Synthesis and Characterisation of Zinc Layered Hydroxide Intercalated with 2-Methyl-4- Chlorophenoxyacetic Acid and its Controlled Release Application

Abstract

2-methyl-4-chlorophenoxyacetic acid (MCPA) is herbicide in group of phenoxyherbicides. It has been widely used in agriculture industry to control the weeds population especially thistle and dock. The toxicity of MCPA may impact the environment and harmful for living organisms especially human and aquatic life. This research aimed to intercalate MCPA herbicide with zinc layered hydroxide (ZLH) to form a composites (ZMCPA) and its controlled release properties. In this study, ZMCPA was prepared as an advanced delivery system by ion exchange method and further by hydrothermal treatment. The intercalations of zinc oxide were done with various MCPA concentration of 0.1 M, 0.3 M, 0.5 M, 0.7 M and 0.9 M. Intercalation performances were detected using powder X- ray diffraction (PXRD) and supported by Fourier Transform infrared spectroscopy (FTIR). The study for porosity of the composite was performed by BET analyzer. Among all of these concentrations, 0.5M represented the successful intercalation due to the presence of four sharp and intense harmonic peaks at 2θ with basal spacing of 24.6 Å, 12 Å, 8 Å and 6 Å, respectively. Herbicides release study was conducted in three salt solution, sodium chloride, sodium carbonate and sodium phosphate. Sustain release of MCPA was faster in sodium phosphate solution by 85%. This controlled release study was determined by UV-Vis spectrometry.