摘要:
Disclosed are a Cu-SAPO molecular sieve with coexisting crystal phases of CHA and GME, a synthesis process therefor and the use thereof in a denitration reaction. A XRD diffraction pattern of the Cu-SAPO molecular sieve shows the characteristic of broad peaks and narrow peaks coexisting. An inorganic framework has the following chemical composition: wCu-(Si x Al y P z )O 2 , wherein x, y and z respectively represent the molar fractions of Si, Al and P; the molar fraction ranges thereof are respectively x = 0.01∼0.28, y = 0.35∼0.55 and z = 0.28∼0.50, with x+y+z = 1; w is the molar number of Cu per mole of (Si x Al y P z )O 2 ; and w = 0.001∼0.124. The synthesized molecular sieve can be used as a catalyst for a selective reduction of NO x .
摘要:
A preparation method for a metal-modified SAPO molecular sieve is disclosed, characterized in adding a raw powder of the SAPO molecular sieve to a solution containing metal ions for performing ion exchange, and then washing and drying the obtained solid after ion exchange, so as to obtain the metal-modified SAPO molecular sieve. The metal-modified SAPO molecular sieve prepared has a relatively high degree of crystallinity, and the metal elements occupy the ionic positions in the channels and/or cages of the SAPO molecular sieve, and the metal-modified SAPO molecular sieve shows excellent catalytic performance in the catalytic reaction.
摘要:
A solvothermal synthesis process of the SAPO molecular sieves and catalysts prepared thereby are provided. The synthesis process comprises the following steps: a) an organic amine, an aluminum source, a phosphorus source, a silicon source, and water are mixed in a molar ratio of 6-30 : 1 : 0.5-5 : 0.01-1.0 : 0.1-15, to obtain an initial mixture for preparing the SAPO molecular sieves, wherein the molar ratio of water to the organic amine is less than 2.0; b) the initial mixture obtained in the step a) is maintained at 30-60 °C and aged with stirring for not more than 24 hours, to obtain an initial gel; c) the initial gel obtain in the step b) is crystallized at 150-250 °C for 0.5-15 days. The SAPO molecular sieves prepared thereby are used, after being calcined at 400 - 700 °C in air, as catalysts for acid-catalyzed reactions or for conversion reactions of oxygen-containing compounds to olefins.
摘要:
A porous crystalline silico-alumino-phosphate molecular sieve is described. The molecular sieve has a framework composition on an anhydrous and calcined basis expressed by an empirical formula (SixAlyPz)O2 where x is the mole fraction of Si and has a value from 0.001 to about 0.5, y is the mole fraction of Al and has a value of at least 0.01, z is the mole fraction of P has a value of at least 0.01, and x+y+z=1, where the molecular sieve is characterized as having a LTA framework with an average crystal size of less than 5 micrometers. Methods of making the molecular sieves are also described.
摘要:
A honeycomb structure of the invention includes a honeycomb unit provided with a plurality of through holes arrayed in a longitudinal direction with a partition wall therebetween, in which the honeycomb unit is produced by extruding and firing raw material paste containing silicoaluminophosphate particles and an inorganic binder, and the silicoaluminophosphate particles have a specific surface area in a range of 200 m 2 /g to 400 m 2 /g, and an acid point of 1.2 mmol/g or more.