A green approach for simultaneously preparing Ti5Si3 and Ti5Si4-TiAl3 alloys using spent SCR catalyst, Ti-bearing blast furnace slag, and Al alloy scrap

Strategy and Technical Progress of Recycling of Spent Vanadium–Titanium-Based Selective Catalytic Reduction Catalysts

“…The purification of high-purity metal Ti elements or their use to prepare alloys and nanoultrafine powders has become a significant direction for the application of spent catalysts at present (Figure 18). Zhang et al 116 proposed an environmentally friendly and efficient method for the preparation of Ti 5 Si 3 and Ti 5 Si 4 −TiAl 3 alloys using spent SCR catalysts, Ti-containing blast furnace slag, and aluminum (Al) alloy scrap. Ti and Si were extracted from the spent catalyst and Ti-containing blast furnace slag using Al alloy scrap as the reducing agent under simultaneous production of the Ti−Si−Al alloy.…”

Existing state and solidification characteristics of heavy metals in glass‐ceramics from Mn‐bearing blast furnace slag

“…With the rapid development of the world industry and economy, the consumption of steel products has reached an extremely high level which result in large emission of blast furnace slag (BFS) 1–4 . As a result, a large amount of land resources are occupied, and the heavy metals in BFS make much damage to the environment and seriously threatens the human living space 5–8 . At present, the comprehensive utilization of BFS includes the preparation of cement, slag brick, silicon fertilizer and glass‐ceramic, 9–11 and so forth.…”

“…[1][2][3][4] As a result, a large amount of land resources are occupied, and the heavy metals in BFS make much damage to the environment and seriously threatens the human living space. [5][6][7][8] At present, the comprehensive utilization of BFS includes the preparation of cement, slag brick, silicon fertilizer and glass-ceramic, [9][10][11] and so forth. The preparation of slag glass-ceramics prepared from BFS not only consumes a large amount of industrial solid wastes, but also realize the solidification and stabilization of heavy metals.…”

Environmentally friendly approach for sustainable recycling of spent SCR catalysts and Al alloy scrap to prepare TiAl3 and low-Fe Al alloys

“…Recently, electromagnetic directional crystallization (a physical process in which no waste liquid or waste gas is discharged) has been used to purify and separate Ti–Si–Al alloys to prepare high-purity Ti 5 Si 3 , 23 high-purity TiSi 2 , and low-Fe Al–Si alloys. 24,25 This technology can effectively inhibit the formation of intermediate phases in Ti 5 Si 3 and TiSi 2 alloys and remove Fe, Mn, Ca, and Mg impurities in the alloys.…”

“…On the other hand, the cost of preparing TiAl 3 (SSC and AAS as raw materials and using the Al reduction-electromagnetic directional crystallization technology) also needs to be considered. In our previous research, 23 Ti 5 Si 3 alloys were prepared using Ti-bearing blast furnace slag, SSCs, and AAS as raw materials. The study found that the energy cost of preparing Ti 5 Si 3 by Al reduction-electromagnetic directional crystallization was slightly higher than that of the traditional smelting process; however, the cost of raw materials was reduced by nearly 80% compared with pure metal materials.…”