Regenerated catalytic powder prepared from abandoned vanadium-based SCR (selective catalytic reduction) catalyst and method for preparing regenerated catalytic powder

Abstract

The invention discloses regenerated catalytic powder prepared from an abandoned vanadium-based SCR (selective catalytic reduction) catalyst and a preparation method of the regenerated catalytic powder. The method comprises the following steps: first, adding alkaline liquor into an ash-removed and pulverized abandoned vanadium-based SCR catalyst, agitating an obtained mixture I, carrying out a reaction on the agitated mixture I, filtering and water-scrubbing a reaction product, afterwards, washing a filter cake to be neutral with acid liquor to obtain TiO2, next, adding a vanadium salt and a tungsten salt into the TiO2, uniformly mixing an obtained mixture II, and then roasting and ball-milling the obtained mixture II to obtain the regenerated catalytic powder of which the particle sizes D50 are equal to 1-20 microns; the powder contains the following components: 0.1-5%wt of V205, 80-98%wt of the TiO2 and 1-10%wt of WO3. The method provided by the invention removes agglomerated and inactivated vanadium and tungsten substances from the abandoned vanadium-based SCR catalyst through cleaning, then adds some active substances into the abandoned vanadium-based SCR catalyst again, carries out roasting and ball-milling, and not only solves the sintering agglomeration of active components, enables that the newly added active substances can be favorably dispersed, but also solves the problem that a catalyst cannot be regenerated due to the reduction of mechanical strength or fragmentation; further, the preparation method is succinct in process, easy to control in conditions, and suitable for large-lot production.

Description

technical field [0001] The invention belongs to the technical field of regenerated catalytic powder and its preparation method, and in particular relates to a regenerated catalytic powder prepared by using a waste vanadium-based SCR catalyst and a method thereof. Background technique [0002] By the end of 2015, the total number of selective reduction and denitration catalyst (SCR) implementation projects completed nationwide will reach 670 million kw. A large number of denitration catalysts have been used in these projects, and most of them are vanadium-based SCR catalysts. As we all know, the service life of vanadium-based SCR catalysts is relatively short, and generally deactivates in about 3 years and needs to be replaced. However, because the vanadium in the deactivated vanadium-based SCR catalyst has strong biological toxicity, the disposal of the spent vanadium-based SCR catalyst has become a difficult problem. For this reason, the "Technical Policy for the Preventio...

AI Technical Summary

Problems solved by technology

However, the deactivation of vanadium-based SCR catalysts is often accompanied by severe sintering, that is, the vanadium and tungsten species in the catalyst have aggregated into clusters and crystals from a fresh state of good dispersion, and the dispersibility is severely reduced, which leads to its catalytic degradation. The activity is significantly reduced; and the accumulation of vanadium species will further lead to SO 2 Increased oxidation rate, affecting durability of regenerated catalyst

Therefore, if the catalyst that has been used for a long time and is accompanied by severe sintering is ground and added to the new catalyst prepared as part of the raw material, it will cause the newly added active components to further aggregate into the ground old catalyst during the preparation process. In the agglomeration of materials, the deterioration of performance is accelerated—that is, the agglomeration phenomenon is aggravated, so that SO 2 The oxidation rate is further increased, and the service life is further shortened