Low-cost V-W-Ti SCR catalyst from titanium-bearing blast furnace slag

Preparing SCR (selective catalytic reduction) catalyst from the titanium-bearing blast furnace slag not only realized the high-value utilization of the slag but also provided a low-cost method for V-W-Ti catalyst production. Titanium dioxide was extracted from titanium-bearing blast furnace slag and used as the carrier of V-W-Ti SCR catalyst. Although with 21% SiO2 and a little Al and Fe impurities, the slag-based SCR catalyst exhibited higher deNO(x) activity and wider active temperature range than commercial TiO2-based catalysts. Under the conditions of NO = 600 ppm, GHSV (gas hourly space velocity) = 24,000 h(-1), NH3/NO = 0.8 and O-2 = 3%, the slag-based SCR catalyst exhibited NO conversion of higher than 77% in the temperature range of 250-450 degrees C. For a test at 300 degrees C, the slag-based catalyst also showed outstanding catalytic stability in the flue gas containing 2000 ppm SO2 and 10% H2O. (C) 2014 Elsevier Ltd. All rights reserved.