A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

The present invention relates to a process for preparing zeolite crystals continuously, comprising the continuous introduction of a composition capable of generating zeolite crystals into at least one crystallization reaction zone subjected to stirring means, giving said composition a flow characterized by a relative Reynolds number Re.sub.r of between 40 and 50 000, and the continuous recovery of the crystals formed according to a flow characterized by a net Reynolds number Re.sub.n of between 1 and 1500.

The present invention relates to a process for preparing zeolite crystals continuously, comprising the continuous introduction of a composition capable of generating zeolite crystals into at least one crystallization reaction zone subjected to stirring means, giving said composition a flow characterized by a relative Reynolds number Re.sub.r of between 40 and 50 000, and the continuous recovery of the crystals formed according to a flow characterized by a net Reynolds number Re.sub.n of between 1 and 1500.

A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

Zeolites having highly dispersed bimetallic clusters, uniformly distributed in size and composition, encapsulated therein are disclosed. Metal encapsulation and alloying is conferred by introducing ligated metal cation precursors into zeolite synthesis gels, which are subsequently crystallized hydrothermally to form zeolites with metal cations occluded in the pores. The ligated cations are anchored to the zeolite framework via siloxane bridges which enforces their uniform dispersion throughout the zeolite crystals. Treatment of the crystallized zeolites in O.sub.2 and then H.sub.2 forms bimetallic clusters, which remain narrowly distributed in size and composition.

Lithium ion-exchanged zeolite particles and methods of making such lithium ion-exchanged zeolite particles are provided herein. The method includes combining precursor zeolite particles with (NH.sub.4).sub.3PO.sub.4 to form a first mixture including intermediate zeolite particles including NH.sub.4.sub.+ cations. The method further includes adding a lithium salt to the first mixture to form the lithium ion-exchanged zeolite particles, or separating the intermediate zeolite particle from the first mixture and combining the intermediate zeolite particles with the lithium salt to form the lithium ion-exchanged zeolite particles.

Lithium ion-exchanged zeolite particles and methods of making such lithium ion-exchanged zeolite particles are provided herein. The method includes combining precursor zeolite particles with (NH.sub.4).sub.3PO.sub.4 to form a first mixture including intermediate zeolite particles including NH.sub.4.sub.+ cations. The method further includes adding a lithium salt to the first mixture to form the lithium ion-exchanged zeolite particles, or separating the intermediate zeolite particle from the first mixture and combining the intermediate zeolite particles with the lithium salt to form the lithium ion-exchanged zeolite particles.

A separation membrane structure includes a porous support, a first separation membrane and a second separation membrane. The first separation membrane is formed on the porous support and contains high silica zeolite having Si/Al atomic ratio of greater than or equal to 200. The second separation membrane is formed on the first separation membrane and contains cation.

A separation membrane structure includes a porous support, a first separation membrane and a second separation membrane. The first separation membrane is formed on the porous support and contains high silica zeolite having Si/Al atomic ratio of greater than or equal to 200. The second separation membrane is formed on the first separation membrane and contains cation.