SnO _x -Impregnated Clinoptilolite for Efficient Mercury Removal from Liquid Hydrocarbon

The present study investigates SnO _x-impregnated clinoptilolite, which is zeolite belonging to the heulandite family, for developing efficient adsorbent for mercury removal from liquid hydrocarbon. Adsorption experiments were carried out in batch method, and the effects of adsorbent dosage and contact time on the adsorption properties of mercury were investigated. We demonstrated that the SnO _x-impregnated clinoptilolite removed the mercury from liquid hydrocarbon with high efficiency, where the maximum capacity was 0.93 ng/g, higher compared with the natural clinoptilolite (0.43 ng/g). Structure and morphology analysis also showed that SnO _x was coated on the surface of clinoptilolite, resulting in rougher surface and smaller pore size and volume than those of natural clinoptilolite. Speciation of mercury indicated that the most removed species was organomercury (67.3%), and its removal efficiency increased with the adsorbent dosage. The isotherm analysis revealed that adsorption mechanism was governed by pseudo-second-order kinetics, indicating that the adsorption was a chemical adsorption process due to electrostatic attractions. This finding suggested that clinoptilolite/SnO _x was promising adsorbents for organomercury removal from liquid hydrocarbon.