Electrochemical-based approaches for the treatment of forever chemicals: Removal of perfluoroalkyl and polyfluoroalkyl substances (PFAS) from wastewater.

Electrochemical based approaches for the treatment of recalcitrant water borne pollutants are known to exhibit superior function in terms of efficiency and rate of treatment. Considering the stability of Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are designated as forever chemicals, which generating from various industrial activities. PFAS are contaminating the environment in small concentrations, yet exhibit severe environmental and health impacts. Electro-oxidation (EO) is a recent development that treats PFAS, in which different reactive species generates at anode due to oxidative reaction and reductive reactions at the cathode. Compared to water and wastewater treatment methods those being implemented, electrochemical approaches demonstrate superior function against PFAS. EO completely mineralizes (almost 100 %) non-biodegradable organic matter and eliminate some of the inorganic species, which proven as a robust and versatile technology. Electrode materials, electrolyte concentration pH and the current density applying for electrochemical processes determine the treatment efficiency. EO along with electrocoagulation (EC) treats PFAS along with other pollutants from variety of industries showed highest degradation of 7.69 mmol/g of PFAS. Integrated approach with other processes was found to exhibit improved efficiency in treating PFAS using several electrodes boron-doped diamond (BDD), zinc, titanium and lead based with efficiency the range of 64 to 97 %.

Malic acid production from biodiesel derived crude glycerol using morphologically controlled Aspergillus niger in batch fermentation.

In the present investigation, the effects of crude glycerol concentration, spore inoculum concentration, yeast extract concentration and shaking frequency on seed morphology of Aspergillus niger PJR1 on malic acid production were investigated and dispersed fungal mycelium with higher biomass (20.25 ±â€¯0.91 g/L) was obtained when A. niger PJR1 grow on crude glycerol. Dry cell weight under dispersed fermentation was 21.28% higher than usual pellet fermentation. The optimal crude glycerol, nitrogen source and nitrogen source concentration were found to be 160 g/L, yeast extract and 1.5 g/L, respectively. Batch fermentation in a shake flask culture containing 160 g/L crude glycerol resulted in the yield of malic acid 83.23 ±â€¯1.86 g/L, after 192 h at 25 °C. Results revealed that morphological control of A. niger is an efficient method for increased malic acid production when crude glycerol derived from biodiesel production is used as feedstock.

Ultrasonic assisted green synthesis of Fe and Fe/Zn bimetallic nanoparticles for invitro cytotoxicity study against HeLa cancer cell line.

Nanomaterial synthesis for the biomedical application is the latest improvement in nanotechnology. These nanomaterials can be used as therapeutic agent, drug carrier and also as activating agents. When the nanoparticles are prepared from biological sources, they show better medical competence with fewer side effects. Iron and zinc oxide nanoparticle have been found to exhibit good antimicrobial property; hence this bimetallic nanoparticle can be used for biomedical applications. Therefore the present work focused on synthesis of iron oxide and Fe/Zn bimetallic nano particle by Coriandrum sativum leaf extract as reducing agent using ultrasonic assisted method. The UV-Vis spectroscopy was used to confirm the synthesized nanoparticle. The crystallinity and shape of the particle formed was confirmed by XRD and SEM. The HeLa cell line and normal cell line were used to find the invitro cytotoxic activity of iron oxide and Fe/Zn bimetallic nanoparticle. Fe/Zn bimetallic nanoparticle and Iron oxide nanoparticle showed 61.96% and 54.95% cytotoxicity at 200 µg/ml concentration respectively against HeLa cancer cell line.

Ultrasound assisted phytosynthesis of iron oxide nanoparticle.

The present work deals with the ultrasound assisted green synthesis of iron oxide nano particle using Coriandrum sativum leaf extract as a reducing agent. The synthesized iron oxide nanoparticle was confirmed by UV spectra. The characterization was done to know more about morphology and size of the particle by SEM analysis which shows spherical particles with size ranging from 20 to 90nm. The antimicrobial activity of the leaf extract and the synthesized nanoparticles was studied against the pathogens Micrococcus luteus, Staphylococcus aureus and Aspergillus niger. The ultrasound assisted iron oxide nanoparticle shows higher scavenging activity and antimicrobial activity compared with iron oxide nanoparticle synthesized by magnetic stirrer and Coriandrum sativum leaf extract.

Electrochemical treatment of tannery effluent using a battery integrated DC-DC converter and solar PV power supply--an approach towards environment and energy management.

Electrochemical oxidation of tannery effluent was carried out in batch, batch recirculation and continuous reactor configurations under different conditions using a battery-integrated DC-DC converter and solar PV power supply. The effect of current density, electrolysis time and fluid flow rate on chemical oxygen demand (COD) removal and energy consumption has been evaluated. The results of batch reactor show that a COD reduction of 80.85% to 96.67% could be obtained. The results showed that after 7 h of operation at a current density of 2.5 A dm(-2) and flow rate of 100 L h(-1) in batch recirculation reactor, the removal of COD is 82.14% and the specific energy consumption was found to be 5.871 kWh (kg COD)(-1) for tannery effluent. In addition, the performance of single pass flow reactors (single and multiple reactors) system of various configurations are analyzed.