Nanocellulose Based Composites for Chromium Decontamination in Aqueous System

Abstract

This thesis work deals with nanocellulose based composite (Polyaniline nanocellulose composites and Carboxymethyl Nanocellulose stabilized nZVI) for removal and citrate capped AgNPs for detection of chromium in water samples. The existence of chromium in environment and their permissible limits set by different environmental monitoring agencies. Also, the available methods for the removal and detection have been discussed. Role of nanotechnology in removal and detection of chromium have been studied extensively. Various fabrication methods for nanocellulose based composites (PANI-NC and CMNc-stabilized nZVI) used for the chromium removal and citrate capped AgNPs used for the chromium detection are given. The characterization tools used for the validation of optical, morphological and functional properties of the above synthesized nanocomposites have been provided in the chapter. For removal of chromium two nanocellulose based composites have been synthesized and a hand held device has been developed for the detection of chromium. The various characterizing tools used were UV-vis spectroscopy, DLS, SEM, and TEM. XRD, FTIR, TGA and AAS. The batch experiment has also been conducted. The next section deals with the optimization studies to validate the effect of different conditions (pH, temperature, contact time, adsorbent dose and concentration of chromium) for both the nanomaterials. Procedure for the device fabrication has been introduced in the end. In case of detection a portable nanomaterial based hand held device has been fabricated Feasibility of the device was then checked in different water samples. Interference studies have also been conducted for different heavy metals. The device was highly efficient with LOD of 26 ppb and reproducible. All this proves that Nanocellulose based composites are highly efficient for chromium removal from water samples. newline newline