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Zeolite/alumina composite, and a method for making, the composite for use as a catalyst substrate or catalyst carrier and comprising zeolite having a silica/alumina ratio of greater than 300 and gamma alumina having a specific surface area of greater than 100 m 2 /g. The zeolite/alumina composite e

Zeolite/alumina composite, and a method for making, the composite for use as a catalyst substrate or catalyst carrier and comprising zeolite having a silica/alumina ratio of greater than 300 and gamma alumina having a specific surface area of greater than 100 m 2 /g. The zeolite/alumina composite exhibits a modulus of rupture of at least 750 psi. Additionally, the invention is also directed at a three catalyst (TWC) system for use in the removal of hydrocarbons, carbon monoxide and oxides of nitrogen from waste gas, the TWC system comprising the following components: (1) a zeolite/alumina composite catalyst support exhibiting a modulus of rupture of at least 750 psi and having a zeolite with a silica/zeolite ratio of at least 300 and the alumina comprising a gamma alumina having a specific surface area of greater than 100 m 2 /g; and, (2) a noble metal catalyst impregnated on the catalyst support, the noble metal selected from the group consisting of platinum, rhodium, iridium and palladium.

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1. A three-way catalyst (TWC) for use in the removal of hydrocarbons, carbon monoxide and oxides of nitrogen from waste gas, the TWC catalyst comprising:(1) a zeolite/alumina composite catalyst support exhibiting a modulus of rupture of at least 750 psi and comprising zeolite having a silica/alumina

1. A three-way catalyst (TWC) for use in the removal of hydrocarbons, carbon monoxide and oxides of nitrogen from waste gas, the TWC catalyst comprising:(1) a zeolite/alumina composite catalyst support exhibiting a modulus of rupture of at least 750 psi and comprising zeolite having a silica/alumina molar ratio of at least 300 and an alumina comprising a gamma alumina having a specific surface area of greater than 100 m 2 /g, and,(2) a noble metal catalyst impregnated on the catalyst support, the noble metal is selected from the group consisting of platinum, rhodium, iridium and palladium. 2. The TWC catalyst of claim 1 wherein the composite exhibits a modulus of rupture of at least 1000 psi. 3. The TWC catalyst of claim 1 wherein the catalyst system comprises between 5-60 g/ft 3 of noble metal catalyst. 4. The TWC catalyst of claim 1 wherein the catalyst system comprises a mixture of platinum and rhodium, the platinum/rhodium ratio ranging between about 5 to 10. 5. The TWC catalyst of claim 4 wherein the platinum is present in an amount of up to 40 g/ft 3 and the rhodium present in an amount up to 8 g/ft 3 . 6. The TWC catalyst of claim 4 wherein the platinum is present in an amount of 33.3 g/ft 3 and the rhodium is present in an amount of 6.6 g/ft 3 .