhou, 213164, China
| | - Jun Dong
- Key Lab of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun 130026, China
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Fang T, Wang T, Zhao M, Bai L, Deng Y, Ruan W. Food waste digestate composting enhancement by sodium polyacrylate addition: Effects on nitrogen transformation processes and bacterial community dynamics. J Environ Manage 2023; 325:116531. [PMID: 36308788 DOI: 10.1016/j.jenvman.2022.116531] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/03/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
The influences of sodium polyacrylate (PAAS) at the ratios of 0% (CK), 0.5% (F1), 1.0% (F2), 1.5% (F3), 2.0% (F4) and 2.5% (F5) on nitrogen transformation and bacterial community composition were investigated in the composting of food waste digestate (FWD) and corn straw (CS). PAAS addition increased the thermophilic temperature but had no significant effect on pH values. PAAS exerted significantly effects on the concentration of total nitrogen (TN), ammonia nitrogen (NH4+-N), nitrite-nitrogen (NO2--N) and nitrate-nitrogen (NO3--N). The compost product in 1.0% PAAS treatment was more active in absorbing nutrients. Firmicutes (9.40-83.54%), Actinobacteriota (9.98-51.50%), Proteobacteria (0.20-27.87%) and Bacteroidota (0.11-34.69%) were the dominant phyla in FWD composting. Moreover, relative to CK, PAAS promoted the propagation of dominant bacterial phyla Firmicutes with increment of 30.05-102.06% in the thermophilic phase. Kroppenstedtia, Thermobifida and Saccharomonospora were observed to be dominant at the maturing phase and correlated with NH4+-N, NO2--N, TN and NO3--N. Therefore, they might be regarded as probable biomarkers symbolic for the maturing phase during FWD composting. The compost product had the highest maturity degree in 1.0% PAAS treatment. These results indicated that PAAS addition improved the maturity and nutrient contents of the compost product as well as altered compost bacterial community dynamics.
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Affiliation(s)
- Tigao Fang
- School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Jiangnan University, Wuxi, 214122, China
| | - Tao Wang
- School of Environment Engineering, Wuxi University, Wuxi, 214105, China
| | - Mingxing Zhao
- School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Jiangnan University, Wuxi, 214122, China.
| | - Ling Bai
- Sichuan University of Science & Engineering, Zigong, Sichuan, 643000, China
| | - Yun Deng
- School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Jiangnan University, Wuxi, 214122, China
| | - Wenquan Ruan
- School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology & Material, Suzhou, 215009, China.
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Li SS, Song YL, Yang HR, An QD, Xiao ZY, Zhai SR. Modifying alginate beads using polycarboxyl component for enhanced metal ions removal. Int J Biol Macromol 2020; 158:493-501. [PMID: 32389652 DOI: 10.1016/j.ijbiomac.2020.05.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/20/2020] [Accepted: 05/05/2020] [Indexed: 12/18/2022]
Abstract
Designing desirable adsorbent for highly efficient removal of heavy metal ions is of practical significance, given the cost-effectiveness, environmental benign, natural abundance and easy-handling collection features. Herein, a bead-like adsorbent with high adsorption capacity was prepared by modifying alginate beads using polyacrylate with high density of carboxyl groups. The developed alginate/polyacrylate beads were collaboratively characterized by FT-IR, TGA, SEM, XPS, etc., and various adsorption conditions were tested including the pH of the solution, contact time and the initial concentration. The experimental data were fitted well by the Freundlich isotherm model, and the maximum adsorption capacity was obtained from the Langmuir model was 611.0 mg/g, and adsorption process followed the Pseudo-second-order kinetic model. The adsorption mechanisms conformed to multi-layer adsorption, and mainly dominated by chemical interactions. The bead-like adsorbent exhibited excellent reusability after eight sequential cycles and displayed higher adsorption capacity towards lead ions. This type of adsorbent might possess promising role in treating heavy metals from water by virtue of degradable, cost-effective component and high adsorption efficiency.
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Affiliation(s)
- Shan-Shan Li
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Yi-Li Song
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Hua-Rong Yang
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Qing-Da An
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
| | - Zuo-Yi Xiao
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Shang-Ru Zhai
- Faculty of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
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Balasubramanian V, Velappan B, Vijayan SK, Jabamani H, Nagarajan V, Victor JS, Ranganath SP, Badiger MV, Chinnaraj VK, Chellappa M. Studies on the use of sodium polyacrylate (SPA) for low-salt animal skin preservation. Environ Sci Pollut Res Int 2019; 26:27100-27111. [PMID: 31317432 DOI: 10.1007/s11356-019-05871-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/28/2019] [Indexed: 06/10/2023]
Abstract
Salt-based preservation is practiced for decades in the leather industry because of its versatility, cost-effectiveness, and availability. The salt removed from the soaking process causes significant pollution including organic and elevated total dissolved solids (TDS). Hence, a low-salt skin preservation method using commercial sodium polyacrylate with a reduced quantity of sodium chloride aiming to retain leather properties and pollution reduction was the principal focus of the study. Commercial sodium polyacrylate initially characterized for water absorption capacity along with structural and functional properties is confirmed by NMR and IR spectroscopic techniques. In preliminary experiments, the process parameters attained optimized conditions of sodium polyacrylate (SPA) quantity (5%), a minimal amount of salt (15%), and contact time (4 h) required for skin preservation. Besides, reusability studies after SPA recovery (95%) were applied to skins with an optimized quantity of SPA and salt subsequently stored for 15 days along with control (40% salt). The results revealed that SPA with low salt aided an adequate curing efficiency with a substantial reduction (> 65%) of TDS and comparable physical and organoleptic properties on par with the conventional method. Overall, SPA supported low-salt skin preservation reduces pollutant load (TDS) caused due to using of 40% sodium chloride in the conventional curing process.
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Affiliation(s)
| | - Brindha Velappan
- Chemical Engineering Department, CSIR-Central Leather Research Institute, Adyar, Chennai, Tamil Nadu, 600020, India
| | - Sandhya Kurvilla Vijayan
- Chemical Engineering Department, CSIR-Central Leather Research Institute, Adyar, Chennai, Tamil Nadu, 600020, India
| | - Hepzibah Jabamani
- Chemical Engineering Department, CSIR-Central Leather Research Institute, Adyar, Chennai, Tamil Nadu, 600020, India
| | - Vedaraman Nagarajan
- Chemical Engineering Department, CSIR-Central Leather Research Institute, Adyar, Chennai, Tamil Nadu, 600020, India.
| | - John Sundar Victor
- Leather Processing Division, CSIR-Central Leather Research Institute, Adyar, Chennai, 600020, India
| | - Suresha P Ranganath
- Polymer Science and Engineering Division, CSIR-National Chemical Laboratory, Pune, 411008, India
| | - Manohar V Badiger
- Polymer Science and Engineering Division, CSIR-National Chemical Laboratory, Pune, 411008, India
| | | | - Muralidharan Chellappa
- Leather Processing Division, CSIR-Central Leather Research Institute, Adyar, Chennai, 600020, India
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Maruthupandy M, Seo J. Allyl isothiocyanate encapsulated halloysite covered with polyacrylate as a potential antibacterial agent against food spoilage bacteria. Mater Sci Eng C Mater Biol Appl 2019; 105:110016. [PMID: 31546351 DOI: 10.1016/j.msec.2019.110016] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 03/20/2019] [Accepted: 07/25/2019] [Indexed: 01/23/2023]
Abstract
Allyl isothiocyanate (AITC) is a highly volatile organic compound that is a potential antibacterial agent against food spoilage bacteria. Naturally formed halloysite nanotubes (HNTs) have a length of 1 μm and diameter ranging from 10 to 50 nm. The biocompatibility of HNT allows safe release of drugs to bacterial cells at a relatively low concentration compared to other systems. We encapsulated AITC inside HNTs that were then coated with sodium polyacrylate (PA). The HNT-AITC-PA nanocomposites (NCs) were characterized by Fourier-transform infrared spectroscopy, thermal gravimetric, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy analyses. In vitro antibacterial activity was evaluated against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria capable of food spoilage. HNT-AITC-PA NCs effectively inhibited the growth of both bacteria. The activity was pronounced against E. coli at 100 μg/mL, with concentrations of 25 μg/mL and 200 μg/mL reducing the viable cell population by 41% and 96%, respectively. Thus, HNT-AITC-PA NCs are a novel and promising material against food spoilage bacteria for use in active antibacterial food packaging.
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Affiliation(s)
- Muthuchamy Maruthupandy
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea
| | - Jongchul Seo
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea.
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Wickstone L, Shayah A, Agada F. Risk of asphyxiation from Vernagel ingestion. Ann R Coll Surg Engl 2018; 100:e176-e177. [PMID: 29909673 DOI: 10.1308/rcsann.2018.0104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vernagel (sodium polyacrylate) is a powder commonly used in hospitals worldwide for the management and disposal of body fluids. It reacts with fluids to form a semisolid gel. Its main use is to reduce spillages. If ingested, this substance presents significant risk of asphyxiation. There have been 15 reported cases of Vernagel ingestion in 6 years and 1 death from asphyxiation. We present the case of an elderly patient who was admitted following a fall. He accidentally ingested a sachet of Vernagel during the early hours of the morning. An urgent rigid panendoscopy was performed and the material was evacuated using suction aspiration. Patients should be supervised when using Vernagel on the ward, to avoid ingestion. Ear, nose and throat doctors should be aware of Vernagel and its properties. Owing to the risk of airway obstruction, excellent coordination between the anaesthetist and surgeon is crucial, and prompt management is required.
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Affiliation(s)
- L Wickstone
- York Teaching Hospital NHS Foundation Trust , UK
| | - A Shayah
- York Teaching Hospital NHS Foundation Trust , UK
| | - F Agada
- York Teaching Hospital NHS Foundation Trust , UK
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