Recent advances and applicable flexibility potential of electrochemical processes for wastewater treatment

This study examined >140 relevant publications from the last few years (2018-2021). In this study, classification was reviewed depending on the operation's progress. Electrocoagulation (EC), electrooxidation (EO), electroflotation (EF), electrodialysis (ED), and electro-Fenton (EFN) processes have received considerable attention. The type of action (individual or hybrid) for each electrochemical procedure was evaluated, and statistical analysis was performed to compare them as a new manner of reviewing cited papers providing a massive amount of information efficiently to the readers. Individual or hybrid operation progress of the electrochemical techniques is critical issues. Their design, operation, and maintenance costs vary depending on the in-situ conditions, as evidenced by surveyed articles and statistical analyses. This work also examines the variables affecting the elimination efficacy, such as the applied current, reaction time, pH, type of electrolyte, initial pollutant concentration, and energy consumption. In addition, owing to its efficacy in removing toxins, the hybrid activity showed a good percentage among the studies reviewed. The promise of each wastewater treatment technology depends on the type of contamination. In some cases, EO requires additives to oxidise the pollutants. EF and EFN eliminated lightweight organic pollutants. ED has been used to treat saline water. Compared to other methods, EC has been extensively employed to remove a wide variety of contaminants.

A selective hydrometallurgical method for scandium recovery from a real red mud leachate: A comparative study

The aim of this study was to recover Sc as the main product and Fe as a by-product from Hungarian bauxite residue/red mud (RM) waste material by solvent extraction (SX). Moreover, a new technique was developed for the selective separation of Sc and Fe from real RM leachates. The presence of high Fe content (∼38%) in RM makes it difficult to recover Sc because of the similarity of their physicochemical properties. Pyrometallurgical and hydrometallurgical methods were applied to remove the Fe prior to SX. Two protocols based on organophosphorus compounds (OPCs) were proposed, and the main extractants were evaluated: bis(2-ethylhexyl) phosphoric acid (D2EHPA/P204) and tributyl phosphate (TBP). The results showed that SX using diethyl ether and tri-n-octylamine (N₂₃₅) was efficient in extracting Fe(III) from the HCl leachate as HFeC1₄. Over 97% of Sc was extracted by D2EHPA extractant under the following conditions; 0.05 mol/L of D2EHPA concentration, A/O phase ratio of 3:1, pH 0-1, 10 min of shaking time, and a temperature of 25 °C. Sc(OH)₃ as a precipitate was efficiently obtained by stripping from the D2EHPA organic phase by 2.5 mol/L of NaOH with a stripping efficiency of 95%. In the TBP system, 99% of Sc was extracted under the following conditions: 12.5% vol of TBP, an A/O phase ratio of 3:1, 10 min of shaking time, and a temperature of 25 °C. The Sc contained in the TBP organic phase could be efficiently stripped by 1 mol/L of HCl with a stripping efficiency of 92.85%.

[Comparison of serum concentrations of caffeine, 4-methylaminoantipyrine, sulfamethazine and debrisoquin following oral administration of these substances as a cocktail in type II diabetics before and after insulin therapy]

A cocktail of 4 substances (caffeine/CYP1A/CYP1A2, metamizol/CYP2B, debrisoquin/CYP2D6 and sulfamethazine/N-acetyltransferase) was administered to 15 maturity-onset diabetics before and 6 months after insulin therapy (IT) to examine changes in hepatic biotransformation capacity in humans under pathological conditions. Blood and urine samples were taken 6 h after oral administration of the drugs. There were no differences in acetylation- and hydroxylationsphenotyping before or during IT. However, a significant increase in concentration of free sulfamethazine during IT can be interpreted as induction of N-acetyltransferase by poor metabolic control. Comparison of caffeine-concentration showed no significant differences. Obviously in humans CYP1A2 is not influenced by type-II-diabetes mellitus. Concentration of 4-methyl-antityprine (4-MAA), a metabolite of metamizol, was significantly increased during IT. This results shows a possible induction of CYP2B by poor metabolic control.