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Ge R, E T, Cheng Y, Wang Y, Yu J, Li Y, Yang S. NaH 2PO 4 synergizes with organic matter to stabilize chromium in tannery sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119843. [PMID: 38128209 DOI: 10.1016/j.jenvman.2023.119843] [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: 09/26/2023] [Revised: 12/05/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023]
Abstract
Heavy metal stabilization is an effective method to treat chromium in tannery sludge. Here we show that mainly investigated NaH2PO4 (MSP) and organic matter (OM) to stabilize chromium in tannery sludge. The experimental investigation revealed that the addition of montmorillonite (MMT) and MSP samples showed a significant increase in the percentage of reducible and oxidizable Cr in the former compared to the samples with the addition of MMT. This is attributed to the formation of Cr-O bond, which allows the MSP to undergo an inner-sphere complexation reaction with the metal oxide of Cr via ligand exchange. Significantly, the MSP moiety adsorbs on the surface of OM through monodentate, which increases the adsorption sites of OM for Cr6+ and promotes the reduction of Cr6+ to Cr3+. Moreover, PO43- reacts with Cr3+ to produce CrPO4 precipitation, thus reducing the free Cr3+ content. Finally, DFT calculations confirmed that a ternary system is formed between PO43-, OM, and Cr, and the binding energy is negative, which indicated that PO43- could co-stabilize Cr with OM.
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Affiliation(s)
- Ruijie Ge
- Liaoning Key Laboratory for Chemical Clean Production, Liaoning Key Laboratory for Surface Functionalization of Titanium Dioxide Powder, Institute of Ocean Research, Institute Environmental Research, College of Chemistry and Material Engineering, Bohai University, Jinzhou, 121013, Liaoning, China
| | - Tao E
- Liaoning Key Laboratory for Chemical Clean Production, Liaoning Key Laboratory for Surface Functionalization of Titanium Dioxide Powder, Institute of Ocean Research, Institute Environmental Research, College of Chemistry and Material Engineering, Bohai University, Jinzhou, 121013, Liaoning, China
| | - Ying Cheng
- Liaoning Key Laboratory for Chemical Clean Production, Liaoning Key Laboratory for Surface Functionalization of Titanium Dioxide Powder, Institute of Ocean Research, Institute Environmental Research, College of Chemistry and Material Engineering, Bohai University, Jinzhou, 121013, Liaoning, China
| | - Yuanfei Wang
- Liaoning Huadian Environmental Testing Co., LTD, Jinzhou, 121013, Liaoning, China
| | - Jia Yu
- Environmental Protection Monitoring Station of Haining, Haining, 330481, Zhejiang, China
| | - Yun Li
- Chemistry & Chemical Engineering of College Yantai University, Yantai, 264005, Shandong, China.
| | - Shuyi Yang
- Liaoning Key Laboratory for Chemical Clean Production, Liaoning Key Laboratory for Surface Functionalization of Titanium Dioxide Powder, Institute of Ocean Research, Institute Environmental Research, College of Chemistry and Material Engineering, Bohai University, Jinzhou, 121013, Liaoning, China.
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Alguacil FJ, Robla JI. Transport of Chromium(VI) across a Supported Liquid Membrane Containing Cyanex 921 or Cyanex 923 Dissolved in Solvesso 100 as Carrier Phase: Estimation of Diffusional Parameters. MEMBRANES 2023; 13:177. [PMID: 36837680 PMCID: PMC9965649 DOI: 10.3390/membranes13020177] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 01/26/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
An investigation of chromium(VI) transport across a supported liquid membrane containing the phosphine oxides Cyanex 921 and Cyanex 923 dissolved in Solvesso 100 as carrier phases was carried out in batch operation mode. Chromium(VI) transport was investigated as a function of different variables: hydrodynamic conditions in the feed (1000-1600 min-1) and stripping (600-1500 min-1) phases, HCl (0.25-2 M) and indium (0.01-0.1 g/L) concentrations in the feed phase, and carrier (0.01 M-0.75 M) concentration in the membrane phase. Indium was recovered in the stripping phase using hydrazine sulphate solutions, and, at the same time, chromium(VI) was reduced to the less harmful Cr(III) oxidation state. Models describing the transport mechanism comprising a diffusion process through the feed aqueous diffusion layer, fast interfacial chemical reaction, and diffusion of the respective chromium(VI)-phosphine oxide complexes across the membrane were developed. The equations describing the rate of transport correlate the membrane permeability coefficient with diffusion and equilibrium parameters, as well as the chemical compositions of the respective metal-carrier phases. The models were used to calculate diffusional parameters for each metal-carrier system, and the minimum thickness of the feed boundary layer was calculated as 1 × 10-3 cm and 6.3 × 10-4 cm for the Cr(VI)-Cyanex 921 and Cr(VI)-Cyanex 923 systems, respectively.
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Coordination extraction for separating vanadium and impurities from black shale HCl leachate at low pH using D2EHPA and EHEHPA mixture. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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