Chromatographic Separation, Total Determination and Chemical Speciation of Mercury in Environmental Water Samples Using 4-(2-Thiazolylazo) Resorcinol-Based Polyurethane Foam Sorbent-Packed Column

A simple method has been developed for quantitative retention of traces of mercury(II) ions from aqueous media using polyurethane foams (PUFs) loaded with 4-(2-thiazolylazo) resorcinol (TAR). The kinetics and thermodynamics of the sorption of mercury(II) ions onto PUFs were studied. The sorption of mercury(II) ions onto PUF follows a first-order rate equation with k = 0.176 ± 0.010 min−1. The negative values of ΔH and ΔS may be interpreted as the exothermic chemisorption process and indicative of a faster chemisorption onto the active sites of the sorbent. The sorption data followed Langmuir, Freundlich and Dubinin-Radushkevich (D–R) isotherm models. The D-R parameters β, KDR and E were 0.329 mol2 kJ−2, 0.001 μmol g−1 and 1.23 ± 0.07 kJ/mol for the TAR-loaded PUFs, respectively. An acceptable retention and recovery (99.6 ± 1.1%) of mercury(II) ions in water at ≤10 ppb by the TAR-treated PUFs packed columns were achieved. A retention mechanism, involving absorption related to “solvent extraction” and an “added component” for surface adsorption, was suggested for the retention of mercury(II) ions by the used solid phase extractor. The performance of TAR-immobilized PUFs packed column in terms of the number (N), the height equivalent to a theoretical plate (HETP), the breakthrough and critical capacities of mercury(II) ion uptake by the sorbent packed column were found to be 50.0 ± 1.0, 1.01 ± 0.02 mm, 8.75 and 13.75 mg/g, respectively, at 5 mL/min flow rate

Green synthesis of mesoporous 2D Mn2O3/rGO nanocomposite for effective removal of methyl orange

Green synthesis of di-manganese trioxide mesoporous structure (super nano porous) sheets (Mn2O3-rGO-NS), Graphene oxide nano sheets (GO) and Mn2O3-rGO-NS nano sheets composite (Mn2O3-rGO-NS) were prepared via Thermal decomposition, seconds timescale water electrolytic oxidation and sonication method respectively. The prepared samples were characterized via X-ray diffraction, FESEM, TEM , and FTIR. Average crystallite size was found about 38 and 26 nm for Mn2O3-NS and Mn2O3-rGO-NS, respectively. Mn2O3-rGO–NPs morphology reveal nano porous sheets within average 35 nm and 26 nm in pores diameter and thickness respectively. Mn2O3-NS act distributed on and between graphene sheets creating macro and nano pores. The obtained results showed that the characteristics of the α-Mn2O3-rGO-NS sheets were improved by the addition of rGO sheets. Methyl orange (MO) dye adsorption onto Mn2O3-rGO-NS composite was investigated at various adsorption parameters, including pH, adsorbent quantity, and time. It was discovered that the adsorption behavior complies with the intra-particle diffusion model and the Friedendlich isotherm. Methyl orange in aqueous media may be eliminated 99.3% by Mn2O3-rGO-NS composite. HIGHLIGHTS Mesoporous graphene-based composite synthesis for dye removal from aqueous media with high efficiency and capacity. According to thermodynamics and kinetics adsorption is favorable, which opens up the possibility for further trials on various types of pollutant removal studies for the industry.

Green Synthetized Selenium Nanoparticles Using <i>Syzygium aromaticum</i> (Clove) Extract Reduce Pentylenetetrazol-Induced Epilepsy and Associated Cortical Damage in Rats

We aimed to investigate the potential anticonvulsant effect of green synthetized selenium nanoparticles (SeNPs) using Syzygium aromaticum extract (SAE) (SAE-SeNPs) against epileptic seizures and cortical damage induced by pentylenetetrazole (PTZ) injection in rats and its mechanism. A total of 84 rats were divided into six groups; control, PTZ-exposed group, SAE + PTZ-treated group, sodium selenite (Na2SeO3) + PTZ-treated group, SAE-SeNPs + PTZ-treated group, and diazepam + PTZ-treated group. SAE-SeNPs significantly increase (p p p p < 0.05) the PTZ-induced changes in the neurotransmitter norepinephrine level and acetylcholinesterase enzymatic activity. These data concluded the anticonvulsant activity of SAE-SeNPs via their antioxidant, anti-inflammatory, and anti-apoptotic effects, along with their ability to modulate neurotransmitters