SEM and XRD for removal of heavy metals from industrial wastewater and characterization of chicken eggshell.

Heavy metal toxicity due to industrial wastewater has been a threat to the environment for the past many decades, especially in developing countries. Electroplating Industry wastewater containing heavy metals can become a serious environmental pollutant if not treated appropriately. Present study investigated the removal of nickel and chromium ions from electroplating wastewater using calcined hen eggshells because of it high removal capability, little cost and easy approachability. Characterization of the adsorbent such as proximate analysis, surface charge, X-ray diffraction, and surface area was done prior to adsorption process. Batch adsorption experiment was performed to study the effect of different parameters such as adsorbent dose, contact time, temperature, and pH for adsorbent. Removal percentage of both heavy metals was checked by using calcined eggshell as adsorbent. Comparison was made between nickel and chromium to identify the most effective removal efficacy. It was concluded that utilization of natural waste was found suitable, easier, cost operative and environmental approachable for removal of heavy metals from industrial wastewater. RESEARCH HIGHLIGHTS: To use ecofriendly approach for the treatment of industrial wastewater. To used calcined eggshell as adsorbents for removing metal concentration from industrial wastewater. To find the metal removal potential of calcined eggshell under various environmental conditions like dosage, contact time, temperature, and pH. To checking the efficacy of calcined eggshell.

Reduction of reactive red 241 by oxygen insensitive azoreductase purified from a novel strain Staphylococcus KU898286.

An oxygen insensitive azoreductase was purified from a novel bacterial strain (Staphylococcus sp. KU898286) that was isolated from an abandoned site of the textile waste discharge unit. The isolated enzyme had efficiently cleaved the azo-bonds through reductive transformation under aerobic conditions. Initial phenotypic characterization and final construction of phylogenetic tree on the basis of 16s rDNA demonstrated 99% resemblance of the isolate to Staphylococcus aureus. The purified azoreductase was found to have a broad spectrum activity that reduced RR241 at a concentration of 50mg/L with pH between 6-8 and 30°C temperature). Besides, the reactive red 241 (RR241) was reduced at extracellular level as well as NADH dependent intracellular level. Complete reduction/ decolourization of RR241 were achieved after 18 hrs of exposure. The final degradation product observed to be 2-nephthol was purified by High Pressure Liquid Chromatography (HPLC) and the molecular mass was computed by Gas Chromatography-Mass spectroscopy (GC-MS). The study revealed a cost effective and eco-friendly approach to degrade the toxic dyes into less toxic products by Staphylococcus sp. KU898286.