Tag Archive for: Bituminous

Reduced graphene oxide (r-GO) is a derivative of graphene which has good electrical conductivity, so it can be used as a composite in the industrial sector. The manufacture of graphene oxide (GO) as the basic material for r-GO is carried out using green chemistry one of them is using the sonication technique and citric acid reductant. This research aims to isolated r-GO from East Kalimantan Bituminous coal which has 70,24% carbon content. The citric acid was varied on 10%, 30%, and 50% and the applies sonication duration was 10, 30, and 50 minutes. In order to obtain the optimal r-GO which was evaluated according to the lowest yield. The optimal condition took place at 10% citric acid under 50 minutes sonication. The r-GO was characterized using FTIR and it showed that the peaks of C-OH, C=C, and C-O-C exhibiting the high %T. The morphology of selected r-GO was closed to the references based on SEM analysis. There was an increase about 50,20% of carbon content in r-GO (84,412%) compared to the GO (56,199%). On the other hand, the percentage of oxygen decreased by 64,27% for GO (23,785%) to selected r-GO (8,498%). There was a change of C:O ratio, from 2,409 (GO) to 9,935 (r-GO). Its density and pH for r-GO were 1,4 g/cm³ and 2.