Heavy metals can cause serious environmental and human health problems, and their removal from wastewater is critical to protect our planet and communities. This study investigated the ability of crushed pomegranate peel to remove mercury and cadmium ions from contaminated water as a function of different experimental parameters. The experimental results showed that the pH of the solution influenced the adsorptive removal of heavy metals, with the best performance observed at pH 4.8. Optimization studies and process balance modeling were performed to optimize the process for commercial use. The performance of pomegranate peel was compared with that of other materials, and the highest adsorption capacities for both cadmium (Ca (II)) and mercury (Hg (II)) ions were observed to be 89.59 and 42.125 mg/g, respectively. The results were interpreted using the Langmuir model, which provided the best fit to describe the behavior of the process.

BACKGROUND: Liquid crystal monomers (LCMs) have been classified as emerging organic pollutants. Efficient isolation and extraction is a critical step in the determination, and then knowing the occurrence and distribution of LCMs in environmental waters. However, the reported sample preparation techniques still suffer some dilemmas such as using large amount of organic solvent, low extraction capacity, tedious operation procedure and employment of expensive extraction column. To circumvent the disadvantages, new extraction format and adsorbent with quickness, less consumption of organic solvent, superior extraction performance and low cost should be developed for the analysis of LCMs.
RESULTS: Using 1H,1H,2H,2H-heptadecafluorodecyl acrylate and 9-vinylanthracene as mixed functional monomers, a task specific magnetic adsorbent (TSMA) was prepared by one-pot hydrothermal technique for the highly efficient capture of LCMs under magnetic solid phase extraction (MSPE) format. Due to the abundant functional groups, the developed TSMA/MSPE presented satisfactory capture performance towards LCMs. Satisfactory enrichment factors (132-212) and high adsorption capacity (18 mg/g) were obtained. Additionally, the relevant adsorption mechanism was studied by the combination of density functional theory calculation and experiments about adsorption kinetics and adsorption isotherm. Under the beneficial conditions, a sensitive and reliable method for the monitoring of studied LCMs in environmental waters was established by the combination of TSMA/MSPE with HPLC equipped with diode array detector (DAD). The achieved limits of detection and spiked recoveries were 0.0025-0.0061 μg/L and 81.0-112 %, respectively. Finally, the developed method was employed to monitor LCMs levels in the North Creek watershed of Jiulong River.
UNASSIGNED: The current study provided a new adsorbent for quick and efficient capture of LCMs at trace levels. In addition, a sensitive, reliable and anti-intereference method for the monitoring of trace LCMs in actual waters was established. Moreover, for the first, the contents, occurrence and distribution of LCMs in North Creek watershed was investigated based on the developed method.

The successful adoption and widespread implementation of innovative acid mine drainage treatment and resource recovery methods hinge on their capacity to demonstrate enhanced performance, economic viability, and environmental sustainability compared to conventional approaches. Here, an evaluation of the efficacy of chromium-based metal-organic frameworks and amine-grafted SBA15 materials in adsorbing europium (Eu) from actual mining wastewater was conducted. The adsorbents underwent comprehensive characterization and examination for their affinity for Eu. Cr-MIL-PMIDA and SBA15-NH-PMIDA had a highest Langmuir adsorption capacity of 69 mg/g and 86 mg/g, respectively, for an optimum level of pH 4.8. Preferential adsorption tests followed using real AMD collected at a disused mine in the north of Norway. A comparative study utilizing pH-adjusted real AMD revealed that Cr-MIL-PMIDA (88%) exhibited slightly higher selectivity towards Eu compared to SBA15-NH-PMIDA (81%) in real mining wastewater. While Cr-MIL-PMIDA displays excellent properties for the selective recovery of REEs, practical challenges related to production costs and potential susceptibility to chromium leaching make it less appealing for widespread applications. A cost-benefit analysis was then undertaken to quantify the advantages of employing SBA15-NH-PMIDA material. The study disclosed that 193.2 g of EuCl3 with 99% purity can be recovered by treating 1000 m3 of AMD.

The textile industry is discharging high concentrations of anionic and cationic azo dyes into the nearby environment, which can cause adverse effects on public health, and the aquatic environment. Therefore, this study aimed to develop giant reed biochar and apply for the removal of Basic blue 41 (BB41) and Eriochrome black T (EBT) azo dyes from water. Characterization techniques such as BET surface area analyzer, Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermal gravimetric analyzer (TGA) were applied for biochar description. The biochar exhibits a high fixed carbon content (80.4%), a low ash content (3.8%), a large surface area (429.0 m2/g), and good thermal stability. High removal efficiencies of BB41 98.6% and EBT 82.5% were recorded at the specific experimental condition. The experimental data were fitted with the Langmuir isotherm model at R2 0.99 for both dyes whereas the adsorption kinetics revealed the pseudo-second-order kinetics at R2 ∼ 1 and 0.99 for BB41 and EBT, respectively. Furthermore, four regenerations of biochar with adsorption performances of BB41 and EBT dyes were found to be 94.7% and 79.1%, respectively. Finally, this adsorbent can be considered an economically viable material for the removal of synthetic dyes from wastewater systems. In conclusion, the study findings showed that the adsorbent material is promising to apply for water and wastewater treatment but still, the study of adsorption interaction and modifications of the surface functionalities are essential to accommodate multipollutant removal from real water systems.

Gac fruit (Momordica cochinchinensis Spreng.) is a prominent source of carotenoids, renowned for its exceptional concentration of these compounds. This study focuses on optimizing the extraction of active components from the aril of gac fruit by evaluating the effects of extraction temperature, solid-liquid ratio, and extraction time. The primary objective is to maximize the yield of gac oil while assessing its antioxidant capacity. To analyze the kinetics of the solid-liquid extraction process, both first-order and second-order kinetic models were employed, with the second-order model providing the best fit for the experimental data. In addition, the potential of gac fruit peel as a precursor for biochar production was investigated through carbonization. The resultant biochars were evaluated for their efficacy in adsorbing crystal violet (CV) dye from aqueous solutions. The adsorption efficiency of the biochars was found to be dependent on the carbonization temperature, with the highest efficiency observed for BCMC550 (91.72%), followed by BCM450 (81.35%), BCMC350 (78.35%), and BCMC250 (54.43%). The adsorption isotherm data conformed well to the Langmuir isotherm model, indicating monolayer adsorption behavior. Moreover, the adsorption kinetics were best described by the pseudo-second-order model. These findings underscore the potential of gac fruit and its byproducts for diverse industrial and environmental applications, highlighting the dual benefits of optimizing gac oil extraction and utilizing the peel for effective dye removal.

In the present study, activated carbon (AC), activated carbon/hydroxyapatite (AC/HAp), and carboxymethyl cellulose/activated carbon/hydroxyapatite (CMC/AC/HAp) composite adsorbents were prepared to remediation of methylene blue (MB) from water media. The pyrolysis method used the Pine cone as a natural precursor to synthesize AC. FTIR, XRD, Raman, BET, TEM, and SEM-Dot mapping techniques were applied to characterize synthesized adsorbents. Experimental results demonstrated that the maximum removal efficiency of AC, AC/HAp, and CMC/AC/HAp adsorbents under optimum conditions of pH 8, adsorbent dose 1 g/L, contact time 60 min, initial concentration 10 mg/L, and temperature 25 °C was computed to be 98.75, 98.86, and 98.93 %, respectively. Kinetic and equilibrium data were well-fitted with pseudo-second-order and Langmuir models, respectively. The maximum monolayer adsorption capacity of AC, AC/HAp, and CMC/AC/HAp was determined to be 40, 44.248, and 43.86 mg/g, respectively. FTIR results showed that hydrogen bonding and electrostatic interactions are the main mechanisms of the adsorption process. Results of the thermodynamic study showed that the adsorption process is spontaneous and exothermic. Finally, AC, AC/HAp, and CMC/AC/HAp composite adsorbents can be used as promising adsorbents for the remediation of MB from wastewater.

Pimelea poisoning of cattle causes distinct symptoms and frequently death, attributable to the toxin simplexin. Pimelea poisoning was induced via addition of ground Pimelea trichostachya plant to the daily feed in a three-month trial with Droughtmaster steers. The trial tested four potential mitigation treatments, namely, biochar, activated biochar, bentonite, and a bacterial inoculum, and incorporated negative and positive control groups. All treatments tested were unable to prevent the development of simplexin poisoning effects. However, steers consuming a bentonite adsorbent together with Pimelea showed lesser rates-of-decline for body weight (P < 0.05) and four hematological parameters (P < 0.02), compared to the positive control group fed Pimelea only. Microbiome analysis revealed that despite displaying poisoning symptoms, the rumen microbial populations of animals receiving Pimelea were very resilient, with dominant bacterial populations maintained over time. Unexpectedly, clinical edema developed in some animals up to 2 weeks after Pimelea dosing was ceased.

Globally, the release of greenhouse gases primarily carbon dioxide (CO2) emissions to our Earth\'s surface has climbed by  about 45% to its present atmospheric concentration rate of 420 parts per million (ppm) during the industrial era. An unprecedented rise in atmospheric CO2 concentration has been claimed to lead to significant factors such as global warming potential (GWP) and climate change effects.  An increase in atmospheric CO2 concentrations is  a  serious threat to the environment. Recent research efforts have focused on mitigating emissions from anthropogenic point sources. Adsorption-based post-combustion CO2 capture using solid adsorbents is the most effective and efficient method for mitigating gas adsorption in the exhaust system. In the current study, activated carbons are obtained from three potential biomass, namely, (i) coconut shell, (ii) rice husk, and (iii) eucalyptus wood, through a - single-stage activation method. The prepared activated carbon materials are analyzed using proximate and ultimate analyses. Further investigations are performed using different characterization techniques to ensure their adsorption efficiency. Adsorbents are packed one after the other in an in-house fabricated double adsorption chamber and coupled to the exhaust unit of a generator. Test experiments are conducted to examine adsorbents\' capture efficiency in emissions mitigation. Adsorbents\' adsorption parameters are evaluated in experimental investigations. At 2.5 bar and 50 °C, a maximum loading capacity of samples is achieved by 4.85 mmol/g, 4.58 mmol/g, and 5.96 mmol/g for coconut shell, rice husk, and eucalyptus wood adsorbents, respectively. With a post-combustion carbon adsorption chamber, CO2 and NO are captured about 40-64% and 38-58%, respectively, for all three adsorbents. The thermodynamic parameter of isosteric heat of adsorption value is below 40 kJ/mol, ensuring physisorption for all adsorbents.

Environmental sustainability has gained acceptance to achieving the goal of a secure ecosystem with a reliable management system. Heavy metal remediation of aqueous streams is of special concern due to the intractability and persistence in the environment. Adsorption is a potential alternative to the existing inefficient conventional technologies for the removal and recovery of metal ions from aqueous solutions and becomes vital to align with the Sustainable Development Goals (SDGs) and mitigate the adverse environmental and social impacts. Calcium Alginate-Graphene oxide (CA-GO) composite has been synthesized for the adsorption of heavy metals including Cr3+, Cu2+, and Cd2+ ions from tannery effluents. Graphene oxide is prepared from commercial graphite powder and reacted with sodium alginate and calcium chloride to form the beads of CA-GO composite. The developed composite was characterized by FTIR, elemental analysis, SEM, XRD analysis, and Raman spectroscopy. Moreover, the effect of pH, adsorbent dosage, contact time, and initial concentration of metal ions on the adsorption capacity were investigated through batch experiments. At a pH>3.0 (pHzpc), the carboxyl group of CA-GO was deprotonated to make the surface negatively charged and facilitate metal adsorption. The optimum pH and maximum adsorption capacity of CA-GO for removal of Cr(III), Cu(II), and Cd(II) were 4.5, 6.0, and 7.0, and 90.58, 108.57, and 134.77 mg g-1, respectively. The kinetics, adsorption isotherms, and thermodynamics were studied to determine the adsorption mechanism. The kinetic of adsorption adopted the second-order model. Thermodynamic parameter were calculated and the adsorption process was determined to be exothermic and spontaneous at room temperature. The developed composite has been efficaciously applied for the removal of metal ions and pollution from real tannery effluents.

Untreated tannery wastewater contains a large amount of toxic metals, dyes, and other pollutants, which pose adverse effects on the ecosystem and public health. In this work, a calcium alginate-poly vinyl alcohol-graphene oxide (CA-PVA-GO) composite was prepared to remove metals and dyes, particularly Cr(Ⅲ) and CI acid violet 54 (AV54) dye, from tannery wastewater. FESEM, FTIR, and XRD analyses were applied to characterize the GO and CA-PVA-GO. Different operational variables, viz. pH (3.0-5.5 for Cr(III) and 2-7 for dye), dosage (0.164-2.46 g/L), contact time (10-60 min), initial concentration (39, 65, 98, and 201 ppm for Cr(III) and 21.5, 38.5, 54.5, and 61.75 ppm for dye), and temperature (298, 308, 318, and 328 K) were studied to evaluate the efficiency of the CA-PVA-GO composite. The optimum conditions for Cr(Ⅲ) and AV54 dye adsorption were found to be pH (5.0 and 3.0), dosage (0.82 g/L for both), and time (45 and 60 min), respectively, with 35.35 ± 1.43% and 84.63 ± 2.54% removal efficiency. The experimental data was analyzed through the Langmuir and Freundlich isotherms. The maximum adsorption capacity (qm) was observed at 173.01 and 74.68 mg/g for Cr(Ⅲ) and AV54 dye, respectively. The pseudo-second-order kinetic model was fitted better (R2 = 0.981, 0.995, 0.92, and 0.995) than first-order for AV54 dye adsorption. Thermodynamic analyses revealed that the Cr(Ⅲ) and AV54 dye adsorption processes were spontaneous and exothermic. The value of Gibbs free energy (ΔG) for Cr(III) adsorption was obtained at -7.433, -4.508, -2.626, and -1.311 kJ/mol, whereas it was -5.178, -4.867, -4.628, and -4.555 kJ/mol for dye. The values of ΔH and ΔS were -67.257 and -0.198 kJ/mol for Cr(III) and -10.852 and -0.019 kJ/mol for the dye removal. The regenerated CA-PVA-GO composite was reused successfully. Different physicochemical parameters, viz., concentration, pH, TDS, EC, BOD5, and COD of chrome tanning and dyeing effluents, were analyzed before and after the adsorption. The results of chromium and dye removal from tannery wastewater were 53.18% and 93.91%, revealing that the developed eco-friendly CA-PVA-GO composite could be an operative adsorbent for tannery wastewater treatment and possibly scaled up to an industrial level.