Process gas desulfurization at high temperature with mesoporous Cu-MCM-41

Researchers have recently focused on the synthesis and characterization of M41S materials due to their high surface area and well-defined narrow pore size distribution in catalytic and adsorption studies. In this study, MCM-41 material, which is used to remove poisonous and corrosive H2S gases released from many industrial processes and causing acid rain, was investigated. In this work, pure MCM-41 was synthesized by using hidrothermal synthesis and reproducible samples were obtained under same conditions. In order to understand surfactant and silica source effects on material structure, synthesis of MCM-41 has repeated with different surfactants and silica sources. MCM-41 materials prepared in this work were characterized XRD, BET, EDS, XPS, TPR, SEM techniques. Four characteristic Bragg peaks of MCM-41 were observed in the XRD patterns of MCM-41. The surface area of these samples determined by BET analysis, changed between 1040 and 1219 m2/g. Then, copper incorporated MCM-41 catalysts were synthesized by using direct (hidrothermal) and impregnation methods with different Cu/Si ratios. In Cu- MCM-41 materials, copper was in CuO, tenorite, structure and MCM-41 structure was retained in each method. Also, when the amount of copper increased in the structure of copper-containing MCM-41 materials, an increase in CuO peak intensity and a decrease in surface area values were observed. In the last part of the study, desulfurization experiments were carried out using a fixed-bed reactor at 500oC, with a total flow rate of 100 cm3/min (1% H2S, 10% H2 and 89% He) using Cu-MCM-41 sorbents prepared in this work. The sulfur capture capacity of the sorbents was obtained. After desulfurization experiments surface area of Cu-MCM-41 decreased and CuO peaks disappeared in the XRD patterns. After desulfurization experiments, Cu1.81S peaks were observed in the XRD patterns of the Cu@MCM-41(I) synthesized by impregnation method.