Electrochemical treatment of simulated sugar industrial effluent: Optimization and modeling using a response surface methodology

The removal of organic compounds from a simulated sugar industrial effluent was investigated through the electrochemical oxidation technique. Effect of various experimental parameters such as current density, concentration of electrolyte and flow rate in a batch electrochemical reactor was studied on the percentage of COD removal and power consumption. The electrochemical reactor performance was analyzed based on with and without recirculation of the effluent having constant inter-electrodes distance. It was found out that the percentage removal of COD increased with the increase of electrolyte concentration and current density. The maximum percentage removal of COD was achieved at 80.74% at a current density of 5 A/dm2 and 5 g/L of electrolyte concentration in the batch electrochemical reactor. The recirculation electrochemical reactor system parameters like current density, concentration of COD and flow rate were optimized using response surface methodology, while COD removal percents were maximized and power consumption minimized. It has been observed from the present analysis that the predicted values are in good agreement with the experimental data with a correlation coefficient of 0.9888

<i>Amaranthus spinosus</i> Leaf Extract Mediated FeO Nanoparticles: Physicochemical Traits, Photocatalytic and Antioxidant Activity

Iron oxide nanoparticles were synthesized using Amaranthus spinosus leaf aqueous extracts reducing from ferric chloride. A. spinosus leaf extract is a rich source of amaranthine and phenolic compounds with high antioxidant and these molecules were used as reducing agents. The operating parameters of nanoparticles synthesis were optimized. Physicochemical, optical, and magnetic properties of synthesized nanoparticles were characterized using analytical techniques. Results confirmed that A. spinosus leaf extract mediated iron oxide nanoparticles are spherical shape with rhombohedral phase structure, smaller size, and large surface with less aggregation. The photocatalytic and antioxidant activities of leaf extract as well as sodium borohydride mediated iron oxide nanoparticles were studied. The percentage decolorization of methyl orange and methylene blue was 75% and 69%, respectively, for extract mediated iron oxide nanoparticles under sunlight. The antioxidant efficiency was also observed to be 93% against 2,2-diphenyl-1-picrylhydrazyl. The extract mediated iron oxide nanoparticles showed better photocatalytic and antioxidant capacity than sodium borohydride mediated nanoparticles

Strategy for Multifunctional Hollow Shelled Triple Oxide Mn–Cu–Al Nanocomposite Synthesis via Microwave-Assisted Technique

A facile route for assembling hollow shelled triple Mn–Cu–Al oxide nanomaterials (HMCA) using the microwave-assisted reduction technique is demonstrated, and the energy and environmental applications such as supercapacitor and photocatalyst are investigated. During the reaction time, MnO₂, CuO, and Al₂O₃ formed a shell layer over the core SiO₂ and assembled as a hollow geometrical nanostructure with a uniform size densely populated hairy outer appearance. We have shown that the resultant HMCA exhibited the synergistic effects of a nanocomposite and thereby revealed a distinctive collection of physical and chemical properties such as improved electrochemical capacitive performance capacities, enhanced photocatalytic activities, and increased adsorption. These features collectively confirmed the potential of HMCA as an attractive material for resourceful applications in environmental and energy storage issues

Effects of operating parameters on permeation flux for desalination of sodium chloride solution using air gap membrane distillation

Desalination of sodium chloride solution has been experimentally investigated by air gap membrane distillation. The effects of process parameters, feed temperature, feed flow rate, feed salts concentration and air gap thickness on the permeation flux have been studied. The flux increases with increasing feed temperature and flow rate. The flux decreases with increasing salt concentration, air gap thickness. Using commercially available PTFE membranes of 0.01382 m2 area, the maximum permeate flux was 9.4 L/m2h at 80°C with flow rate of 250 ml/min. The salt rejection was observed nearly 99.9% in the all experimental conditions. The AGMD is an ideal process for application of desalination and also alternative process compare to conventional distillation and reverse osmosis

Review on cultivation and thermochemical conversion of microalgae to fuels and chemicals: Process evaluation and knowledge gaps

Over the last decades, microalgae have gained a commendable role in the rising field of biofuel production as they do not compete with food supply, reduce greenhouse gases emission, and mitigate CO2. Specifically, thermochemical processing of microalgae yields products, which can be used both for energy and other industrial purposes, depending on the algal strain, processing method and operative conditions. Algae are converted into various high-value products, including nutraceuticals, colourants, food supplements, char, bio-crude, electricity, heat, transportation fuel, and bio-oil. Therefore, microalgae are believed to be a strategic resource for the upcoming years and their utilization is meaningful for many industrial sectors. In this framework, this review addresses the various thermochemical processing of microalgae to various biofuels and their industrial significance. The obstacles in various thermochemical conversion methods have been critically flagged, in order to enable researchers to choose the optimal method for fuel production. Furthermore, light is shed on cultivation systems to generate rapidly microalgal biomass for thermochemical processing. Eventually, all recent literature advancements concerning microalgae cultivation and thermochemical processing are critically surveyed, and summariz