Chemical Engineering, Universitas Sumatera Utara
Corncob is one of the industrial waste has cellulose content of 39.1 wt%, which makes it has high potential to be a raw material in the production of cellulose nanocrystal. Corncob was delignificated with 3.5 wt% HNO3 and NaNO2 10 mg, precipitated process with 17.5 wt% NaOH, and bleached with 10 wt% H2O2. Cellulose nanocrystal was obtained by hydrolysis using 45 wt% H2SO4. Corncob and cellulose nanocrystal was characterized by Fourier Transform Infra Red (FTIR) and showed that the absorption peak indicated the presence of cellulose clusters was obtained from corncob and cellulose nanocrystal has many similarities and there was no new bond formation. Cellulose nanocrystal particle size was observed by Transmission Electron Microscopy (TEM) and the result showed the size of cellulose nanocrystal was 9-29 nm. Crystallinity index of cellulose nanocrystal from corncob determined by X-Ray Diffraction (XRD) was 70%. This showed the atomic structure of cellulose nanocrystal quite regular so obtained a high crystallinity index.