Beneficial role of ZnO photocatalyst supported with porous activated carbon for the mineralization of alizarin cyanin green dye in aqueous solution

The present investigation depicts the development of a simple and low cost method for the removal of color from textile dyeing and printing wastewater using ZnO as photocatalyst supported with porous activated carbon (AC). Photocatalytic degradation studies were carried out for water soluble toxic alizarin cyanin green (ACG) dye in aqueous suspension along with activated carbon (AC) as co-adsorbent. Different parameters like concentration of ACG dye, irradiation time, catalyst concentration and pH have also been studied. The pseudo first order kinetic equation was found to be applicable in the present dye-catalyst systems. It was observed that photocatalytic degradation by ZnO along with AC was a more effective and faster mode of removing ACG from aqueous solutions than the ZnO alone

Synthesis and corrosion protection properties of poly(o-phenylenediamine) nanofibers

AbstractThe present study shows a novel method for the synthesis of uniformly-shaped poly(othophenylediamine) (PoPD) nanofibers by chemical oxidative polymerization method for application towards smart corrosion resistance coatings. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) studies confirm morphology of PoPD with three dimensional (3D) networked dendritic superstructures having average diameter of 50–70nm and several hundred meters of length. UV–vis and FTIR spectral results shows the formation of PoPD nanofibers containing phenazine ring ladder-structure with benzenoid and quinoid imine units. Thermogravimetric analyses (TGA) of PoPD nanofibers possess good thermal stability. The anti-corrosion behavior of PoPD nanofibers on 316L SS was investigated in 3.5% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements. The PoPD coated 316L SS exhibits higher corrosion potential when compared to uncoated specimen. EIS studies, clearly ascertain that PoPD nanofiber coatings exhibits excellent potential barrier to protect the 316L SS against corrosion in 3.5% NaCl

Synchronous role of coupled adsorption and photocatalytic degradation on CAC–TiO2 composite generating excellent mineralization of alizarin cyanine green dye in aqueous solution

The synchronous role of coupled adsorption and photocatalytic degradation of alizarin cyanine green dye (ACG) in aqueous solution on porous Commercial Activated Carbon (CAC)–titanium dioxide (TiO2) mixture have been studied under UV irradiation. The CAC–TiO2 composite was prepared by simple chemical route and the as prepared composite was characterized using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis. The photodegradation rate constant (k) for ACG dye on CAC–TiO2 is (0.0666 min−1), which is very much higher than that of pure TiO2 0.00368 min−1. The photodegradation efficiency of the CAC–TiO2 composite was eighteen order magnitudes higher than that of pure TiO2 for ACG dye degradation. The total mineralization of ACG, through the combination of adsorption and degradation was achieved in a reasonable time, and can therefore be suggested as an efficient, cost-effective and environment friendly water treatment methodology