Eficiência da sílica bimodal como adsorvente do dióxido de carbono para o tratamento do gás natural

Abstract

The production of Natural Gas (NG) in Brazil has shown a significant increase in the years, mainly with the operations of the pre-salt platforms. However, pre-salt NG presents a technical and economic challenge due to the presence of contaminants in the gas, mainly CO2, since it has a higher concentration, with reserves that provide more than 70%, requiring different technological solutions. Thus, the development of technologies and materials that capture CO2 and that present the best cost-benefit ratio is of great importance in the Oil industry. New technologies using materials that capture CO2 have been efficient in relation to conventional processes, lower costs and ease of preparation, as an adsorbent on silica bases. Therefore, in this work, a hybrid adsorbent of mesomacroporous silica was synthesized for CO2 adsorption of NG, being promising for use in natural gas treatment systems, as it has specific textural properties for the capture and storage of this gas. The adsorbent was established from silica, by the hydrothermal method, and improved by the techniques of X-ray diffraction, lifting electron microscopy and specific surface area by the BET method. The adsorption capacity tests were performed for CO2, methane (CH4) and their mixtures, in a magnetic suspension microbalance, characterized that the adsorbent was selective for CO2 and obtaining a good adsorption capacity (9.10 mmol.g- 1). The experimental values obtained were compared and adjusted to the Langmuir and Freundlich models. Thus, the hybrid silica adsorbent developed in the research proved to be excellent for CO2 adsorption and not for CH4, being a promising material for the treatment of NG.