GREEN NANOTECHNOLOGY APPROACH FOR DYE-CONTAMINATED WASTEWATER TREATMENT: ADSORPTIVE POTENTIAL OF SILVER NANOPARTICLES DERIVED FROM ABIES PINDROW CONES

Abstract

Dye is used to color different products in many industries, such as cosmetics, pigments and textiles. Approximately one hundred thousand commercial dyes are produced by industries and annually global production of associated dyes exceeding 7× 10^-5 tons. The purpose of present study is use of silver nanoparticles derived from Abies pindrow cone (APC) as an adsorbent for the removal of methylene blue dye from aqueous solution. The prepared Abies pindrow cone Ag-NPs (APC-Ag-NPs) were characterized using FTIR, SEM and EDX for surface functional groups and morphology and elemental analysis. The zeta potential and average size of APC-Ag-NPs) were verified via ELS and DLS. Furthermore, statistical analysis was incorporated to validate adsorption efficiency. Some factors being analyzed in the study include adsorbent dosage, initial dye concentration, variable particle size and temperature. It was found that increasing the adsorbent dose led to reduced dye removal due to underutilization of available sites. Particle sizes below 3.0 also increased dye removal because the smaller size allowed a large surface area and more available attachment sites. The removal efficiencies increased with the increase in initial dye concentration, due to the concentration gradient. Increasing temperature led to reduced removal of dye, presumably because adsorbate-adsorbent interactions are relatively poorer and dyes become soluble. Statistical analysis was undertaken to test the importance of the adsorption trends. The mechanism of adsorption was also examined using Langmuir and Freundlich isotherm models to allow gain of further information regarding the process of adsorption. Our findings reveal that, the APC-Ag-NPs have improved efficacy of removing dye