SSZ-13
SSZ-13 (framework type code CHA) is an aluminosilicate zeolite mineral possessing 0.38 × 0.38 nm micropores. It belongs to the ABC-6 family of zeolites as well as offretite, cancrinite, erionite and other related minerals. The framework topology is the same as that of chabazite but SSZ-13 has a high silica composition with Si/Al > 5, which leads to low cation exchange capacity. The typical chemical formula of the unit cell can be described as QNaAlSiO•"z"HO (1.4 < "x" <27)(0.7 < "y" < 4.3)(1 < "z" <7), where Q is "N","N","N"-1-trimethyladamantammonium. The material was patented by  Chevron research Company in 1985, and could potentially be used as a solid catalyst for the methanol-to-olefins (MTO) process and the selective catalytic reduction (SCR) of NOx. Synthesis. SSZ-13 can be synthesized using the following method. The material is prepared from the following batch composition: 10 NaO : 2.5 AlO : 100 SiO : 4400 HO : 20 TMAdOH. 2 g 1N NaOH, 2,78 g 0.72 M "N","N","N"-1-trimethyladamantammonium hydroxide (TMAdOH) and 3.22 g deionized water are mixed. 0,1 g AlO is added to the solution and mixed with 0.6 g fumed silica. The resulting viscous gel is aged for two hours  and heated for 4 days at 160 °C in a Teflon lined steel autoclave. The crystallized product can be recovered by filtration. Submicron-sized SSZ-13 can be prepared in 6 hours through a rapid steam-assisted crystallization method using tetraethyl orthosilicate (TEOS) as the silica source. Uses. SSZ-13 is a high-silica zeolite with the CHA topology. Materials with this topology are of industrial interest, as potential catalysts for application in the methanol to olefins (MTO) reaction. Recently SSZ-13 has attracted attention as the catalyst for selective catalytic reduction (SCR) of NOx. Actually copper-loading SSZ-13 is industrially applied  to the emission control of diesel engines.