Synthesis of CNS, ZnO/CNS and ZnCr2O4/CNS composites from patchouli biomass by using microwave for remediation of pesticide contaminated surface water in paddy field

Patchouli biomass is a potential precursor for CNS synthesis. In this research, the patchouli was pyrolyzed using the microwave. The purpose of this research is to study the effect of microwave energy and activator toward physicochemistry of CNS and composite (ZnO/CNS) and application of ZnCr2O4/CNS for the pesticide polluted surface water remediation in paddy field. In the process, the biomass was pyrolyzed at four and 8W with and without the ZnCl2 activator. The products were blended and evaporated to obtain CNS and ZnO/CNS. The products were characterized using FTIR spectrometry, XRD, and dispersion test. The composites were used to synthesize ZnCr2O4/CNS at 600W in the microwave. The composites were used for buthylphenylmethyl carbamate pesticide degradation test (BPMC) for 48 h with H2O2 oxidation. The FTIR spectra indicated better carbonization for products taken using an activator at both microwave energies. The X-ray diffractograms showed the turbostratic structure of carbon obtained at 4W pyrolysis (with activator), meanwhile 8W pyrolysis (without activator). ZnO and turbostratic carbon structures were shown by the product of 8W pyrolisis with activator. The calcined composite indicated ZnCr2O4/CNS. The degradation test showed that ZnCr2O4/CNS(8W) catalyst decreased the BMPC concentration almost three times that of the composite (4W).