Characteristic study of graphene oxide (GO) coated sand proppant / Nurul Ain Norazmi

Hydraulic fracturing is a well stimulation method performed on reservoirs with low permeability to improve the flow of hydrocarbon into wellbore. Certain chemicals are injected into the well under very high pressure; propping agent, such as sand is added to the fracturing fluid to keep the fracture open. In order to study the performance of coated sand used in application of hydraulic fracturing, local sands are improved by surface modification using Graphene Oxide (GO) as the coating agent. The interaction of GO and sand are confirmed through Fourier-Transform Infrared (FT-IR) and Scanning Electronic Microscopy (SEM). The image of SEM showed that the coating of GO had modified the uneven/rough surface of uncoated sand. In order to study the performance of GO sand proppant, a series of laboratory tests were performed according to the recommended practice International Standard Organization (ISO13503-2) and American Petroleum Institute (API 19C). The roundness and sphericity, acid solubility, crush resistance and grain size were measured for all samples. The results of sphericity and roundness showed that only Sample 4 satisfied the standard requirement. Acid solubility of Sample 4, 5, 6, 7, and 8 have met the API requirement. The turbidity values for all samples are varied from 21-80 FTU, agreed with the ISO recommended. GO coated sand have a potential characteristic as a proppant. GO can be used to smooth the surface of uncoated sand, improve the strength, decreased the solubility acid of sand and make it more desirable as proppant.