Crystalline zeolite LZ-202 and process for preparing same

Claim 2

A crystalline omega-type synthetic zeolite molecular sieve, denominated LZ-202, (a) whose stoichiometric composition expressed in moles of oxide is 1.0±0.5M.sub.2 /.sub.n O:Al.sub.2 O.sub.3 :xSiO.sub.2 :yH.sub.2 O wherein M represents at least one hydrogen, ammonium, alkali metal, alkaline earth, transition metal or rare earth lanthanide metal cation in oxidation state n, x has a value of from about 3 to about 20, and y has a value of from zero to about 20; (b) having an X-ray diffraction pattern characteristic of an omega-type zeolite; (c) whose fluorosilicate substitution product is more crystalline than that prepared from a calcined or oxidized omega-type zeolite synthesized using an organic template cation.

Claim 3

The crystalline zeolitic molecular sieve of claim 1 wherein M is sodium, hydrogen, ammonium or potassium.

Claim 4

The crystalline zeolitic molecular sieve of claim 1 wherein x is from about 5 to about 10 and y is from 0 to 10.

Claim 5

A molecular sieve according to claim 1 wherein said fluorosilicate substitution product is more than 30% crystalline relative to calcined, then ammonium-exchanged zeolite omega.

Claim 6

A molecular sieve according to claim 4 wherein said fluorosilicate product is at least 75% crystalline.

Claim 7

An organic template-free method of preparing LZ-202 which comprises: (a) combining, with sufficient agitation to maintain an organic template-free slurry, (i) an aqueous solution of an aluminum salt containing the anion of a strong acid, and (ii) an aqueous solution of MOH of sufficient concentration and amount to neutralize said aluminum salt, wherein MOH is an alkali metal hydroxide; (b) blending with said organic template-free slurry of step (a) a silica source containing silica in a molar amount that is about 5 to about 30 times that of alumina and an alkali metal source in a molar amount that is about 1 to about 12 times that of alumina; and (c) digesting the mixture of step (b) for a time and at a temperature sufficient to produce a crystalline material having an X-ray diffraction pattern characteristic of omega-type zeolites.

Claim 8

An organic template-free method of preparing LZ-202 which comprises: (a) combining, with sufficient agitation to maintain an organic template-free slurry, (i) an aqueous solution of an aluminum salt containing the anion of a strong acid, and (ii) an aqueous solution of MOH of sufficient concentration and amount to neutralize said aluminum salt, wherein MOH is an alkali metal hydroxide; (b) blending with said organic template-free slurry of step (a) a silica source containing silica in a molar amount that is about 5 to about 30 times that of alumina and an alkali metal source in a molar amount that is about 1 to about 12 times that of alumina; and (c) digesting the mixture of step (b) for a time and at a temperature sufficient to produce a crystalline material having an X-ray diffraction pattern characteristic of omega-type zeolites.

Claim 9

A method according to claim 6 wherein said solution of aluminum salt is added to said solution of MOH.

Claim 10

A method according to claim 6 wherein said aluminum salt is an aluminum sulfate.

Claim 11

A method according to claim 6 wherein M is sodium.

Claim 12

A method according to claim 6 where said metal-silica source contains silica in a molar amount that is about 6 to about 10 times that of alumina added in step a.

Claim 13

A method according to claim 6 wherein said metal-silica source contains silica in a molar amount that is about 8.0 to about 8.2 times that of alumina added in step a.

Claim 14

A method according to claim 6 wherein said metal-silica source contains alkali metal in a molar amount that is about 1.5 to about 4 times that of alumina added in step a.

Claim 15

A method according to claim 6 wherein said metal-silica source contains alkali metal in a molar amount that is about 2.4 to about 2.7 times that of the alumina added in step a.

Claim 16

A method according to claim 6 wherein said metal-silica source is an alkali metal silicate containing from about 15 to about 40 percent by weight SiO 2 and from about 5 about 15 percent by weight M 2 O.

Claim 17

A method according to claim 14 wherein said metal-silica source is sodium silicate containing from about 25 to about 35% by weight SiO 2 and from about 6 to about 12% by weight Na 2 O.

Claim 18

A method according to claim 14 wherein said sodium silicate contains from about 28 to about 32 percent by weight SiO 2 and from about 8 to about 10 percent by weight Na 2 O.

Claim 19

A method according to claim 6 which further comprises aging the product of step b for about 10 to about 30 hours at a temperature of from about 0° C. to about 50° C. prior to digestion.

Claim 20

A method according to claim 6 which further comprises mixing a promoter with the aluminum salt solution, the MOH solution or the alkali metal and silica sources or with the products of either step (a) or step (b), wherein said promoter provides centers around which zeolite LZ-202 can grow.

Claim 21

A method according to claim 18 wherein said promoter is a powder containing fine crystals of an omega-type zeolite or a partially digested precursor suspension for an omega-type zeolite.

Claim 22

A method according to claim 18 wherein said promoter is LZ-202, calcined or uncalcined zeolite omega or calcined or uncalcined zeolite ZSM-4.

Claim 23

A method according to claim 18 wherein the weight of said promoter is about 0.1 to about 15 percent of the weight of the reaction mixture when the promoter is a crystalline powder.

Claim 24

A method according to claim 18 wherein the weight of said promoter is about two to about six percent of the weight of the reaction mixture when the promoter is a fine crystalline powder and the metal-silica source is sodium silicate.

Claim 27

A method according to claim 23 wherein said sodium silicate contains from about 28 to about 32 percent by weight of SiO 2 and from about 8 to about 10 percent by weight of Na 2 O.

Claim 28

A method according to claim 23 wherein the product of step b is digested quiescently at about 90° C. to about 110° C.

Claim 29

A method according to claim 23 wherein the composition of the blend resulting in step b is, in terms of moles of oxides and sulfate: Al 2 O 3 : 5-30 SiO 2 : 1-5 Na 2 O: 3-20 Na 2 SO 4 : 50-1,000 H 2 O.

Claim 30

A method according to claim 26 wherein said composition is Al 2 O 3 : 6-12 SiO 2 : 2-3 Na 2 O: 3-5 Na 2 SO 4 : 100-200 H 2 O.

Claim 31

A method according to claim 26 wherein said composition is Al 2 O 3 : 8.0-8.2 SiO 2 : 2.4-2.7 Na 2 O: 3.0 Na 2 SO 4 : 150-170 H 2 O.

Claim 32

A method according to claim 23 which further comprises mixing promoter with said aluminum salt, said MOH or said sodium silicate or with the products of either step a or step b.

Claim 33

A method according to claim 29 wherein aid promoter is a powder containing fine crystals of an omega-type zeolite or a precursor suspension for an omega-type zeolite.

Claim 34

A method according to claim 30 wherein said promoter is LZ-202, calcined or uncalcined zeolite omega or calcined or uncalcined zeolite ZSM-4.

Claim 35

A method according to claim 29 wherein the weight of said promoter is about 0.1 to about 15 percent of the weight of the reaction mixture when the promoter is a crystalline powder.

Claim 36

A method according to claim 29 wherein the weight of said promoter is about two to about six percent of the weight of the reaction mixture when the promoter is a fine crystalline powder and the metal-silica source is sodium silicate.

Claim 37

A method according to claim 23 wherein said promoter is a precursor suspension for an omega-type zeolite.

Claim 40

A method according to claim 35 wherein said sodium silicate contains from about 28 to about 32 percent by weight SiO 2 and from about 8 to about 10 percent by weight Na 2 O.

Claim 41

A method according to claim 35 wherein the digestion is conducted at a temperature of from about 90° C. to about 150° C.

Claim 42

A method according to claim 35 wherein the composition of the blend resulting in step b is, in terms of moles of oxides and sulfate: Al 2 O 3 : 5-30 SiO 2 : 1-5 Na 2 O: 3-20 Na 2 SO 2 : 50-1000 H 2 O.

Claim 43

A method according to claim 38 wherein said composition is Al 2 O 3 : 6-12 SiO 2 : 2-3 Na 2 O: 3-5 Na 2 SO 4 : 100-200 H 2 O.

Claim 44

A method according to claim 39 wherein said composition is Al 2 O 3 : 8.0-8.2 SiO 2 : 2.4-2.7 Na 2 O: 3.0 Na 2 SO 4 : 150-170 H 2 O.

Claim 45

A method according to claim 35 wherein said promoter is a powder containing fine crystals of an omega-type zeolite or a precursor suspension for an omega-type zeolite.

Claim 46

A method according to claim 35 wherein said promoter is LZ-202, calcined zeolite omega or calcined or uncalcined zeolite ZSM-4.

Claim 47

A method according to claim 35 wherein the weight of said promoter is about 0.1 to about 15 percent of the weight of the reaction mixture when the promoter is a crystalline powder.

Claim 48

A method according to claim 35 wherein said promoter is precursor suspension for an omega-type zeolite.

Claim 49

A method according to claim 35 wherein the weight of said promoter is about two to about six percent by weight of the reaction mixture when the promoter is a fine crystalline powder and the metal-silica source is sodium silicate.

Claim 50

A composition prepared by the method of claim 6.

Claim 51

A composition prepared by the method of claim 23.

Claim 52

A composition prepared by the method of claim 35.

Claim 53

The LZ-202 zeolite of claim 1 characterized by the following X-ray diffraction pattern: ______________________________________ d(A) Relative Intensity ______________________________________ 15.54 M 9.06 VS 7.83 M 6.81 MS 5.93 M 4.68 M 3.79 MS 3.70 M 3.61 M 3.51 S 3.15 S 3.08 M 3.02 M 2.91 S ______________________________________

Claim 54

The method for preparing LZ-202 zeolite of claim 6 wherein said crystalline material is characterized by the following X-ray diffraction pattern: ______________________________________ d(A) Relative Intensity ______________________________________ 15.54 M 9.06 VS 7.83 M 6.81 MS 5.93 M 4.68 M 3.79 MS 3.70 M 3.61 M 3.51 S 3.15 S 3.08 M 3.02 M 2.91 S ______________________________________