Introduction Selective catalytic reduction (SCR) of NOx with ammonia using metal-exchanged zeolites is now being commercialized on diesel vehicles.In the 1980s, American chemist Zones SI [1] synthesized a new molecular sieve SSZ-13 by hydrothermal method.Research shows SSZ-13 zeolite molecular sieve has high catalytic activity and hydrothermal stability[2].The high activity of these catalysts can be attributed to the large surface area and high loading of active components.Recently, with the application of in hydrothermal synthesis technology, molecular sieves were directly synthesized in cordierite monolithic carriers.Monolithic catalyst not only avoid the loss of the catalyst and secondary pollution to the environment, but also help the active metal became easier to enter the zeolite channels, thus result in high dispersion, fixed position and other characteristics.Experimental Cu-SSZ-13/cordierite is prepared by the traditional hydrothermal method with anhydrous cupric sulfate, silica sol, sodium metaaluminate, sodium hydroxide and deionized water as raw material of the SSZ molecular sieve, the complex of CuSO4· 5H2O with tetraethylene pentamine [3] as a template.Mix SiO2, Al2O3, Na2O, H2O and Cu-TEPA uniformly in the ratio of 10∶1∶2.6∶100∶ 2.0~2.5, then pour the mixture into a PTFE-lined high-pressure reactor with a piece of cordierite (17× 17 × 17 mm, 200 cpsi) in its bottom, and crystallize at 140 ℃ with the different crystallization time.After completion of the reaction, the product was washed, dried at 100 ℃ for 12 h and ion exchanged with a certain amount of ammonium nitrate for 12 hours, lastly, calcinated at 550 ℃ for removing the template and water.The activities of the Cu-SSZ-13/cordierite catalyst for the SCR reaction of NOx by NH3 at atmospheric pressure were determined using a fixed-bed flow microreactor, the total flow rate was 400 ml/min.The inlet concentration of NO, NO2 and O2 were analyzed by a flue gas analyzer (British, Kane-9106).And the product gas was analyzed online using a gas chromatograph equipped with two TCD detectors and two serial columns (a Porapak Q column served for separation of N2O and CO2, and a 5A Molecular Sieve column for separation of N2 and O2).Results and discussion The main characteristic peaks associated with CHA-type zeolite at 9.5°, 14.0°, 16.1°, 17.8°, 20.7°, 25.0° are detected when the crystallization time is from 24 to 108 h.And the corresponding CuSSZ-13/cordierite had been done and not been shown here.