CA1086293A - Process for preparing synthetic ferrierite - Google Patents

Abstract

PROCESS FOR PREPARING
SYNTHETIC FERRIERITE

Abstract of the Disclosure An improved process for preparing synthetic ferrierites having the absorption and catalytic properties characteristic of 5 to 8 angstrom zeolites which comprises promoting by a reaction mixture composed of salts of Group I and Group II cations of the periodic table with lithium salts. The promoted reaction mixture is seeded with natural or synthetic ferrierite seeds, and heated to con-vert the mass to the synthetic ferrierite.
The product has the emperieal formula, 0?1 to 0?9 Li2O:0O?1:O?9 R2O:Al2O3:6 to 25 SiO2 wherein R2O is Na2O, K2O, or Rb2O and/or Cs2O. 0?1 to 0?9 Li2O:
0?1 to 0?9 MO:A12O3:6 to 25 SiO2 wherein MO is BaO, CaO, MgO or SrO, or (Li2O:R2O:WO):Al2O3:6-25 SiO2 where R2O is any R2O above and MO is any MO above.

Description

1~86;~93 . ................................................................. .

This invention relates to the production of synthetic, crystalline ferrierite, an alumino-silicate zeolite. Ferrierite is relatively scarce in nature, but has been found in large deposits in the Western United States. Natural ferrierite has the general formula (Na,K)0 5_4 Ca0_1 Mg0.s_3 (A14_7 Fe0_1 Si27_3J 72 where the sum of the moles of alkali and alkaline earth oxides equal the sum of the moles of alumina and ferria, ~(Na2O ~ K2O + CaO +MgO) ~ ~(~12O3 + Fe2O3), and ~ (Si + A1 + Fe) = 36. Natural ferrierite from Kamloops Lake, British Columbia, Canada has been shown by P. A. Vaughan, Acta Crystallographica 21, 983 (1966), to be orthorhombic with the space group I 2/M 2/M 2/M. Natural ferrierites from various localities do not have exactly the same X-ray powder pattern, but X-ray powder pattern of ferrierite from each locality fits the theoretically allowed lines for the space group 2/M, 2/M, 2/M, as shown below in Table A, and the differences are presumably caused by variable cation contents. Synthetic strontium ferrierites of the approximate composition SrO:A12O3: 7-9 SiO2, the X-ray powder patterns of which also fit the allowed lines, have been described in the literature by R.M. Barrer and D.J. Marshall, Journal of the Chemical Society 1964. 485. Synthetic strontium and calcium ferrierite were made at 350-370C and 1,020-1,632 atmospheres by D. B. Hawkins, Materials Research Bulletin, 2 951 (1967). Also, synthetic sodium ferrierite was made by E.E. Senderov, Geochemistry (English Translation) 9. 848 (1963). Synthesis of strontium ferrierites by Barrer and Marshall were carried out at tempera-tures of 260, 340 and 380C at pressures of 39, 144 and 235 ~
30 atmospheres, respectively. Even though such high temperatures ~`

- 2 - _ i 1!D86;~93 as 340 and 380 were employed, the synthesis of strontium fer-rierite required 2-4 days. Twenty days were required to crystal-lize strontium ferrierite from a 1.5 SrO:1.0 A12O3: 9SiO2: 500H20 slurry at 260C.
The syntheses of strontium ferrierite, reported by Barrer and Marshall, at 340 and 380 C are relatively difficult, and the product ferrierite is frequently contaminated with impurities.
By using the seeding technique, described below, we have reduced the temperatures, pressures and times required for synthesis;
also we have greatly improved the reliability of the process.
Furthermore, no natural ferrierite has been shown to con-tain substantial amounts of strontium or lithium or both. Table B shows that samples of natural ferrierite from five localities are mainly sodium, potassium, magnesium, calcium aluminosilicate hydrates, with some possible substitution of iron for aluminum.
The compositions of natural ferrierites have recently been reviewed by Wise and Tschernich (American Mineralogist (1976), vol. 61, p. 60-66); they did not find lithium in natural ferrierite samples~

~186Z93 TABLE A
COMPARISON OF D SPACINGS OF TWO NATURAL AND SYNTHETIC STRONTIUM
FERRIERITES WITH THE ALLOWED LINES
FERRIERITE Ferrierite FERRIERITE, SYNTHETIC
Theoretical Kamloops Lake Agoura, Ca. STRONTIUM *
For I 2/M 2/M 2/~ B.C., Canada FERRIERITE
Where a = 19.16 b = 14.13 and c = 7.49 Relative Relative Relative hkl dA dA Intensity dA Intensity dA Intensity 11011.37 11.3 20 11.3 3 __ __ 2009.58 9.61 100 9.47 50 9.49 75 1016 98 7.00 30 {7 07 38 ~7 07 20 0116.62 6.61 20 6.59 3 6.61 55 3105.82 5.84 50 5.75 15 5.77 15 2205.69 __ __ 5.64 14 __ __ 2115.44 __ __ __ __ 5.43 5 1214.964 4.96 10- __ __ 4.96 15 -3014.860 __ __ __ __ __ __ 4004.790 4.80 10- 4.75 2 4.76 15 1304.574 4.58 10- 4.56 1 _ __ 3214.004 __ __ __ __ __ __ 0313.987 3.99 90 3.98 35 3.99 45 4203.965 __ __ 3.94 35 3.94 35 4113.880 3.88 10 __ __ 3.86 25 3303.791 3.791 20 3.78 65 3.78 50 0023.745 __ __ __ __ 3.74 10 5103 66818 3.69 50 3 66 12 ~ 3.67 30 1123.557 3.54 80 __ __ 3.555 10 0403.532 __ __ 3.54 100 3.536 90 2023.488 3.49 80 3.48 18 3.483 100 5013.411 3.42 20 __ __ 3.389 15 2403.314 3.31 20 3.31 35 3.313 20 6003.193 3.20 10 __ __ __ __ 1413.152 3.15 30 __ __ 3.142 55 3123.149 __ __ 3.14 12 __ 5213.072 3.07 30 __ __ 3.058 45 4313.064 __ __ 3.05 12 __ __ 5302.972 2.97 30 __ __ 2.960 25 4022.950 __ __ 2.9~5 11 2.938 25 6202.910 2.90 20 __ __ 2.897 35 4222.722 2.72 20 __ __ 2.715 30 0512.644 2.64 20 2.644 7 2.646 15 3502.584 2.58 30 2.582 10 2.583 10 7012.571 __ __ __ __ __ __ * Barrier and Marshall, American Mineralogist _, 484 (1965) . ~

1~)136;~93 , TABLE B
Chemical Analysis of Natural Ferrierite . . .
Locality Itomuka, Kamloops Albero ** **
Japan Lake, Bassi, Agoura, Agoura, Sonora**
Yajima, Graham Alietti Calif. Calif. Pass, et al Calif.
Oxide(1971)(1918) (1967) SiO271.21 69.13 56.8074.4075.64 66.17 A1239.84 11.44 12.718.51 9.39 10.71 10 Fe2O30 05 3.29 0.04 0.01 0.99 TiO2 - 0.10 Mno CaO - none 5.52 0.13 0.14 0.55 MgO 1.70 2.92 4.12 1.07 1.02 2.79 Na2O1.59 3.97 0.27 1.91 2.33 K2O 2.85 0.36 0.82 2.48 2.80 1.54 C2 ~ 2.84 H2O(+)4.25) 4.16~
~ 13.05 11.46 8.67 17.25 H2O(-)8.63~ 10.1 -100.12 100.87 100.79 100 100 100 Chemical Formulae of Ferrierite (Nal 32K1 57)Mgl og(Si30 gsAL5.03Feo.ol)35-99 72-01 2 (Yajima, et al.) ~ )4 g2(Si30Al6)o72(oH)2-l8H2o (Staples, 1955) Nal.5Mg2Si30.5A15.s72-1~H2 (Vaughan, 1966) Ko 51Na0 25Cao g9Mg2 98(Fel 20A17.25si27.50)o72 2 (Alietti, 1967) N 1.8Kl.4Mgo.6(si3l.6Al4 4)72 18H2O (Wise et al., 1969) . .
* From S. Yajima, et al., Mineralogical Journal, 6 343 (1971).

** W. S. Wise, et al., American Mineralogist, 54, 887 (1969).

-1~86Z93 Brief Description of the Invention We have found that the preparation of synthetic ferrierites having the X-ray diffraction patterns shown in Table C can be greatly facilitated by promoting the reaction mixtures, consisting of one or more salts of Group lA (sodium, potassium, rubidium, and cesium) and/or salts of Group II A (magnesium, barium, strontium, and calcium) of the periodic table, with silica, water, and natural or synthetic ferrierites as seeds, with lithium hydroxide.

,~, The preparation of the lithium, strontium potassium ferrierite; the lithium potassium ferrierite; and the lithium, sodium, potassium ferrierite were discussedin U.S. Patent 3,966,883. The preferred method of -~
preparing the lithium-promoted ferrierite precursor reactant mixtures is to mix the hydroxides of the salts with a source of alumina, a source of silica, water, and natural or synthetic ferrierite as seeds. Thus, the lithium magnesium ferrierite reaction mixture is prepared by mixing lithium hydroxide, magnesium hydroxide, a source of alumina, a source of silica, water, and natural or synthetic ferrierite seeds. The seeds are present in a concentration of 0.1 to 10 percent of the reaction ; mixture of a powdered or natural ferrierite, or a powdered synthetic ferrierite recovered from previous reactions.
We have further discovered that good synthetic ferrierite can be made from natural amorphous volcanic ash, both with and without seeds of natural ferrierite~
The reactions are carried out at a temperature of . , - . ., . - :, .

1~6293 90 to 325C. in enclosed vessels at a pressure of 1 to 120 atmospheres.
It is an object of the invention to prepare a highly siliceous, acid resistant zeolite for sorption, ion exchange, and catalytic uses, especially in acidic systems.
Thus, in accordance with the present teachings, a process is provided for preparing synthetic ferrierite which comprises:
a) preparing an alkaline reaction mixture which contains group I and/or group II cations, a source of alumina, a source of silica, water, powdered, natural or synthetic ferrierite seeds in a concentration of 0.1 to 10% by weight and promotional amounts of lithium cations; and b) heating the reaction mixture at a temperature of about 180 to 325 to form ferrierite.
Detailed Description of the Invention The first step of the process is the preparation of the precursor mixture. The particular mixture used, of course, depends on the desired composition of the product. The lithium, sodium, potassium, rubidium, cesium, magnesium,barium, strontium, and calcium salts are preferably added as the hydroxides. The hydroxides are preferred since it is essential that the reaction be carried out in an alkaline medium, preferably at a pH of 8 to 14.
The alumina can be added in any hydrated or amorphous form. Alpha-alumina monohydrate and bauxite give satisfactory results, in addition to commercially available alumina sols.
The silica can be added in any form that is finely divided. The silica sols give satisfactory results as do silica gel powders, such as Hi-Sil 21 ~ (a product of PPG Chemicals).
Part of the silica and all of the sodium may be added as sodium silicate if the final product is to be a lithium promoted sodium ~ .

containing ferrierite. Also, both the silica and the alumina may be supplied by pumice or tuff, natural amorphous alumino silicates. Other alkali silicates may also be used as silica sources (eg. potassium, or lithium silicates). The ratios of reactants depends, of course, on the final composition of the mixture. When the product to be recovered is a lithium-barium ferrierite the reactant mixture should have the following ratios of reactants: 0.5-1.5 Li2O: 0.25-1.5 BaO: A12O3: 6-30SiO2:
50-600H20. When the ferrierite is a lithium-potassium ferrierite ,~ :

~ , : .: ' , ~ -.

10~6~3 the ratios of reactants should be 0.5-1.5 Li2O: 0.5-1.5 K2O:
1 Al2O3: 6-3 SiO2: 50-600 H2O. Thus, the central feature of the process is the inclusion of a lithium cation in the reaction mixture together with cations of sodium, potassium, rubidium, caesium, magnesium, barium, strontium, and calcium preferably in amounts of 0.1 to 5 times the concentration of other Group I or the Group II cations.
The ferrierite seeds are usually added as a fine powder, preferably about minus 200 mesh. The seeds may be the natural ferrierite mineral, or they may be derived from any portion of a prior preparation. A sample of the natural ferrierite used as seeds from Lovelock, Nevada had the following composition in weight percent:

CaO 1.7 MgO 1.1 Fe23 1.4 TiO2 0.1 2 4.5 Na2O 0.7 A123 10.9 SiO2 79.6 ; In the preparation the components of the reaction mixture are added in the desired ratio of reactants and the reactants are transferred to a sealed pressure reaction vessel. The tem-perature is increased to about 180 to 325C. and the reaction allowed to proceed at autogenous pressure. The synthesis is normally completed in about 1 to 7 days at 300C., when the strontium is in the sole alkaline earth component. At 250C. the synthesis takes two days. However, when the alkali metal com-ponent is a mixture of strontium and lithium, lithium and sodium, .

: . . ................... . : .
. - , . . : .. ~ .. ..

strontium or sodium and lithium, the reaction is completed in a period as little as 24 hours at 225C. The reaction time is -from about 12 hours to 7 days with about 1-2 days being preferred in most cases. The temperatures of seeds syntheses are in the - range 180C. to 325C., with 200 to 250C. being preferred.
The other steps in the preparation are conventional. The -product is removed from the reaction vessel and washed free of excess reactants and dried. The washing is preferably carxied -out with deionized water at a temperature of about 20 to 80C.
Drying is immediately carried out at a temperature of about 105C.
for a period of about 1 hour.
Our invention is illustrated by the following specific but nonlimiting examples.
Example 1 A slurry of the oxide ratio 0.5 SrO:0.5 Li2O:1 A12O3:
10 SiO2: 125 H2O was prepared by blending 51 g. Sr(OH)2-8H2O, 16 g. LiOH-H2O, 149 g.~alumina sol, 445 g. silica sol, 263 g.
water and 12 g. powdered natural ferrierite. The slurry was heated in a sealed steel reaction vessel for one day at 250C.
The product was found to be good quality ferrierite.
The chemical analysis was as follows:
SrO 4.1%
Li2O 2.3%
K2O 0.2%
A123 14.5%
SiO2 78.9%

_ g _ 1~86Z93 Example 2 A slurry of the oxide ratio Li2O:A12O3:10SiO2:125 H2O was prepared by mixing 12 g. powdered natural ferrierite, 32.5 g.
LiOH-H2O, 150 g. alumina sol, 449 g. silica sol and 302 g. water.
The slurry was heated in a sealed steel reaction vessel at 250C
for one day. The product was ferrierite and had the following chemical analysis:
Li2O 5.4%
K2O 0.2 A123 13.4 SiO2 81.0%

Example 3 A slurry was prepared by the same procedure as in example 2 to achieve the oxide ratio Li2O A12O3 10 SiO2 125 H2O. The slurry was reacted in a sealed steel reaction vessel at 225C
for 1 day. The product was found to be ferrierite.
The chemical analysis was as follows:

2 5.3%
K2O 0.2%
A123 15.5%
SiO2 79-0%

Example 4 A slurr~ of the oxide ratio Li2O A12O3 10 SiO2 125 H2O was prepared using the same ingredients as in Example 2. The slurry was reacted in a sealed steel reaction vessel at 200C. A good yield of ferrierite was obtained in 5 days.

Example 5 A slurry was prepared from 17 g. -325 mesh powdered natural ferrierite, 11 g. NaOH, 34.7 g. LiOH-H2O, 209 g. alumina sol, 636 g. silica sol and 437 g. H2O. The slurry oxide ratio was .

0.75 Li2O: 0.25 Na2O: A12O3: 10 SiO2: 125 H2O. The slurry was -sealed into a steel reaction vessel, and the vessel heated at 225C for one day. The crystallized product was found to be good quality ferrierite. The chemical analysis was as follows:
Li2O 3.6%
Na2O 2.5%
K2O 0.2~

2 3 14.8%
SiO2 78.9%

Example 6 A lithium-barium ferrierite was prepared from a slurry having the following oxide ratio: 0:5Li2o:0.5 BaO:lA12O3:10SiO2:
125H20. The slurry was made by mixing 26g barium hydroxide actahydrate with a solution of 7g lithium hydroxide monohydrate in 154g water. This was added with blending to a mixture of 250g silica sol (commercially available Ludox HS-40~, 40% SiO2 and 60% H2O) and 74 g alumina sol (commercially available Q-Loid ` A-3 ~ from the Philadelphia Ouartz Co.) Finally 2.7g natural ferrierite from ~ovelock, Nevada, powdered to -325 mesh, was added as seeds; the seeds supply approximately 2.5% of the slurry alumina.
The slurry was mixed well in a Hobart~ blender, then placed in steel reaction vessels. The vessels were sealed and heated at 250C in an oven. After 48 hours the vessel was ; removed from the oven, cooled and opened. The product, a white slurry, was washed free of excess alkalinity with hot deionized water and oven dried at 105C. The dried powder was X-rayed by the powder diffraction method using copper radiation. The X-ray powder pattern showed the product to be a high purity ferrierite;
the pattern is shown in Table C.

-- 11 -- .

:' ~ ' ' -' '' ' . ' 16~86Z93 This ferrierite was calcined and chemically analyzed and found to contain the following oxides by weight percent.

Li2O 1.4 K2O 0.2 BaO 8.6 A123 11.7 SiO2 77.4 Na O 0 7 100.O

The small amount of K2O is apparently contributed by the natural ferrierite seeds which contain 4.5% K2O.

Example 7 This example demonstrates the use of Ludox HS-30 silica sol, a commercially available product, as a silica source for ferrierite synthesis. A mixture of 335g of silica sol (Ludox HS-30)~ and 74 g alumina sol (Q-Loid A-30)~ was blended in a Hobart mixer. To this were added a solution of llg lithium hydroxide ~lonohydrate in 76g water and 13g finely powdered barium hydroxide octahydrate. Lastly 2.7g natural ferrierite (from Lovelock, Nevada), powdered to -325 mesh was blended into the slurry which formed a soft paste, having the oxide ratio of 0.75Li20:0.25BaO: lA12O3:10SiO2:125H2O. The paste was trans-ferred to pressure vessels and heated at 250C. After two days (48 hours) at 250C the product recovered was shown by its X-ray powder pattern to be a well crystallized, pure ferrierite.

-- . .

8t~293 ~ :~
.,, ~ .,, ~ ~ ~ ~ o ~ o~ 1~ ~ ~ ~ ~ ~r o In ~ n I ~ o In ~ ~ co ~ oo ~g o ~ a~ ~ ~ ~ ~ ~ ~ ~ ~ r ~ o a~
s~
H
`

~1 ~1 ~1 ~ ''I
o ~ ~ N o~ I I ~ I 1--Ir) ~ u~ t~ O o 1~ ot) O 1~ ~) ~r o ~ ~ ~r a ~ aJ
C~
H
~1 O ~1 S~ ~1~
~ U~
~, ~ ~
_ ~ ~ ~ ~ r o ~ L~
~r o ~ Ln 1` ~ 1` ~ ~ oo 1~ 1` ~ n ~r ~ ~ ~ o a~
. ~ " ~ I ........ I I . I ..................

~rl ~ 'U1 ~
~1 :~a ~ ~ ~ u~ ~ ~ er co ~ I I r~ I ~ o ~ ~ I o o ~ ~9 ~ Ll~ ~ I ~ o o~ ~ I~
~ ~ O ~ ~ ~ o~
~ a) ~ ~ ~ ~; H
Q ~ ~
.~ ~ ~ In ~r o a~ u~ I~ ~o 1~ ~ ~ 00 1~ ~D Lr~ ~ ~ ~ ~ O a~ a~ t~ ~o I
U~ ~ ~ ~ ~) ~ ~r) ~) r~) ~'1 ~) ~) ~ ~ ~ N
O
U~
~ ~ 0~
a) ,~
~1 ~) ~ ~ ~ D N 1` ~ ~ ~ Hl~ ~ ~ ~ t-- ~ ~ ~ ~r O N ~ O ~ O U~ Lt ~ O tY~
m ~1 ~ ~ N ~ I ~ ~ O CO
h rl ~ H
O ~ I u~ ~ o a~ u~ I~ ~ ~r co r~ ~ ~ ~ co 1~ 1~ ~ ~ ~r ~ ~ ~ o ~ a~ a~ 1- ~ Ln :~
X '.
o a) Z ~ . ' ., ~ ~ ~ o O ~ ~ ~ ~ ~
~1 0 ~1 ~ O ~ O o ~r ~ S~ ~ ~ O O O ~ ~ O O ~ ~ O O ~ O ~ O ~ O ~ ~ ~ O ~ ~ O ~ O ~ ~ O
~; X O (d ~1 o ~ o ~1 ~ ~ ~I N O ~ `I ~1 ~ O ~ ~1 0 0 ~ ~ ~ ~) O ~ ~ 10 Ul - . ' 1~86293 A chemical analysis gave the following composition of the calcined ferrierite.
Na20 0.1 Li2O 2.5 ; 2 0.1 BaO 4.6 A123 13.0 SiO 79-7 100.0 , , Example 8 A lithium-potassium ferrierite resulted from a slurry of the ratio 0.5Li2O:0.5K2O:lA12O3:10SiO2:125H20 heated in a pres-sure vessel at 250C for one day (24 hours). The slurry was -~;
prepared by dissolving 7g lithium hydroxide monohydrate and ;
llg potassium hydroxide in 160g water. The solution of bases was mixed with 250g silica sol (Ludox HS-40)R and 74g alumina sol (Q-Loid A-30) in a HobartR mixer. Lastly, 2.7g powdered natural ferrierite, -325 mesh, was blended in as seeds. The X-ray powder pattern is essentially the same as that found for the product of Example 6. The chemical analysis of the calcined ferrierite was:
Li2o 2.0 K2O 6.0 A123 13.1 SiO2 78.9 1'00.0 The X-ray powder pattern is shown in Table C. Examples 9 thru 16 were prepared using the same procedures as described in Examples 6 thru 8. The data is presented in Table E.

: :

~ ~86Z93 o 3 ~ :

o U~ U~ o o ~ o O ~ ~ ~ ~ ~ In ~ ~ Lr~
~ ~ ~ ~ ,1 ~ ~ ~ ,/ ~ ~ U~
U~ rC

S~ ~ O o o o o t~ ,n o o 4~ :
U~ ~ O . :,~
~ . .
~ ~ o I ~j -~ ~, P 0~ e I

i~, o U~ o o o o o i ~-~ .. O I
P~,,O ~ I I ,~

~ ~ o ~1 o I ~ I I ~ ~ ....
~ O ~ O ~ O
~ z I o o I I ~ 3 a o I~
oooooooo X

~1 *
a~ o ~ ~ ~ ~r Ln ~
~ ,, ~ ~ ~ ,, ~ ~ *

., ~ *

.~

, 1~)8t;;;~93 1 N N ~ N N N N ~1 ~ O :, E~ ~3 h U U~ g g g ~ ~ ~
N N N N ~) ~ ~) N ~ $

,~
¦ N N N N N N N O

O ~D O U~ ~1 O'JJ
~ ~ ~ ~ ~ O

Q
.t" ~ o ~Ç3 Ln ~ $ ~ :

3 N ~ N ~ N ~ ~3 ~o ~ ~ ~ ~0 r ~ ~ ~ ~ t~ * *

01 ~ 01 ~ 01 N
m Q
I I ~ I r ~ r~ N ~ N ~

1~ , ~ mN ,-l ~ o ~ *
: ~ C~ O ~I N ~) ~rU~ ~*D ~ ~ ~
., ~ * ,:

.' , ~ ' - .

, ;

, a~ o ~ o o C~ o o o o a~ o o o o E~

N
~1 ~1 O a~
U~ o~ 1` ~ 00 CO
\o ' 1~ , ,' ~ ~ U~
.~
(~1 ~
~ d~
,' C.) U~ 0 1 ~ m ~ OP
rl a) ~1 ~0 ~ u~ ~ ~
8 ~ oP
-- ~o ~1 ~ o~ I o ~, ~
~ ~ dP ,. .
E~ u~ .:
.
o o~ ~ ~ ,~
.~ : ~4 o o o o o o ~ o ~1 Z N O O
1~ o\
O U~

5~ ~ oo t~ O
r~
~ r~ O r~ O O r~
oP ro ~: :

* ~C r~
. ~ o ,~
. ~ r~ r~ r~ r~ r~ r~
W
.' ~/ - 17-1~6;~93 Example 17 A reaction slurry was prepared employing the slurry oxide ratio of SrO:A12O3:10SiO2:125H2O, seeded with natural ferrierite powder takes the following times to react at various temperatures. ;

Days for Good Yield Temp. Cof Ferrierite 200 ~11 In contrast the slurries employing the oxide ratio Li2O:A12O3:10SiO2:125H2O produce a good yield of ferrierite in the following times at various temperatures.

O Days for Good Yield Example Temp. C of Ferrierite No.

Thus, the synthesis of lithium ferrierite is much more rapid than the synthesis of strontium ferrierite at 200 and 225C, making the synthesis of lithium ferrierite a more commercially useful process.

Example 18 This example demonstrates the acid stability of lithium ferrierite. A sample of lithium ferrierite was prepared by the method of Example 2. This lithium ferrierite was then boiled with 0.6M hydrochloric acid using 20g ferrierite and 200 ml 0.6M hydro-chloric acid for 1/2 hour. The product was washed free of acid, dried and calcined at 1400F for 3 hours. The nitrogen ; surface area after the above treatment was 273 m2/g as - 17a -. .
,. . ' ' . :, ~ - ' ~ : -- . ' .: - , : ~ ' ~

- 1~86293 measured on a Perkin-Elmer Shell sorptometer. Another 20g sample of lithium ferrierite was boiled in 200ml 0.6M hydrochloric acid for 1/2 hour, the acid filtered off and the ferrierite boiled another 1/2 hour in a fresh portion of 0.6M hydrochloric acid. Then the ferrierite was washed free of acid, dried and calcined at 1200F for 3 hours. The nitrogen surface area was 265 m /g.
The following examples demonstrate that ferrierite cannot be synthesized by our methods if slurries of the ratio M2O/~IO:lA12O3:8-10SiO2:100-125H20 are reacted employing powdered ferrierite as seeds without the addition of some lithium. Examples 19-24 illustrate the results obtained without the addition of lithium.
(Table F). Most of the products of these experiments are der.se phases (quartz, feldspar, and analcine), and clearly show, by reference to previous examples, that the addition of lithium to the synthesis slurry clearly has a promoting effect that directs the synthesis to ferrierite products.

i~6;~93 ~ N N

S ~3 ~ N " N ,~

p~

~ ~1~ o o o t~ 'l r~ O ~ O

~ ~oV O O O o O o ,~IJ 1~ Ul O
O ~ ~ ~ ~ ~ ~ ~

H ~ t~ t~i ~ ~ ~ ~

I
~ ~ ~ .
,~ ~ ~ 0 0 ~1 O` ~, ~ : ".

o ~r~ 0 8 ~o ~
~,, o~ o ~ ~ O ~ 4 a) ~ ~ o~
.. ~ o~ ~ , ~ X
o~ o~
o ~o,,~
Q ~ ~ V~ o o ~ S, ~1 ~ ~ ;~; O ~N 1~ 3 E4 a) . ~ I ~ ~ ~
~ ~ O~ O
~z ~I N ~I ~ ~ ~

': ' . :

Claims (10)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for preparing synthetic ferrierite which comprises:
(a) preparing an alkaline reaction mixture which contains Group I and/or Group II cations, a source of alumina, a source of silica, water, powdered, natural or synthetic ferrierite seeds in a concentration of 0.1 to 10% by weight and promotional amounts of lithium cations; and (b) heating the reaction mixture at a temperature of about 180° to 325°C to form ferrierite.

2. The process of claim 1 wherein said heating step is conducted at superatmospheric pressure.

3. The process of claim 1 wherein said reaction is conducted at autogenous pressure.

4. The process of claim 1 wherein the reaction mixture has the formula:
0.5-1.5 Li2O:0.25-1.5 BaO:Al2O3:6-30 SiO2:50-600 H2O .

5. The process of claim 1 wherein the reaction mixture has the formula:
0.5-1.5 Li2O:0.5 K2O:Al2O3:6-30 SiO2:50-600 H20 .

6. The process of claim 1 wherein the Group I
and/or Group II cations are derived from hydroxides of sodium, potassium, rubidium, caesium, magnesium, barium, strontium, and calcium.

7. In a process for preparing synthetic ferrierite wherein an alkaline reaction mixture containing Group I and/or Group II cations, a source of alumina, a source of silica, water and powdered, natural or synthetic ferrierite seeds in a concentration of 0.1 to 10 weight percent is heated to form ferrierite, the improvement comprising:
adding promotional amounts of lithium cations to the reaction mixture.

8. The process according to claim 8, wherein the Group I and Group II cations are added to the reaction mixture as the hydroxides.

9. The process according to claim 8, wherein the silica and alumina sources are silica and alumina sols.

10. The process according to claim 8, wherein the lithium cations are present in the reaction mixture in a concentration equal to 0.1 to 5 times the concentration of the Group I or Group II cations.