METHOD FOR PREPARING METALLOALUMINOPHOSPHATE (MEAPO) MOLECULAR SIEVE

摘要

The present invention also relates to a method for preparing metalloaluminophosphate (MeAPO) molecular sieve said method comprising :
a) forming a reaction mixture containing a texture influencing agent (TIA), an organic templating agent (TEMP), at least a reactive inorganic source of MeO 2 insoluble in the TIA, reactive sources of Al 2 O 3 and P 2 O 5 ,
b) crystallizing the above reaction mixture thus formed until crystals of the metalloaluminophosphate are formed,
c) recovering a solid reaction product,
d) washing it with water to remove the TIA and
e) calcinating it to remove the organic template. In a usual embodiment said reaction mixture has a composition expressed in terms of molar oxide ratios of :
TEMP/Al 2 O 3 = 0.3-5 , more desirable 0.5-2
MeO 2 /Al 2 O 3 = 0.005-2.0, more desirable 0.022-0.8
P 2 O 5 /Al 2 O 3 =0.5-2, more desirable 0.8-1.2
TIA/Al 2 O 3 = 3-30, more desirable 6-20 In a usual embodiment the metalloaluminophosphate (MeAPO) molecular sieves made with the above method have a lamellar crystal morphology having an empirical chemical composition on an anhydrous basis, after synthesis and calcination, expressed by the formula H x Me y Al z P k O 2 wherein, y+z+k=1, x<=y
y has a value ranging from 0.0008 to 0.4 and more desirable from 0.005 to 0.18
z has a value ranging from 0.25 to 0.67 and more desirable from 0.38 to 0.55
k has a value ranging from 0.2 to 0.67 and more desirable from 0.36 to 0.54
said molecular sieve having predominantly a plate crystal morphology. In an advantageous embodiment the MeAPO made by the method of the invention have essentially a structure CHA or AEI or a mixture thereof. Preferably they have essentially the structure SAPO 18 or SAPO 34 or a mixture thereof.
The present invention also relates to catalysts consisting of the above MeAPO molecular sieves made by the method of the invention or comprising the above MeAPO molecular sieves made by the method of the invention. The present invention also relates to a process for making an olefin product from an oxygen-containing, halogenide-containing or sulphur-containing organic feedstock wherein said oxygen-containing, halogenide-containing or sulphur-containing organic feedstock is contacted with the above catalyst under conditions effective to convert the oxygen-containing, halogenide-containing or sulphur-containing organic feedstock to olefin products.