SO₂ Storage by CuTa₂O₆: Synergetic Oxidative Sorption

Abstract

SO₂ storage was performed on CuTa₂O₆ and its derivatives by repeating the cycle of oxidative sorption (SO₂, 1000 ppm; O₂, 3%) and reductive desorption (H₂, 10%). Tantalum promoted the sorption of SO₂ on CuTa₂O₆, and the synergetic oxidative sorption of copper and tantalum was investigated after several cycles. Observation of the specific surface areas of samples revealed that SO₂ was absorbed also in the bulk of catalysts through synergetic oxidative sorption. XRD observation showed that the samples undergoing synergetic oxidative sorption were amorphous. Through observation of ammonia-TPD, it was found that the samples were comparable to super acid. Synergetic oxidative sorption was investigated on the physical mixture of copper oxide and tantalum oxide, as well as on the mixed oxides of CuO and MO (M = Nb, Cr, Ti and Zr).