Study on the Regeneration of Copper-Manganese Sorbent for Removal of Sulfur Dioxide from Flue Gases

摘要

The work is part of a study on the development of a new method for simultaneous removal of nitrogen oxide (NO) and sulfur dioxide (SO_2) from flue gases. The concept is based on a mixture of active components with two different functions: sorption of SO_2 by silica-supported copper-(Ⅱ) oxide (CuO) and manganese(Ⅳ) oxide (MnO_2) and selective catalytic reduction (SCR) of NO with ammonia (NH_3) in the presence of vanadium(Ⅴ) oxide (V_2O_5). The paper is focused on the reductive regeneration of mixtures of sulfates of manganese and copper, which are formed in the desulfurization step. The reduction of pure unsupported MnSO_4 with hydrogen requires a higher temperature than that for CuSO_4. Of principal interest for this study is the possibility to decrease the temperature for the reduction of MnSO_4 in order to facilitate the simultaneous regeneration of the sulfates in the sorbent. The results show that under the selected experimental conditions the temperature for the reduction of the sulfated MnO_2 in the desulfurization sorbents may be significantly lower compared to the temperature for pure MnSO_4.