Removal of chlorpyrifos using carboxymethyl cellulose nanocrystal membrane: characterization and adsorption study / Norzakiatul Husna Isnolamran

The cellulose nanocrystals (CNCs) was successfully isolated from oil palm empty fruit bunch (OPEFB) using acid hydrolysis method. The CNCs obtained was functionalized into carboxymethyl cellulose nanocrystals (CMCNCs) through carboxymethylation technique using monochloroactic acid (MCA) which undergo two steps process which were alkalization followed by etherification. Based on FTIR spectra, the decreasing in the intensity of peak around 1320 cm-1 on CMCNCs spectra indicated the substitution of carboxyl group (COO) on the CNCs surface. The thermal stability of CNCs and CMCNCs powder were determined using thermogravimetric analyzer (TGA). The result shows the CMCNCs has higher thermal stability compared to CNCs as the functional group on the CNCs surface was modified. The prepared membrane than were compared by its capacity of absorption. The comparison observed that the capacity of water absorption was increased with the increasing of CNCs and CMCNCs dispersion in membrane. The adsorption study was done to identify the optimum membrane concentration to reduce the chlorpyrifos absorbance in its solvent by testing in 1 ppm concentration of chlorpyrifos. The absorbance of chlorpyrifos were determined using Ultraviolet- visible spectrometer (UV-Vis). The result of the adsorption study were show the degradation of the initial absorbance of chlorpyrifos peak at 230 nm by 1% CNCs membrane, 1%, 5%, 7%, and 9% CMCNCs membranes. This result shows the CMCNCs membrane has better removal ability compared to CNCs membrane. These finding validated this CNCs and CMCNCs membrane application was suitable for chlorpyrifos adsorption due to their promising and economically feasible technology.