Development of eco-friendly, self-cleaning, antibacterial membrane for the elimination of chromium (VI) from tannery wastewater

Abstract

Hydrophobic polyvinylidene fluoride membrane was reformed to the hydrophilic membrane by incorporating synthesized titanium dioxide nanoparticles using Cajanus cajan seed extract. Spectroscopic and microscopic techniques characterized the composite membrane. The X-ray diffraction confirms the anatase phase of titanium dioxide nanoparticles of crystalline size 15.89 nm. The effect of titanium dioxide concentration on the thermodynamical and rheological properties on the polyvinylidene fluoride casting solution was investigated by the triangle phase diagram and viscosity measurement. It was concluded that titanium dioxide introduction caused thermodynamic enhancement, but the impact of rheological hinderance was higher at high concentrations. The polyvinylidene fluoride/titanium dioxide membranes were used as a bi-functional membrane to evaluate the rejection of chromium (VI) from wastewater; then, they were applied as sunlight-active catalyst membrane to reduce the concentrated chromium (VI) to chromium (III) by reduction. It was concluded that at 0.02 wt% of titanium dioxide, the maximum rejection of 85.59% and a% reduction of 92% was achieved with enhanced flux.

Sustainable and scalable development of PVDF-OH Ag/TiOx nanocomposites for simultaneous oil/water separation and pollutant degradation

“…In order to simultaneously exploit the Ag/TiO x PVDF-OH nanocomposites' capacity to separate and purify water from oily polluted sources, it was first mandatory to control the number of NPs anchored over the membrane's surface. As extensively reported, Ag and Ti can separately provide PVDF membranes with very appealing properties, such as superficial charge change 42 and antibacterial 43,44 or self-cleaning properties. 45 When found in a single NP, these properties are beneficial for the membrane's capacity to recover pure water from oily polluted sources.…”

Biopolymer‐Based Nanocomposites for Removal of Cr(VI) from Aqueous Systems: A Review

“…At the same time, costly RO membranes for reverse osmosis, certainly limit their usage in chromium removal from the environment. Current research revolves around formation of new efficient and effective RO membranes made of nano‐materials, eco‐friendly and self‐cleaning membranes, [ 21 ] and better systems for treating byproducts.…”

“…At the same time, costly RO membranes for reverse osmosis, certainly limit their usage in chromium removal from the environment. Current research revolves around formation of new efficient and effective RO membranes made of nano-materials, eco-friendly and self-cleaning membranes, [21] and better systems for treating byproducts. Apart from conventional filtration membranes, new nanofiltration membranes are under extensive research for use in Cr(VI) removal as they exhibit high Cr(VI) removal efficiency.…”

Overview on the Antimicrobial Activity and Biocompatibility of Sputtered Carbon-Based Coatings

“…Depending on the type and concentration of the third element added [17], the hydrophobicity and electrical properties are the DLC properties that experience the greatest changes [24,35]. In biological terms, the metals that are more interesting regarding their antimicrobial features, including antiviral features, are Ag [49,50,[56][57][58][59], Au [60][61][62][63][64][65][66], and Cr [67][68][69]. Different types of metallic and non-metallic elements can be integrated into the DLC matrix to improve the tribological characteristics due to the lack of reactivity of this coating.…”