A crystalline material contains oxygen, aluminum and phosphorus, and has powder X-ray diffraction peaks shown below. When the peak at 2θ=14.17±0.2° is used as the reference peak and the intensity of the reference peak is set to 100, for example, the relative intensity of the peak at 2θ=8.65±0.2° is 1 to 15. The relative intensity of the peak at 2θ=9.99±0.2° is 1 to 15. The relative intensity of the peak at 2θ=16.52±0.2° is 5 to 80. The relative intensity of the peak at 2θ=17.37±0.2° is 1 to 15. The relative intensity of the peak at 2θ=21.81±0.2° is 10 to 80.

A novel silicoaluminophosphate molecular sieve has a schematic chemical composition, expressed on a molar basis, of mSiO.sub.2.Math.Al.sub.2O.sub.3.Math.nP.sub.2O.sub.5, in which m represents the molar ratio of SiO.sub.2 to Al.sub.2O.sub.3 and is in a range of about 0.005-0.15, and n represents the molar ratio of P.sub.2O.sub.5 to Al.sub.2O.sub.3 and is in a range of about 0.7-1.1. The silicoaluminophosphate molecular sieve has a unique X-ray diffraction pattern, and can be used as an adsorbent, a catalyst or a catalyst carrier.

A novel silicoaluminophosphate molecular sieve has a schematic chemical composition, expressed on a molar basis, of mSiO.sub.2.Math.Al.sub.2O.sub.3.Math.nP.sub.2O.sub.5, in which m represents the molar ratio of SiO.sub.2 to Al.sub.2O.sub.3 and is in a range of about 0.005-0.15, and n represents the molar ratio of P.sub.2O.sub.5 to Al.sub.2O.sub.3 and is in a range of about 0.7-1.1. The silicoaluminophosphate molecular sieve has a unique X-ray diffraction pattern, and can be used as an adsorbent, a catalyst or a catalyst carrier.

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.sub.xAl.sub.yP.sub.z)O.sub.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.sub.xAl.sub.yP.sub.z)O.sub.2; and w=0.001˜0.124. The synthesized molecular sieve can be used as a catalyst for a selective reduction of NO.sub.x.

The present invention provides a long-lifetime SAPO-34 catalyst prepared from waste MTO catalyst as a raw material and a preparation method thereof. The method comprises the following steps: mixing the waste MTO catalyst fine powder with water; adding a phosphoric acid and an organic amine and stirring to obtain an initial gel mixture for SAPO-34 molecular sieve; crystallizing the initial gel mixture and then at least drying it to obtain a raw SAPO-34 molecular sieve powder; calcining the raw molecular sieve powder to obtain a SAPO-34 molecular sieve powder; then mixing it with a binder and a matrix carrier in water with stirring, and then aging it; and molding and then calcining it to obtain the long-lifetime SAPO-34 catalyst. The preparation method of the present invention uses MTO waste catalyst as a raw material to synthesize SAPO-34 molecular sieve in situ within a short time, and to prepare MTO catalysts having a long life and high selectivity for light olefins.

The present invention provides a long-lifetime SAPO-34 catalyst prepared from waste MTO catalyst as a raw material and a preparation method thereof. The method comprises the following steps: mixing the waste MTO catalyst fine powder with water; adding a phosphoric acid and an organic amine and stirring to obtain an initial gel mixture for SAPO-34 molecular sieve; crystallizing the initial gel mixture and then at least drying it to obtain a raw SAPO-34 molecular sieve powder; calcining the raw molecular sieve powder to obtain a SAPO-34 molecular sieve powder; then mixing it with a binder and a matrix carrier in water with stirring, and then aging it; and molding and then calcining it to obtain the long-lifetime SAPO-34 catalyst. The preparation method of the present invention uses MTO waste catalyst as a raw material to synthesize SAPO-34 molecular sieve in situ within a short time, and to prepare MTO catalysts having a long life and high selectivity for light olefins.

The invention relates to a method for synthesizing silicoaluminophosphate sorbents such as SAPO-56 and SAPO-47 comprising the use of a specific structure directing agent (SDA) comprising a mixture of different types of amines The structure providing agent (SDA) comprises N,N,N,N-tetramethyl-1,6-hexanediamine (TMHD) and a co-structure providing agent (co-SDA) selected among primary, secondary and tertiary amines comprising up to 15 carbon atoms and mixtures thereof. A preferred SDA comprises isopropylamine, dibutylamine and tripropylamine The sorbents are particularly suitable for up-grading biogas such as separating carbon dioxide from methane.

The invention relates to a method for synthesizing silicoaluminophosphate sorbents such as SAPO-56 and SAPO-47 comprising the use of a specific structure directing agent (SDA) comprising a mixture of different types of amines The structure providing agent (SDA) comprises N,N,N,N-tetramethyl-1,6-hexanediamine (TMHD) and a co-structure providing agent (co-SDA) selected among primary, secondary and tertiary amines comprising up to 15 carbon atoms and mixtures thereof. A preferred SDA comprises isopropylamine, dibutylamine and tripropylamine The sorbents are particularly suitable for up-grading biogas such as separating carbon dioxide from methane.

A method for synthesizing a nano SAPO-34 molecular sieve, and an SAPO-34 molecular sieve catalyst and application thereof. A nano SAPO-34 molecular sieve is synthesized by adding a microporous templating agent and a templating agent having a functionalized organic silane to hydrothermal synthesis. The nano SAPO-34 molecular sieve is calcined to obtain a nano SAPO-34 molecular sieve catalyst. The catalyst can be used in a reaction for preparing low-carbon olefin from an oxygen-containing compound. The nano SAPO-34 molecular sieve obtained by this method has a pure CHA crystal phase. Moreover, the nano SAPO-34 molecular sieve catalyst obtained by this method has good catalytic performance in a MTO reaction, the service life of the catalyst is significantly prolonged, and the selectivity of the low-carbon olefin is improved.

A process for preparing C.sub.2 to C.sub.3 olefins includes introducing a feed stream having a volumetric ratio of hydrogen to carbon monoxide from greater than 0.5:1 to less than 5:1 into a reactor, and contacting the feed stream with a bifunctional catalyst. The bifunctional catalyst includes a Cr/Zn oxide methanol synthesis component having a Cr to Zn molar ratio from greater than 1.0:1 to less than 2.15:1, and a SAPO-34 silicoaluminophosphate microporous crystalline material. The reactor operates at a temperature ranging from 350 C. to 450 C., and a pressure ranging from 10 bar (1.0 MPa) to 60 bar (6.0 MPa). The process has a cumulative productivity of C.sub.2 to C.sub.3 olefins greater than 15 kg C.sub.2 to C.sub.3 olefins/kg catalyst.