Electrocatalytic removal of fluroquinolones from simulated pharmaceutical effluent: Chemometric analysis, chemical blueprint of electrodes and generated sludge

UiO-66 octahedrons for adsorptive removal of direct blue-6: process optimization, interaction mechanism, and phytotoxicity assessment

The materials for water treatment have been evolving in multitude of dimensions, indicating the importance of water reuse and increasing level of water pollution around the globe. Among the various materials that are utilized in wastewater treatment, the material that has attracted the research community for the past decades is the metal organic framework (MOF). In this work one of the water stable and microporous MOF, UiO-66, and its aminated version has been employed to adsorb an anionic azo dye, direct blue-6 (DB-6), from the aqueous matrix. Performance of both the MOFs was compared to know the efficiency under varying solution conditions. The optimized parameters for DB-6 adsorption by UiO-66 was performed using response surface methodology. This numerical optimization was further extended with canonical and ridge analysis. Under optimal conditions, the materials were exhibiting a good adsorption capacity of 754.4 mg/g. The materials were analyzed in terms of morphology, crystallinity, thermal stability, and surface area using instruments like X-ray diffraction, electron microscopy, thermogravimetric analysis, and BET surface area analysis. The mechanism of interaction between UiO-66 and DB-6 molecule was elucidated with the help of XPS analysis which helps to know the main interacting group of UiO-66. This study was concluded with a phytotoxicity analysis of DB-6 and the antioxidant system of Vigna radiata assessed using pre and post adsorbed water.

Sequestration and toxicological assessment of emerging contaminants with polypyrrole modified carboxymethyl cellulose (CMC/PPY): Case of ibuprofen pharmaceutical drug

Ibuprofen (IBU) is a non-steroidal anti-inflammatory drug released into water bodies causing toxic biological effects on living organisms. The current study aims to eliminate IBU from aqueous solutions by a novel carboxymethylcellulose/polypyrrole (CMC/PPY) composite with high removal efficiency. Pyrrole was polymerized to polypyrrole whose average size was about 20 nm on the CMC surface. The maximum removal percentage of IBU by CMC/PPY composite was optimized at initial concentration 10 mg/L, dosage 0.02 g, and pH 7 with adsorption capacity of 72.30 (mg/g) and removal of 83.17 %. IBU adsorption onto CMC/PPY theoretically fits into the Langmuir isotherm and Elovich-kinetic models. Fish and Phytotoxicity assessment were performed with zebrafish and seeds of Vigna mungo (VM) and Vigna radiata (VR). The toxicity study reveals that before adsorption, IBU shows high toxicity towards the zebrafish mortality (33 %), growth inhibition (58.52 % for VM, 60.84 % for VR), and germination (86.66 % for VM and 90 % for VR). As CMC/PPY adsorbs IBU, toxicity drastically decreases. Before adsorption, LC₅₀ was 233.02 mg/L. After adsorption, the LC₅₀ increases to 2325.07 mg/L as IBU molecules get adsorbed by CMC/PPY. These findings show the feasibility of preparing CMC/PPY composite to effectively remove pharmaceutical pollutant IBU from aqueous solutions with their toxicological assessment.

New research on water, waste and energy management, with special focus on antibiotics and priority pollutants

The Editors of the Virtual Special Issue (VSI) "New Research on Water, Waste and Energy Management, with Special Focus on Antibiotics and Priority Pollutants" (VSI WWEM-20) here present details corresponding to papers that have been accepted, as well as further comments on the matter. It should be noted that the VSI should be associated to a Conference that had been initially programmed to be held in Rome during the summer of 2020, Unfortunately, it was postponed due to the COVID-19 pandemic. That conference was one of those within the series called "International Congress on Water, Waste and Energy Management". Although the Conference was postponed, the Call for Papers for the VSI was maintained by this journal. As a result, a set of very interesting papers were accepted after a careful peer-review process. We hope that it will be complemented with additional VSIs associated to future conferences corresponding to the series, increasing the knowledge on the topic.