Spotlight on Cu/SAPO-34 with high hydrothermal stability induced by a small amount of SSZ-39

Selective catalytic reduction of NOx with NH3 over copper-based catalysts: recent advances and future prospects

“…Moreover, stable SSZ-39 seeds were introduced to the precursors of SAPO-34 to synthesize the composite structure of SAPO-34 + SSZ-39 materials (SA + SZ). 124 With the modification of SSZ-39 zeolites, the interface of the Cu/(SA + SZ) samples induced higher contents of stable Si(nOAl) (n = 0, 1) structures and acid sites, accompanied by the formation of more Cu isolated species (Fig. 9f).…”

“…Although Cu-SAPO-34 zeolites with CHA framework topology have garnered considerable attention because of the remarkable NH 3 -SCR performance across a broad operating temperature range and high-temperature hydrothermal stability, 90,91 the crystallinity of Cu-SAPO-34 zeolites tended to decline during the process of traditional metal ion loading in the repeated ion exchange. The other main issue arrived when copper-tetraethylenepentamine (Cu-TPEA) was used as the structure-directing agent, as it often led to the production of high Si contents and numerous Si islands on Cu-SAPO-34 through the one-pot method, significantly reducing the catalytic activity and hydrothermal stability.…”

NOx reduction against sulfur poisoning by using Ce-modified Cu-SAPO-34 catalysts

“…[7][8][9] Lin et al used a small amount of SSZ-39 to fasten the more active Cu 2+ to Cu-SAPO-34 to improve the hydrothermal stability of the hybrid catalyst. 10 Hence, a large quantity of research on CHAtype zeolites for NH 3 -SCR which is largely related to metal modification and mechanism exploration has emerged in recent years. 11,12 Compared to SSZ-13, SAPO-34 has attracted greater attention because of its lower cost.…”

Studies of NO Reduction with Ammonia Over Copper Species Deposited on MCM‐41 Nanospheres ‐ Experimental Evidence of Reaction Mechanism

“…Low-temperature activity in the NH 3 -SCR has been reported for various catalyst systems, including char-based materials [5,6,7] and zeolites modified with transition metals. [8,9,10] To transition metals catalytically active in the low-temperature reduction of nitrogen oxides belong, among others, copper [9,11,12] and manganese, [13,14,15] used as main catalytically active components or in combinations with other metals, e. g., Cu-Fe, [16] Cu-Ce, [17] Mn-Ce, [18] Mn-Co. [19] Catalytic performance of the NH 3 -SCR catalysts strongly depends on the form and aggregation of catalytically active transition metal species as well as properties of the used catalytic support, such as surface acidity [20] or porosity. [21] Recently, a very promising catalytic performance in the lowtemperature NH 3 -SCR process has been reported for copper modified mesoporous silicas obtained by template ion-exchange (TIE) method.…”