Elemental Mercury Removal from Natural Gas by Cupper Sulfide Supported Alumina as a Sorbent

Feed streams of natural gas refineries and petrochemical industries contain mercury traces, threatening the environment and human health. Moreover, brazed aluminum heat exchangers are susceptible to being attacked by this component. The current research discusses the mercury removal capacities of alumina-based sorbents containing copper sulfide as an active metal. Cat-A and MRU-4 are synthesized and characterized using XRD, BET, TEM, XRF, and LECO methods. The experiments were carried out by loading the sorbents in a fixed-bed reactor, and they were sulfided by using a nitrogen gas stream containing 8 mol% of H2S at the temperature of 285oC. Then, their mercury removal capacities are measured at the temperature of 60 oC, pressure of 1 atm, and gas flow rate of 220 cm3/min versus time. Results showed that Cat-A and MRU-4 sorbents reached their static adsorption capacities of 12.1 and 19.3 wt%, respectively. Moreover, mercury adsorption variations of sorbents against time indicate that MRU-4 had faster dynamic adsorption than Cat-A sorbent. Ultimately, the characterization results also confirmed that the structures of MRU-4 and Cat-A adsorbents were mesoporous and microporous, respectively.