Supported liquid membrane incorporated with carbon nanotubes for the extraction of Europium using Cyanex272 as carrier

Microbial strategies for copper pollution remediation: Mechanistic insights and recent advances

Environmental contamination is aninsistent concern affecting human health and the ecosystem. Wastewater, containing heavy metals from industrial activities, significantly contributes to escalating water pollution. These metals can bioaccumulate in food chains, posing health risks even at low concentrations. Copper (Cu), an essential micronutrient, becomes toxic at high levels. Activities like mining and fungicide use have led to Copper contamination in soil, water, and sediment beyond safe levels. Copper widely used in industries, demands restraint of heavy metal ion release into wastewater for ecosystem ultrafiltration, membrane filtration, nanofiltration, and reverse osmosis, combat heavy metal pollution, with emphasis on copper.Physical and chemical approaches are efficient, large-scale feasibility may have drawbackssuch as they are costly, result in the production of sludge. In contrast, bioremediation, microbial intervention offers eco-friendly solutions for copper-contaminated soil. Bacteria and fungi facilitate these bioremediation avenues as cost-effective alternatives. This review article emphasizes on physical, chemical, and biological methods for removal of copper from the wastewater as well asdetailing microorganism's mechanisms to mobilize or immobilize copper in wastewater and soil.

Effect of hydrophobic and hydrophilic nanoparticles loaded in D2EHPA/M2EHPA - PTFE supported liquid membrane for simultaneous cationic dyes pertraction

Cationic dyes mixture pertraction experiments of Rhodamine B (RhB) and Methylene Blue (MB) using a flat sheet supported liquid membrane (SLM) were performed. Mono-(2-etylhexyl) ester of phosphoric acid (M2EHPA) and bis-(2-etylhexyl) ester of phosphoric acid (D2EHPA) mixture was used as carrier and Sesame oil to dilute the carrier due to its very high viscosity. Acetic acid (AA) was also used as stripper phase. Influences of hydrophobic and hydrophilic nanoparticles were loaded in a carrier at different loadings (from 0 to 6 mg mL^-1) on dyes pertraction at constant operating conditions were investigated. It was found that hydrophilic nanoparticles, including ZnO and TiO₂ decrease dyes pertraction, while hydrophobic nanoparticles, including ZIF-8 and Fe₃O₄ favorably increase this parameter. ZIF-8 was found as the most effective nanoparticles on increasing dyes pertraction and the optimum loading was 2 mg mL^-1. Also, the important process parameters that influence on the dyes mixture pertraction efficiency such as feed concentration, carrier concentration, feed pH and strip concentration were studied. In order to investigate the effects of operating parameters, all experiments were performed at a constant 2 mg mL^-1 ZIF-8 loading. Optimum pertraction efficiency of RhB and MB were 90.6 and 79.4%, respectively. They were obtained after 10 h pertraction at optimum experimental conditions with feed concentration of 100 mg L^-1, carrier concentration of 35% (vol), strip concentration of 0.5 mol L^-1, and feed pH of 6. Effect of time on pertraction efficiencies at the optimum conditions were also studied.

Performance evaluation of hollow fiber renewal liquid membrane for extraction of uranium(VI) from acidic sulfate solution

The performance of the hollow fiber renewal liquid membrane (HFRLM) in the continuous and recycling modes for the extraction of uranium(VI) from the acidic sulfate solution has been investigated. Alamine 336 diluted in kerosene was used as a carrier in liquid membrane (LM) phase. In the batch experiments, the effects of sulfuric acid, extractant and uranium(VI) concentration were studied and the optimum concentration of the donor and LM phases were determined 0.15 mol L−1and 0.0125 mol L−1, respectively. Various parameters affecting the HFRLM performance including the lumen and shell side flow rate, organic/aqueous volume ratio, acceptor phase type and concentration of carrier and acceptor phase were studied. The mass transfer flux increases with increasing the lumen side flow rates and the shell side flow rate did not have any significant effect. The uranium transfer flux increases with increasing O/A ratio, acceptor and Alamine 336 concentration, and reaches a maximum value at 1/20, 0.5 mol L−1and 0.0125 mol L−1, respectively. Further increase in these parameters result in uranium transfer decrement. The results show that liquid membrane phase is a rate-controlling step. Among the investigated acceptor phases, 0.5 mol L−1NH4Cl result in 60.35% uranium(VI) recovery in the recycling mode.