講演情報
[PE1-075]Recycle of Vanadium from waste SCR catalysts by series ion exchange column
○Zi-Wei Yeh1, Ya-Yun Shih1, Yun-Hwei Shen1 (1. National Cheng Kung University)
Selective catalytic reduction (SCR) is widely used in steel industry to remove NOx in exhaust gas treatment because of its great efficiency. The lifespan of SCR is about 2 years. It is estimated that there is more than 1,000 tons of waste SCR annually in Taiwan. The main chemical composition of waste SCR is 0.58 wt% V, 0.73wt% As,68.96wt% Ti, 17.16 wt% Si,4.79wt% Mo, 3.81wt% Fe, 3.45wt% Al, 0.46wt% P, 0.04wt% Ca, 0.02wt% W.
In this experiment, the waste SCR was subjected to alkali roasting, hot water leaching and the series ion exchange column. 98% of Vanadium was leached out through alkali roasting and hot water leaching. For series ion exchange columns, the optimal pH and flow rate were 8 and 5.5BV/Hr to separate Vanadium and Arsenic. The optimal desorption agent and flow rate were 5N NH4OH + 2N NH4CL and 0.92BV/Hr, where Vanadium and Arsenic were 99.7% and 0% desorbed. Finally, rotary evaporator was chosen to crystallize into NH4VO3. The purity of final product is 99.5% with no As detected.
In this experiment, the waste SCR was subjected to alkali roasting, hot water leaching and the series ion exchange column. 98% of Vanadium was leached out through alkali roasting and hot water leaching. For series ion exchange columns, the optimal pH and flow rate were 8 and 5.5BV/Hr to separate Vanadium and Arsenic. The optimal desorption agent and flow rate were 5N NH4OH + 2N NH4CL and 0.92BV/Hr, where Vanadium and Arsenic were 99.7% and 0% desorbed. Finally, rotary evaporator was chosen to crystallize into NH4VO3. The purity of final product is 99.5% with no As detected.