Kaliolla, Kemelkhan2024-06-272024-06-272024-04-18Kaliolla, K. (2024). Characterization and Performance Assessment of SiO2-KCl-Xanthan Nanocomposite as a Novel nano-Asphaltene Precipitation Inhibitor under Laboratory Conditions. Nazarbayev University School of Mining and Geoscienceshttp://nur.nu.edu.kz/handle/123456789/8046In this experimental research work, efficiency of SiO2-KCl-Xanthan nanocomposite (NC) as a nano-inhibitor for adsorption and removal of asphaltene from a synthetic crude oil medium was investigated. The NC has been used as an EOR and smart drilling fluid agent with impressive results. This was the motivation behind this research work. The first phase of the research involved extraction of asphaltene from a West Kazakhstani heavy crude oil and characterization of both asphaltene and the NC. Different state of the art analytical techniques including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller or BET, X-ray diffraction (XRD), and thermogravimetric or TGA were used for NC. This was to ensure authenticity and functionality of the NC. The NC has a spherical structure with particle sizes ranging from 30 to 300 nm determined using SEM analysis. The crystallite size was calculated 41 nm using the XRD data. The surface area of the NC was determined 31.95 m2/g using the BET method. TGA analysis showed that the NC did not experience any significant mass loss for a typical reservoir temperature (80°C) and it is thermally stable for oilfield applications. Based on the FTIR spectra, presence of organic functional groups of phytochemicals on the NC was identified indicting successful synthesis of the NC. The last stage was to assess the efficiency of the nano-inhibitor by determining the Asphaltene Onset Point (AOP) using UV-vis spectroscopy technique and asphaltene adsorption kinetics isotherm modeling using the supernatant obtained from TGA analysis. TGA analysis confirmed that oxidation of virgin asphaltene started at around 400 to 450℃. While, oxidation of 5,000 ppm sample with NC started at around 280℃. The NC has catalyzed oxidation of the asphaltene. Adsorption kinetics isotherm modeling was done using the Langmuir (R2 = 0.98) and Freundlich (R2 = 0.82) isotherm models. The experimental data matched well both models, which suggests monolayer and multilayer adsorption behavior for adsorption of asphaltene onto the surface of the NC. A maximum adsorption capacity of 1.33 mg/m2 was obtained for the NC. The novel nano-inhibitor shifted the AOP by 5% and the optimum concentration of NC was determined 0.3 wt%. Overall, the NC showed promising inhibitory performance under laboratory conditions.enAttribution 3.0 United StatesType of access: EmbargoAsphaltene precipitation inhibitionnano-inhibitors SiO2-KCl-Xanthan nanocompositeadsorptionAOPMaster's thesis