Siloxane removal for biogas purification by low cost mineral adsorbent

The potential use of raw and expanded perlite as low-cost adsorbents for biogas purification has been investigated. thermal expansion causes a reduction in the density silanol groups from 2515.43 to 653.75 OH/nm2; contrast, specific surface area increased two-fold due expansion. To determine equilibrium adsorption capacity kinetics batch experiments were conducted. capacities are following order: activated carbon (6.8 mg/g) > silica gel (6.6 (5.8 (5.6 when compared at same experimental conditions. data showed that can be used reduce octamethylcyclotetrasiloxane concentration below 28 mg/m3, recommended by leading manufacturers. onto followed Linear-Driving Force model suggesting mass transfer is rate-controlling step. In addition its low cost, advantage requiring lower desorption temperature (200 °C) regeneration comparison reported values (>400 fast (20 min), which could contribute cleaner production biogas.