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This work involved the preparation of pristine and iron nanoparticle-loaded biochar from a water chestnut shell to remove diclofenac sodium (DCF) containing effluent of pharmaceutical origin. To create suitable forecasting equations for the modelling of the DCF adsorption onto the adsorbent, response surface methodology (RSM) was used. The parameters, e.g. pH, adsorbent mass, DCF concentration and contact time, were used for the modeling of adsorption. The RSM model predicts that for 98.0% DCF removal, the ideal conditions are pH 6, an adsorbent dose of 0.5 g L−1, and a contact time of 60 min with an initial adsorbate concentration of 25 mg L−1 at 303 K. The maximum capacity deduced from the Langmuir model was 75.9 mg g−1 for pristine water chestnut shell biochar (pWCBC) and 122.3 mg g−1 for magnetically modified nano-Fe2O3 biochar (mWCBC). Under equilibrium conditions, the Langmuir model was the best-suited model compared to the Temkin and Freundlich models. The adsorption data in this investigation efficiently fitted the pseudo-second-order model, emphasizing that chemisorption or ion exchange processes may be involved in the process. The WCBC demonstrated recyclability after 10 cycles of repeated adsorption and desorption of DCF. A combined coagulation adsorption process removed COD, NH3–N, NO3−, PO43−, and DCF by 92.50%, 86.41%, 77.57%, 84.54%, and 97.25%, respectively. This study therefore shows that coagulation followed by adsorption onto biochar can be a cost-effective substitute for conventional pharmaceutical wastewater treatment. [ABSTRACT FROM AUTHOR]

The pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people and claimed thousands of lives. Starting in China, it is arguably the most precipitous global health calamity of modern times. The entire world has rocked back to fight against the disease and the COVID-19 vaccine is the prime weapon. Even though the conventional vaccine development pipeline usually takes more than a decade, the escalating daily death rates due to COVID-19 infections have resulted in the development of fast-track strategies to bring in the vaccine under a year’s time. Governments, companies, and universities have networked to pool resources and have come up with a number of vaccine candidates. Also, international consortia have emerged to address the distribution of successful candidates. Herein, we summarize these unprecedented developments in vaccine science and discuss the types of COVID-19 vaccines, their developmental strategies, and their roles as well as their limitations.

In this research study, a new bio adsorbent has been developed by synthesis of zirconium nanoparticles using Zingiber officinale rhizome extract and its subsequent entrapment in calcium alginate-carrageenin hydro gel beads. The characterisation of synthesised nanoparticles were carried out using SEM, TEM, SAED, EDAX and FT-IR. The resulting Zr-alginate-carrageenin, hydrogel beads were further subjected to batch sorption studies. Various physicochemical parameters such as pH, contact time, biomass doses were optimised for maximum removal of fluoride from aqueous solution. Results revealed that composite so prepared could remove fluoride from aqueous solution up to 98.5%.The equilibrium study has been carried out to investigate the capacity of adsorption by applying the Langmuir and Freundlich model, respectively. The nature of adsorption was found to be endothermic, spontaneous and belonged to chemisorption as supported by Temkin and D-R isotherm studies. [ABSTRACT FROM AUTHOR]

The tannery industry influences the gross domestic product/economic activity of any country, but the uncontrolled release of tannery effluents causes environmental degradation and increases health risks to human. The reason for the toxicity of tannery effluents is the presence of high concentrations of organic and inorganic chemicals used in the production of leather goods. Untreated or partially treated effluents discharged into surface water results in an increase in both chemical and biological oxygen demand as well as in an increase in the levels of total suspended solids, dissolved solids, and toxic metals in environmental bodies, especially in soil, water bodies, and water sediments. Various treatment techniques, such as physicochemical, biological, and advanced oxidation methods, which include chemical precipitation, electrocoagulation, aerobic or anaerobic treatment, wetland construction, and Fenton, electro‐Fenton, and photo‐Fenton processes are also described. This review also discusses the technical appropriateness and economic feasibility of reducing the effluent pollution load and solid waste emanating from the tannery industry. Considering the enhanced health risks in the tannery waste treatment and management regime, some green and advanced technologies should be explored. A sustainable green technology that avoids the use of toxic chemicals in the tanning process is seen well for ecological health. [ABSTRACT FROM AUTHOR]

Arsenicosis, due to consumption of an elevated amount of arsenic‐containing groundwater is a serious issue related to human health. The ubiquitous nature of arsenic is also a part of agricultural soil solution and its uptake by edible plants imposes a considerable human health risk. A calcium pretreated wood of Moringa oleifera was pyrolyzed and converted into biochar. The resultant biochar was examined for arsenite and arsenate uptake from an aqueous solution. Further, characterization of biochar was performed using Fourier transformed infrared spectroscopy (FT‐IR) and Scanning electron microscope with energy dispersive x‐ray (SEM‐EDAX) analysis. Results suggested the involvement of different functional groups of calcium‐modified biochar in As(III) and As(V) sorption processes. Experimental data of batch sorption revealed that CaMBC could adsorb analyte ions from pH 5.0 to 7.0 with maximum percentage removal, that is, 87.27 and 94.52% at adsorbent concentration 2 g/L. A high loading capacity of prepared adsorbent was found to be 37.22 mg/g for arsenate and 33.44 mg/g for arsenite ions. The sorption occurred due to chemical interaction between functional group and arsenic ions, which existed over the surface of prepared biochar. The spontaneous sorption makes a CaMBC, an ideal candidate for the removal of dissolved arsenite, arsenate ions. [ABSTRACT FROM AUTHOR]

The present study reports a benign approach to prepare citrate capped iron particles using juice of a lemon fruit. Resultant particles were subjected to detailed adsorption studies for removal of arsenite aqueous solution of defined concentration. The planer reflection of XRD analysis suggested that iron particles were crystalline in nature. FT-IR study suggested that functional groups like -NH2, -NO2, -CO, and --CS were involved in arsenite ion sorption. The composite removal efficiency for As (III) was found to be 88.58%, at pH 4.5, with contact time of 30 min and temperature at 30°C. Data of adsorption were analyzed using various parameter like isotherm models, thermodynamic and kinetic models. Chemisorptions resulted in to formation of monolayer arsenite ions over the surface of prepared iron particles with maximum adsorption capacity; 55.53 mg/gm. Adsorbent hold good promises to remove arsenic from contaminated water. [ABSTRACT FROM AUTHOR]

In the present research work, removal of fluoride from aqueous solution using fenugreek leaf mediated Zr nanoparticle entrapped in calcium alginate beads has been attempted. The adsorption study for removal of fluoride from aqueous solution of defined concentrations has been carried out in batch mode followed by its estimation using ion-chromatography. Synthesized Zr nanoparticles are subjected to various analyses e.g. SEM, TEM, SAED EDAX and FTIR, revealing zirconium an integral component. The adsorption capacity of Zr entrapped calcium alginate beads for fluoride is found to be 90.90 mg/g. The Langmuir isotherm model best fits on equilibrium data since it provides higher R² value than Freundlich model similarly, pseudo-second order kinetic model could better explain adsorption kinetic in comparison to pseudo first order model by presenting better correlation coefficient. The overall study suggests that Zr nanoparticles entrapped in alginate beads could be a better candidate for removal of fluoride from aqueous solution. [ABSTRACT FROM AUTHOR]

In the present research work, batch adsorption study was carried out to optimize the fluoride removal capacity of guar gum hydrogel beads from aqueous solution. The adsorption capacity was found to be 71.2 mg/g. The FTIR spectrum revealed the presence of functional groups that might be involved in fluoride adsorption. Adsorption of fluoride onto bio-sorbent was investigated as a function of pH, adsorbent dosage and time. The experimental equilibrium sorption data well fitted to the Langmuir mo del and the sorption kinetics for the bio-sorbent was found to follow second order rate expression. The negative values of ΔG° suggest that the sorption of fluoride onto the bio-sorbent was spontaneous and exothermic due to the negative value of ΔH°. The negative ΔS° value for the guar gum was found to be decreasing in randomness at the solid-liquid intersection. [ABSTRACT FROM AUTHOR]

In this study we investigated the role of arsenic-resistant bacteriaArthrobactersp. biomass for removal of arsenite as well as arsenate from aqueous solution. The biomass sorption characteristics were studied as a function of biomass dose, contact time and pH. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm. The Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The biosorption capacity of the biomass for As+3and As+5was found to be 74.91 mg/g (pH 7.0) and 81.63 mg/g (pH 3.0), respectively using 1 g/L biomass with a contact time of 30 min at 28°C. The mean sorption energy values calculated from the D-R model indicated that the biosorption of As+3and As+5ontoArthrobactersp. biomass took place by chemical ion-exchange. The thermodynamic parameters showed that the biosorption of As+3and As+5ions ontoArthrobactersp. biomass was feasible, spontaneous and exothermic in nature. Kinetic evaluation of experimental data showed that biosorption of As+3and As+5followed pseudo-second-order kinetics. Fourier transform infrared spectroscopy (FT-IR) analysis indicated the involvement of possible functional groups (‒OH, ‒C\dbond O and ‒NH) in the As+3and As+5biosorption process. Bacterial cell biomass can be used as a biosorbent for removal of arsenic from arsenic-contaminated water. [ABSTRACT FROM PUBLISHER]

Biomass obtained from arsenic resistant gram positive bacteria Rhodococcus sp. WB-12 was studied for the removal of arsenite from aqueous solution. The biomass sorption characteristic was investigated as a function of biomass doses, contact time, and pH. The Langmiur Freundlich, and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm. The biosorption capacity of the biomass for As(III) was found to be 77.3 mg/g (pH 7.0) using 1 g/L biomass with the contact time of 30 min at 30°C. Kinetic evaluation of experimental data showed biosorption of As (III) followed pseudo-second-order kinetics. The Fourier transform infrared spectroscopy (FT-IR) analysis indicated the involvement of possible functional groups (-OH, -C=O, -NH) in the arsenite biosorption process. Thus, biomass derived from Rhodococcus sp. WB-12 cells has potential for use as biosorbent for the removal of arsenic from contaminated water. [ABSTRACT FROM AUTHOR]

This current investigation explored the thermal conversion process of castor wood into biochar, which was subsequently harnessed for removing naproxen from pharmaceutical industrial effluent via adsorption. Surface composition analyses conducted through scanning electron microscopy–energy dispersive X‐ray, laser‐induced breakdown spectroscopy, and Fourier‐transform infrared studies unveiled the presence of nano MgO particles within the adsorbent material. Employing optimization techniques such as response surface methodology facilitated a refined approach to batch study. The optimized conditions for batch naproxen sodium (NPX) adsorption on nano‐MgO‐modified biochar were identified as pH 4, 1.5 g/L adsorbent dosage, and a 120‐min contact time maintaining a constant NPX concentration of 10 mg/L. The adsorption capacity was calculated to be 123.34 mg/g for a nano‐magnesium oxide‐modified castor wood biochar (modified biochar) and 99.874 mg/g for pristine castor wood biochar (pristine biochar). Fenton's reagents comprising 15 mM of FeSO4 (7H2O) and 25 mM of H2O2 have been scrutinized under conditions of pH 3.0, a reaction time of 30 min, a temperature of 30°C, and stirring at 120 rpm, followed by batch adsorption treatment. The COD, NH3–N, NO3−, PO43−, and NPX removal percentages was found to be 90%, 87%, 79%, 80%, and 90%, respectively. Thus nano MgO‐modified biochar holds promise of treatment of pharmaceutical effluent. [ABSTRACT FROM AUTHOR]