Biosafe organic diacid intercalated LDH/PVC nanocomposites versus pure LDH and organic diacid intercalated LDH: Synthesis, characterization and removal behaviour of Cd2+ from aqueous test solution

Abstract

Highly real nanostructured clay adsorbents of layered double hydroxide(LDH) intercalated with biosafe and anionic organic diacid was produced at a constant pH with the coprecipitation method. XRD results disclosed that organic anionic segment is horizontally oriented in the interlayer space, which is obvious from developed basal spacing of 0.76 to 1.36 nm. Also, a successfully LDH intercalation with examined biosafe diacid was observed using FT-IR and TGA analysis. Organo-intercalated LDH (I-LDH)/PVC nanocomposites (NCs) with different content of I-LDH loading were organized through ultrasound irradiation as a green method. The morphological behaviors and structured properties of achieved NCs were studied by characteristic analyses such as FT-IR, XRD FE-SEM and TEM. Results of thermal analysis disclosed positive influence of I-LDH on degradation temperature in compared to the neat PVC, and also residue at 800 °C enhanced from 23 to 42%. The resulting LDH samples were studied for their performance in removing Cd^2 + metal ion from aqueous test solution and the removal efficiency of these materials at proper pH, different adsorbent mass, Cd^2 + concentrations and different times were documented by atomic adsorption spectrometry. In all samples, with the developed in the adsorbent mass, the removal efficiency for Cd^2 + was improved at the 50 mg/L of metal ion concentration and constant pH of 7.0. The maximum Cd^2 + uptake was 86.17% related to the I-LDH/PVC NC 15 wt%, and also the experimental data indicated a good compliance with the Langmuir isotherm and pseudo-second-order kinetic model for different LDH samples.