Preliminary Study of Chitosan Coating Silica Derived from Geotermal Solid Waste

Abstract

Purpose: The purposes of this research are to study preparation of chitosan coating silica aerogel derived from solid geothermal waste as adsorbent of CO2 and CH4 separation and to study CO2 adsorption kinetics on chitosan coating silica aerogel by Pseudo First Order and Second Order methods. Methodology was conducted consisting of several steps. First, geothermal silica was leached with H2SO4 20% 1: 5 w/v. Then, chitosan was added into silica with ratio of 1.3: 10, 1.5: 10, 1.9: 10, 2.2: 10, and 2.4: 10 w/v. Isopropyl alcohol was added to silica sol to form hydrogel and remained in gelation. The addition of n-hexane was carried out to occur the solvent exchange process. The gel was dried by ambient pressure drying method. CO2 in biogas was removed of using 20 g of adsorbent chitosan coating silica aerogel. The experimental adsorption kinetics analyzed by both pseudo first and second order kinetics model. Results showed that impurities in geothermal silica required to be purified and it can be synthesized into silica aerogel. The remaining geothermal can act as adsorbents to silica aerogel coated with chitosan by using packed column. The data obtained was kinetics data from the pseudo first and second order method. The silica from solid geothermal waste has the potential as CO2 adsorbent. Applications/ Originality/ Value: It was confirmed that silica from solid geothermal waste can be used as CO2 adsorbent. Therefore, the improvement of innovation in the future of this research is to prepare chitosan coating silica aerogel as CO2 adsorbent.