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Due to its high toxicity and mobility, hexavalent chromium must be adequately eliminated from effluent or wastewater. For Cr(VI) adsorption, it is increasingly becoming customary to use inexpensive, readily accessible plant-based materials. It has been discovered that the popular medicinal herb Simarouba glauca is quite effective at removing Cr(VI) from aqueous media. The first stage of this study examines Cr(VI) adsorption onto S. glauca using the 25 Full Factorial Design technique. It was possible to determine the major effects of S. glauca dosage and how they interacted with pH, temperature, the initial Cr(VI) concentration, and time. The adsorption was predicted adequately with the aid of ANOVA, t-test, Pareto charts, main effect, and interaction plots. The second section of the study focuses on the potential for continuous adsorption of S. glauca in a fixed-bed column. The Cr(VI) inlet concentration (50, 100 and 150 mg/L), flow rate (13 and 21 mL/min), and S. glauca bed height (30, 36, 40 and 45 cm) all had an impact on the breakthrough qualities of the adsorption system. The fixed-bed adsorption models of Thomas, Yoon–Nelson, and Adams-Bohart were used to fit the adsorption data. The Thomas model, with a flow rate of 13 mL/min, a bed height of 45 cm and an inlet concentration of 100 mg/L of Cr(VI), calculated the adsorption capacity to be 611.6 mg/g with a coefficient of 0.99. The findings are consistent with the hypotheses advanced by Thomas and Yoon–Nelson. This study suggests that this technique could be used to treat chromium-contaminated water in industrial settings. [ABSTRACT FROM AUTHOR]

Rice, wheat, and maize grains are staple foods, widely consumed for their mineral and nutritional values. However, they can accumulate toxic elements from contaminated soils, posing health risks. This study investigates the bioaccumulation patterns of 52 elements (including nutrients, heavy metals, and rare earth elements) in various parts (grain, husk, straw, and root) of cereals grown in a heavily polluted region. The results revealed that rice grains exhibited a higher accumulation (Σ33.4 mg/kg) of toxic elements (As, Cu, Cr, Ni, and Pb) than wheat (Σ26.6 mg/kg) and maize (Σ16.2 mg/kg) grains, with the high-yield RI64 cultivar (Σ47.0 mg/kg) being the most susceptible. Across the rice plant, accumulation increased in the order of grain < husk < straw < root. Elements like P, K, Cu, and Zn showed the highest enrichment. Worryingly, the most toxic elements, such as As, Pb, and Cd, exceeded permissible limits across grains, straws, and husks. Health risk assessment indicated that wheat and maize pose greater non-cancer and cancer risks than rice. Despite being grown in a highly contaminated region, the study identifies some rice cultivars like Luchai and Sarna as relatively safer options due to a lower accumulation of toxic elements. [ABSTRACT FROM AUTHOR]

Most coal in India originates from the Korb basin (Chhattisgarh), where coal mines, thermal power, and aluminum plants operate. Groundwater in this region faces severe pollution due to land reclamation, leaching of coal‐related contaminants, waste disposal, and industrial effluent seepage. This work presents results from monitoring groundwater pollution in the Korba basin from 2012 to 2017. Fluoride, aluminum, manganese, and iron levels exceeded acceptable quality limits across all 28 studied locations, with excessive nitrate, magnesium, calcium, and lead levels in specific sites. Tracking seasonal and temporal fluctuations in the most polluted site, namely Kudurmal, revealed peak solute concentrations during the monsoon period and a sustained 18% increase during the study period. Factorial analysis suggests groundwater contamination arises from both human activities and natural sources. These findings underscore the urgent necessity of devising remediation strategies for the drinking water supply. [ABSTRACT FROM AUTHOR]

Several million tons of coal are extracted which discharge the contaminated mineral water into the environment in the coal mines located in the Korba basin (Chhattisgarh, India) chosen as the study area. The aim of this work is to describe: (i) the physico‐chemical characteristics (pH, EC, TDS, DO, RP, CC (carbonate carbon), OC (organic carbon) F−, Cl−, NO3−, SO42−, SiO44−, PO43−, Na+, K+, Mg2+, Ca2+, Al, As, Sb, Fe, Mn, Zn, Cd, Pb, and Hg) of the coal mine water samples, (ii) spatial, seasonal (i.e. PrM (pre‐monsoon), M (monsoon) and PtM (post monsoon) and temporal (over the period of 2012–2017) variations, (iii) sources of contaminants from fourteen coal mines, (iv) suitability of the water for drinking and other uses, and (v) health impact of the mine water in view of developing remedial approaches. The mine water is neutral in nature with high TDS (total dissolved solid) values ranging from 620 to 13711 mg L−1 due to mainly high carbon content. The concertation of all species lies between 519–11432 mg L−1 with maximum value of OC. The most dominating species were OC, CC, Cl−, NO3−, SO42−, Na, and Ca. Species, that is, F−, OC, Al, Fe, As, Sb, Cd, Pb, and Hg occurred beyond their limits. Their higher concentration in the PtM is observed. Water quality index (WQI) values ranged from 17.52 to 95.68 in the PtM period. 42.85%, 21.42%, and 7.14% of water samples represent "excellent water", "good water" and "poor water" respectively in the PtM period. In addition, the fertilizer and trace element concentrations in the water samples were compared with the limit values determined for usability as drinking water. Accordingly, it was concluded that it is not suitable for use as drinking water in terms of TDS, F−, and NO3− concentrations. In addition, AsT (total arsenic), F− and NO3− pollutants were detected in the water samples, and it was observed that F− and NO3− ions did not have a carcinogenic effect. A health risk assessment of As has been made, and it is found that adults and children have a low risk of developing cancer from the exposure. However, arsenic has high non‐carcinogenic and potentially harmful effects. [ABSTRACT FROM AUTHOR]

Pseudo-first-order rate constants for the nucleophilic debenzoylation reaction of p-nitrophenyl benzoate with various hydroxamate ions [RC = ONHO-] were investigated in aqueous cationic micellar media at pH 7.8 and 27°C. The kinetic rate data of the reaction revealed that the nucleophilic reactivity sequence of these hydroxamate ions is generally benzohydroxamic acid > salicylhydroxamic acid > acetohydroxamic acid. The kobs value increases upon addition of cationic surfactants to the reaction medium involving interfacial ion exchange between bulk aqueous media and micellar pseudophase. The effect of surfactant head and tail group is discussed. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 42: 106–112, 2010 [ABSTRACT FROM AUTHOR]

The objective of the present work was to investigate the removal of Ni(II) by the fresh biomass (FBM) and chemically treated leached biomass (LBM) of Calotropis procera. The scope of the work included screening of the biosorbents for their metal uptake potential, batch equilibrium, column mode removal studies and kinetic studies at varying pH (2-6), contact time, biosorbent dosages (1-25 g/L) and initial metal ion concentration (5-500 mg/L). The development of batch kinetic model and determination of order, desorption studies, column studies were investigated. It was observed that pH had marked effect on the Ni(II) uptake. Langmuir and Freundlich models were used to correlate equilibrium data on sorption of Ni(II) metallic ion by using both FBM and LBM at 28 degrees C and pH 3 and different coefficients were calculated. It was found that both biomasses were statistically significant fit for Freundlich model. The biomass was successfully used for removal nickel from synthetic and industrial effluents and the technique appears industrially applicable and viable.