Treatment effect of titanosilicate ETS-10 on heavy hydrocarbon adsorption

Abstract

Heavy hydrocarbons must be separated from natural gas for various reasons, including two-phase formation in transportation pipelines. One of the most important methods for this purpose is the adsorption method. However, there is a lack of studies on heavy hydrocarbons’ adsorption on titanosilicates as an early-developed adsorbent. In this work, titanosilicate ETS-10 was evaluated for the adsorption of heptane, as a representative of heavy hydrocarbons. To study the effect of ETS-10 treatment on its properties and consequently heavy hydrocarbon adsorption, the synthesized samples were treated by different methods such as using an organic template, changing the solvent, fluorination and ion exchanging. All samples were characterized by combined analyses and their heptane adsorption was studied by volumetric method. Results showed that ETS-10 treatment leads to an increase in the mesoporosity of ETS-10. Also, using organic directing agents and isopropanol solvents resulted in better crystallization and higher adsorption capacity for the prepared ETS-10. It was observed that in a 3-h degassing at 300 °C, the HF-ETS-10 sample had the highest heptane uptake (1.84 mmol/g) which is more than twice that of ETS-10. Further evaluation confirmed that adsorption capacity of this sample remained constant after being used for 5 cycles of adsorption-desorption. It was concluded that ETS-10 can be suggested as an attractive adsorbent for heavy hydrocarbon removal.