Chromium removal from ion-exchange (IX) brines presents a serious challenge to the water industry. Although chromium removal with calcium polysulfide (CaS(5)) from drinking waters has been investigated somewhat, its removal from ion-exchange brines has not been evaluated to date. In this study, a Central Composite Design as well as experimental coagulation tests were performed to investigate the influence of pH, CaS(5)/Cr(VI) molar ratio, alkalinity, and ionic strength in the removal of chromium from IX brines. The optimal pH range for the process was found to be pH 8-10.3 and brine alkalinity did not affect coagulation. The efficiency of chromium removal improved only slightly when the ionic strength increased from 0.1 M to 1.5 M; no significant difference was observed for an ionic strength change from 1.5 to 2.1 M. For chromium (VI) concentrations typically found in ion-exchange brines, a CaS(5)/Cr(VI) molar ratio varying from 0.6 to 1.4 was needed to obtain a final chromium concentration <5 mg/L. Maximum efficiency for total chromium removal was obtained when oxidation reduction potentials were between -0.1 and 0 (V). Solids concentrations (0.2-1.5 g/L) were found to increase proportionally with CaS(5) dosage. The results of this research are directly applicable to the treatment of residual waste brines containing chromium.
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http://dx.doi.org/10.1016/j.watres.2011.03.006 | DOI Listing |
Water Sci Technol
January 2025
School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China E-mail:
Ultrafiltration membranes are widely used in the treatment of surface water. However, membrane fouling is a core issue that needs to be addressed in its application. Magnetotactic bacteria (MTB) show early film-forming and magnetotactic behaviour in the presence of external magnetic fields.
View Article and Find Full Text PDFJ Bone Joint Surg Am
January 2025
Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, NY.
Background: Antiseptic solutions are commonly utilized during total joint arthroplasty (TJA) to prevent and treat periprosthetic joint infection (PJI). The purpose of this study was to investigate which antiseptic solution is most effective against methicillin-sensitive Staphylococcus aureus (MSSA) and Escherichia coli biofilms established in vitro on orthopaedic surfaces commonly utilized in total knee arthroplasty: cobalt-chromium (CC), oxidized zirconium (OxZr), and polymethylmethacrylate (PMMA).
Methods: MSSA and E.
Inorg Chem
January 2025
School of Life and Environmental Sciences, Shaoxing University, Huancheng West Road 508, Shaoxing 312000, P.R. China.
In this work, bimetallic organic frameworks NH-MOFs(Fe, Ti) with different Fe/Ti molar ratios were prepared by a hydrothermal method for the synchronous redox transformation of Cr(VI) and As(III). These results showed that NH-MIL-125(Ti) was less effective in the photocatalytic removal of Cr(VI), whereas NH-MIL-88B(Fe) was less effective in the photocatalytic oxidative removal of As(III). Due to the introduction of Fe, the photocatalytic reduction removal of Cr(VI) (23.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Sichuan Academy of Forestry, Chengdu, Sichuan 610081, China; Ecological Restoration and Conservation on Forest and Wetland Key Laboratory of Sichuan Province, Chengdu, Sichuan 610081, China. Electronic address:
Lignocellulosic waste is a prevalent byproduct of agricultural and forestry activities which is an excellent feedstock for the preparation of biochar. This research area is of interest to the scientific community due to its potential in environmental remediation. In this regard, this review examines the latest advancements in transforming lignocellulosic waste into biochar and explores recent innovations in enhancing its functionality for chromium ion removal.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Environmental Science and Engineering, Hainan University, Haikou 570228, China; Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environmental Science and Engineering, Hainan University, Haikou 570228, China. Electronic address:
Microbe-Assisted Phytoremediation (MAP) is an eco-friendly method for remediating soil contaminated with heavy metals such as cadmium (Cd) and chromium (Cr). This study demonstrates the potential of a king grass-Serratia marcescens strain S27 (KS) co-symbiotic system to enhance heavy metal remediation. The KS symbiosis increased the biomass of king grass by 48 % and enhanced the accumulation of Cd and Cr in the whole plant by 2.
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