Management of tannery waste effluents towards the reclamation of clean water using an integrated membrane system: A state-of-the-art review.

Tanning and other leather processing methods utilize a large amount of freshwater, dyes, chemicals, and salts and produce toxic waste, raising questions regarding their environmental sensitivity and eco-friendly nature. Total suspended solids, total dissolved solids, chemical oxygen demand, and ions such as chromium, sulfate, and chloride turn tannery wastewater exceedingly toxic for any living species. Therefore, it is imperative to treat tannery effluent, and existing plants must be examined and upgraded to keep up with recent technological developments.

Waste to catalyst: Role of agricultural waste in water and wastewater treatment.

Presently, owing to the rapid development of industrialization and urbanization activities, a huge quantity of wastewater is generated that contain toxic chemical and heavy metals, imposing higher environmental jeopardies and affecting the life of living well-being and the economy of the counties, if not treated appropriately. Subsequently, the advancement in sustainable cost-effective wastewater treatment technology has attracted more attention from policymakers, legislators, and scientific communities. Therefore, the current review intends to highlight the recent development and applications of biochars and/or green nanoparticles (NPs) produced from agricultural waste via green routes in removing the refractory pollutants from water and wastewater.

Effect of pandemic based online education on teaching and learning system.

Coronavirus outbreak mediated pandemic impacted most of the sectors globally. This includes the academic world that consists of millions of enrolled learners and active teachers who previously had regular classes in their institutions, and due to the pandemic, got stuck at the home. To continue the education process, the online class was introduced in most of the countries, including India.

Impact of social lockdown due to COVID-19 on environmental and health risk indices in India.

Coronavirus disease (COVID-19) spread across the globe through the human transmission. The World Health Organization suggested social distancing to curb the community spread. After national social lockdown started in India, air quality improved drastically.

An upgraded electro-Fenton treatment of wastewater using nanoclay-embedded graphene composite prepared via exfoliation of pencil rods by submerged liquid plasma.

In this work, two types of electrochemical electrodes were synthesized using two types (i.e., 4 black (4B) and hard black (HB)) of pencil rods during submerged liquid plasma (SLP) process.

Single-step removal of Hexavalent chromium and phenol using meso zerovalent iron.

Novel meso-zero valent iron (mZVI) was investigated for treating complex wastewater containing toxic heavy metal Cr and organic compound phenol. This study is first of its kind illustrating coupled removal in single-step with HO playing a major role as an oxidant and reductant. The mechanism involved was electron transfer from Fe to Cr resulting in Fe which in turn was consumed for phenol oxidation returning as Fe into the system for further Cr reduction.

Synthesis, characterization and performance of high energy ball milled meso-scale zero valent iron in Fenton reaction.

Understanding contaminant degradation by different sized zero valent iron (ZVI) particles is one important aspect in addressing the long-term stability of these particles in field studies. In this study, meso zero valent iron (mZVI) particles were synthesised in a milling time of 10 h using ball milling technique. The efficacy of mZVI particles for removal of phenol was quantitatively evaluated in comparison with coarse zero valent iron (cZVI) and nano zero valent iron (nZVI) particles.

Performance enhancement of zero valent iron based systems using depassivators: Optimization and kinetic mechanisms.

The long-term ability of Zero-Valent Iron (ZVI) in contaminant removal relies on the effectiveness of iron to serve as electron donor, which makes it a versatile remediation material. However, the formation of oxide and hydroxide layers results in passive layer on ZVI surface during contaminant removal hinders its reactivity. The focus of this research was to evaluate the performance of corrosive agents such as acetic acid (HAc), aluminium sulphate (Alum) and potassium chloride (KCl) as depassivators to overcome passivation for sustainability and longevity.