Inorganic Compounds with Unusual PropertiesâII - American

30 Templates in Zeolite Crystallization LOUIS D.

ROLLMANN

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Central Research Division, M o b i l Research a n d Development C o r p . , P . O . Box 1025, Princeton, N J 08540

Crystallization

of zeolites is often a

nucleation-controlled

process occurring from molecularly inhomogeneous,

aque

ous gels. The product is strongly dependent on the cation distribution in these mixtures. A methodology is developed for interpreting crystallization data and for identifying tem plate effects by added quaternary ammonium cations. These techniques are then examined, by way of example, with a series of quaternary ammonium polymers. such polymers can force crystallization

It is shown that

of large-pore zeo

lites (where small-pore structures would otherwise result), and that they can preserve the integrity of a pore system during crystallization of fault-prone zeolite structures.

^ f e o l i t e s are t h r e e - d i m e n s i o n a l , c r y s t a l l i n e n e t w o r k s o f A 1 0 a n d S i 0

4

tetrahedra, a u n i t negative charge b e i n g associated w i t h e a c h A 1 0

4

4

tetrahedron

i n the framework.

intracrystalline

cation—such

a m m o n i u m i o n — s o that

B a l a n c i n g that

charge

as s o d i u m , p o t a s s i u m ,

t h e resultant

zeolite phase

must be

or a

some

quaternary

has a n i d e a l i z e d

formula: M 0 • A1 0 2

2

3

• zSi0

2

• yH 0 2

w h e r e i n M represents a c a t i o n ( m o n o - v a l e n t i n this e x a m p l e ) .

Synthesis

of a z e o l i t e structure is c o m m o n l y effected b y h e a t i n g a n a l k a l i n e , a l u m i n o silicate " g e l , " a n d t h e structure o b t a i n e d is s t r o n g l y d e p e n d e n t o n t h e cation distribution. M o r e t h a n 130 n a t u r a l a n d synthetic zeolites are a l r e a d y d e s c r i b e d i n t h e literature ( I ) , a n d several r e v i e w s h a v e d e t a i l e d t h e r a p i d progress that

has b e e n

made

i n synthesis

efforts

(2-7).

A correlation

0-8412-0429-2/79/33-173-387$05.00/0 © 1979 American Chemical Society In Inorganic Compounds with Unusual Properties—II; King, R.; Advances in Chemistry; American Chemical Society: Washington, DC, 1979.

exists

388

INORGANIC

Table I.

COMPOUNDS

UNUSUAL

PROPERTIES

II

Comparison of Hydrocarbon and Zeolite Pore Dimensions

Pore

Diameter

Examples

12-Ring 10-Ring 8-Ring 6-Ring

6-8 5-7 4-6 2-3

M o r d e n i t e , Y , gmelinite Ferrierite, dachiardite Erionite, A S o d a l i t e , sodalite cages i n A a n d i n Y

A A A A

Hydrocarbon


WITH

Minimum

n-Hexane Cyclohexane Benzene

Dimensions

3.5 X 4.2 A 4.8 X 6.4 A 2.2 X 5.6 A

b e t w e e n the s m a l l e r cations, s o d i u m , p o t a s s i u m , a n d p o s s i b l y t e t r a m e t h y l a m m o n i u m ( T M A ) , a n d t h e p o l y h e d r a l b u i l d i n g units of several z e o l i t e structures ( 5 ) , s u g g e s t i n g that these cations t e m p l a t e o r d i r e c t c r y s t a l l i z a t i o n of specific zeolite phases.

I n g e n e r a l h o w e v e r , t h e r o l e of o r g a n i c

cations i n d i r e c t i n g c r y s t a l l i z a t i o n is a t o p i c o p e n to debate ( 5 ) . O n c e f o r m e d , m a n y z e o l i t e f r a m e w o r k s possess a p o r e system access i b l e to h y d r o c a r b o n s a n d a large, i n t e r n a l surface area w h i c h is p o t e n t i a l l y the locus of c a t a l y t i c a c t i v i t y . A l t e r n a t i v e l y , t h e a c c e s s i b i l i t y o f a z e o l i t e p o r e system to h y d r o c a r b o n s of d i f f e r i n g size c a n b e a p r o b e of t h e d i m e n s i o n s of those pores. a r i n g of S i 0

4

E a c h c h a n n e l i n a zeolite is d e f i n e d b y

a n d A 1 0 tetrahedra, a n d i t is u s e f u l to g r o u p zeolites 4

a c c o r d i n g to t h e n u m b e r of t e t r a h e d r a w h i c h constitute that r i n g , f o r e x a m p l e , 6-, 8-, 10- o r 1 2 - r i n g zeolites. the most c o m m o n catalyst c o m p o n e n t s ,

T h e last three groups c o m p r i s e a n d t h e diameters of v a r i o u s

examples of e a c h p o r e size are c o m p a r e d w i t h m i n i m u m d i m e n s i o n s of several C h y d r o c a r b o n s i n T a b l e I. 6

I n the f o l l o w i n g pages, t h e p o t e n t i a l effects of o r g a n i c cations i n d i r e c t i n g c r y s t a l l i z a t i o n of specific zeolite structures a n d t e c h n i q u e s f o r identifying such directing functions w i l l be reviewed briefly. T h e n , b y way

of e x a m p l e , t h e i n f l u e n c e of selected c a t i o n i c p o l y m e r s o n z e o l i t e

crystallization w i l l be described. Template

Effects

I n g e n e r a l , a d d i t i o n of a q u a t e r n a r y a m m o n i u m c a t i o n to a r e a c t i o n m i x t u r e c a n effect changes of three t y p e s : ( a ) a different z e o l i t e structure is o b t a i n e d ; ( b ) a z e o l i t e crystallizes w h e r e t h e r e a c t i o n m i x t u r e w o u l d o t h e r w i s e r e m a i n a m o r p h o u s i n d e f i n i t e l y ; ( c ) the same zeolite is o b t a i n e d as w i t h o u t q u a t e r n a r y , b u t i t possesses a n a l t e r e d c h e m i c a l c o m p o s i t i o n . U n l e s s c r y s t a l l i z a t i o n w a s m a r k e d l y accelerated, o n l y ( a ) a n d ( b ) w o u l d represent " t e m p l a t e effects" a t t r i b u t a b l e to t h e q u a t e r n a r y c a t i o n , a n d ( a ) is b y f a r the m o r e c o m m o n of t h e t w o effects.

In Inorganic Compounds with Unusual Properties—II; King, R.; Advances in Chemistry; American Chemical Society: Washington, DC, 1979.

30.

ROLLMANN

Templates

in Zeolite

389

Crystallization

I d e n t i f i c a t i o n of s u c h effects is m a d e d i f f i c u l t , h o w e v e r , b y the c o m p l e x i t y of a c r y s t a l l i z a t i o n e x p e r i m e n t .

C r y s t a l l i z a t i o n t y p i c a l l y occurs

f r o m a m o l e c u l a r l y i n h o m o g e n e o u s , aqueous g e l , p r e p a r e d b y c o m b i n a t i o n of a s i l i c a a n d a n a l u m i n a source together w i t h v a r y i n g amounts

of

h y d r o x i d e i o n . Since the p r o d u c t o b t a i n e d is o f t e n n u c l e a t i o n - c o n t r o l l e d , v a r i a b l e s i n a n e x p e r i m e n t c a n i n c l u d e not o n l y the s i l i c a source ( g e l , sol, s o d i u m silicate) a n d the a l u m i n a source ( s o d i u m a l u m i n a t e , a l u m i n u m s u l f a t e ) b u t also the d e t a i l e d m i x i n g a n d c r y s t a l l i z i n g p r o c e d u r e s

(tem-


peratures, a g i n g , s t i r r i n g rate, e t c . ) . A

c r y s t a l l i z a t i o n e x p e r i m e n t is best d e s c r i b e d b y m o l e ratios

r e a c t i o n m i x t u r e c o m p o n e n t s , as l i s t e d i n T a b l e I I .

of

S o d i u m silicate, f o r

e x a m p l e , is treated as a m i x t u r e of N a O H a n d S i 0 , s o d i u m a l u m i n a t e 2

as N a O H a n d A 1 0 , a n d a l u m i n u m sulfate as A 1 0 2

3

2

r e c o g n i z e d i n the c a l c u l a t i o n that A 1 0 2

3

and H S 0 . 2

4

It is

is i n c o r p o r a t e d i n t o a z e o l i t e

3

f r a m e w o r k as A 1 0 ~ , i.e., e a c h m o l e consumes t w o moles of h y d r o x i d e : 2

A1 0 2

3

+ 2 0 H " -> 2 A 1 0 - +

H 0.

2

2

M o s t s i m p l y , the ratios i n T a b l e I I Si0 :Al 0 2

2

can be d i v i d e d b y function.

ratio defines a constraint o n the o v e r a l l f r a m e w o r k c o m p o -

3

s i t i o n of the p r o d u c t . Since m a n y z e o l i t e structures c a n be s y n t h e s i z e d i n o n l y a l i m i t e d range of c o m p o s i t i o n , S i 0 : A l 0 ratio c a n also restrict 2

2

3

the n u m b e r of z e o l i t e phases p o s s i b l e f r o m a g i v e n r e a c t i o n m i x t u r e . (The

actual number w i l l

be,

c o n t i n u e to be d i s c o v e r e d . )

of course,

u n k n o w n since n e w

phases

I n most cases (the w e l l - k n o w n L i n d e z e o l i t e

4 A b e i n g a n e x c e p t i o n ) , the S i 0 : A l 0 ratio of a p r o d u c t zeolite w i l l b e 2

2

3

l o w e r t h a n that of the r e a c t i o n m i x t u r e , zeolites f r e q u e n t l y i n c o r p o r a t i n g a l l of the a l u m i n u m i n a m i x t u r e a n d l e a v i n g v a r y i n g a m o u n t s of silicate i n s o l u t i o n . I n the examples b e l o w , S i 0 : A l 0 2

2

3

ratios of the

reaction

m i x t u r e s are i n the r a n g e 10-100. F o r m a t i o n of a n o r d e r e d a l u m i n o s i l i c a t e f r a m e w o r k r e q u i r e s h y d r o l ysis a n d r e a r r a n g e m e n t of S i - O - S i ( a n d S i - O - A l ) b o n d s , the rate of that f o r m a t i o n b e i n g d e p e n d e n t o n h y d r o x i d e c o n c e n t r a t i o n (19). r e l a t e d values of H 0 : S i 0 2

Table II.

2

and O H " : S i 0

2

2

H|0:Si0 OH:Si0 +

4

molecular

Influence F r a m e w o r k composition

3

Viscosity , . molec. w t .

2

S l h c a

2

cj.p. RN-SiO K J N .HiUs

A T

define b o t h the

Reaction Mixture Composition

Mole Ratio Si0 : A1 0

2

T h e inter-

t e

| Hydroxide concentration )

Cation distribution Templating ) F r a m e w o r k A l content

)

{20,21)


390

INORGANIC

COMPOUNDS WITH UNUSUAL

PROPERTIES

II

w e i g h t d i s t r i b u t i o n of the silicate species i n a r e a c t i o n m i x t u r e a n d the rate of c h a n g e

of that d i s t r i b u t i o n . A s the O H " : S i 0

m o r e silicate r e m a i n s i n s o l u t i o n a n d l o w e r S i 0 : A l 0 2

T h u s the ratios H 0 : S i 0 2

2

2

3

ratio

increases,

p r o d u c t s result.

a n d O H " : S i 0 exert a second, i m p o r t a n t i n f l u -

2

2

ence o n the course of a c r y s t a l l i z a t i o n a n d o n the p r o d u c t o b t a i n e d . At

h i g h h y d r o x i d e levels, m o r e

dense,

more

thermodynamically

stable phases result, either as a result of the f a c i l e r e d i s t r i b u t i o n p o s s i b l e w i t h l o w m o l e c u l a r w e i g h t silicate species or as a result of

product


dissolution and recrystallization. F o r example, zeolite A ( a n eight-ring structure

capable

of s o r b i n g n o r m a l paraffins)

converts

to z e o l i t e

P

( t h e r m a l l y unstable, s o r b i n g o n l y molecules smaller t h a n H 0 ) i n d i l u t e 2

s o d i u m h y d r o x i d e a n d , i n m o r e c o n c e n t r a t e d s o l u t i o n , to the dense, sixr i n g sodalite structure ( I ) . Si0

2

I n the examples b e l o w , H 0 : S i 0 2

2

and O H ' :

h a v e values i n the ranges 10-50 a n d 0.1-2.0, r e s p e c t i v e l y . If t e m p l a t i n g is i m p o r t a n t , k e y ratios w i l l define the c a t i o n d i s t r i b u -

t i o n , N a : S i O o , K : S i 0 , R N : S i 0 , a n d so f o r t h , ratios w h i c h c a n r a n g e +

+

2

+

4

2

( i n d i v i d u a l l y ) f r o m zero to m o r e t h a n t w o . I n T a b l e I I I , examples

are

selected f r o m the literature to illustrate c a t i o n effects i n c r y s t a l l i z a t i o n experiments.

T h e Na-series examples s h o w a shift i n p r o d u c t f r o m Y to

m a z z i t e - r e l a t e d structures

(ZSM-4, Omega)

o n a d d i t i o n of o n l y s m a l l

a m o u n t s of T M A i o n . W h e n p o t a s s i u m replaces s o d i u m , the L results b u t l i m i t e d a d d i t i o n of T M A p r o d u c e s yet another

structure structural

t y p e , the offretite-type zeolites. Experiments effects, b u t they

s u c h as those w i t h T M A s t r o n g l y suggest are not of themselves

crystallization products species to nucleate

conclusive.

template

A s noted

earlier,

are o f t e n d e t e r m i n e d b y n u c l e a t i o n , the

b e i n g the

normally inhomogeneous,

product

(12).

Reaction

a n i n h o m o g e n i t y w h i c h c o u l d be

b y a d d e d q u a t e r n a r y a m m o n i u m cations.

first

mixtures

are

influenced

A d d i t i o n a l e v i d e n c e f o r tern-

p l a t i n g b y T M A i n these examples is p r o v i d e d b y e l e m e n t a l analysis. T h e offretite structure is k n o w n ( 1 3 ) .

O f f r e t i t e has a t w o - d i m e n -

s i o n a l p o r e system, large 1 2 - r i n g channels i n t e r c o n n e c t e d b y a n e i g h t - r i n g network.

It is i n the d e t a i l e d structure that e v i d e n c e

for templating

Table III. Product Dependence on Cation Distribution S i 0 : A l 0 = 16-20, H 0 : S i 0 = 14-25 1 0 0 ° C , Static 2

Zeolite Y ZSM-4 Omega L TMA-0 TMA-OfTretite

2

3

2

OH~:Si0

2

0.8 0.8 0.7 0.8 0.9 1.1

2

Na :Si0

TMA :Si0

K :Si0

0.8 0.8 0.6 0 0 0.4

0 0.04 0.14 0 0.09 0.10

0 0 0 0.8 0.8 0.7

+

2

+

2

+

2


Ref. 1 9, 10 1 1 1 11

30.

ROLLMANN

Templates

s h o u l d be sought.

in Zeolite

391

Crystallization

A u n i t c e l l of offretite contains t w o a l u m i n o s i l i c a t e

cages, a n 1 1 - h e d r o n ( c a l l e d a n e- or c a n c r i n i t e c a g e ) accessible o n l y v i a six r i n g s a n d a 1 4 - h e d r o n r e s t r i c t e d b y eight r i n g s ( a y - o r g m e l i n i t e c a g e ) . W h e n s y n t h e s i z e d , T M A - O a n d T M A - o f f r e t i t e c o n t a i n one T M A p e r u n i t c e l l that cannot b e e x c h a n g e d a n d t h a t is l o c a t e d i n e a c h of t h e g m e l i n i t e cages ( 1 , 1 3 ) . T h u s the T M A m u s t h a v e b e e n i n s i d e t h e c a g e w h e n it was f o r m e d .

( I t is i n t e r e s t i n g t h a t these T M A samples also

c o n t a i n one n o n - e x c h a n g e a b l e p o t a s s i u m i o n p e r u n i t c e l l , l o c a t e d i n s i d e Downloaded by SUNY STONY BROOK on December 17, 2014 | http://pubs.acs.org Publication Date: May 5, 1979 | doi: 10.1021/ba-1979-0173.ch030

the c a n c r i n i t e c a g e . ) O m e g a a n d m a z z i t e are p r o b a b l y i s o s t r u c t u r a l (14).

Omega then

w o u l d be a l a r g e - p o r e , 1 2 - r i n g zeolite c o n s t r u c t e d of the same 1 4 - h e d r o n or g m e l i n i t e cages f o u n d i n the offretite structure b u t w i t h t w o cages p e r u n i t c e l l . W h e n s y n t h e s i z e d , o m e g a t y p i c a l l y contains 1.6 T M A ions p e r u n i t c e l l , almost one p e r g m e l i n i t e cage examples f r o m T a b l e I I I

(J).

Thus both structural

s h o w that T M A w a s i n c o r p o r a t e d i n t o

the

z e o l i t e f r a m e w o r k as it w a s f o r m e d . It is the c o m b i n a t i o n of this f a c t w i t h the c r y s t a l l i z a t i o n d a t a i n T a b l e I I I that constitutes strong e v i d e n c e f o r t e m p l a t i n g b y T M A i n these synthesis experiments. Polymeric

Templates

U n t i l recently ( 8 ) , quaternary a m m o n i u m polymers represented an u n e x p l o r e d s p e c i a l class of o r g a n i c cations.

W i t h polymers, a growing

c r y s t a l h a d to a d m i t not just a single c a t i o n b u t a c o m p l e t e , l i n k e d c h a i n of d e f i n e d structure. F o r the present e x a m p l e , p o l y m e r s w e r e s y n t h e s i z e d b y r e a c t i o n of 1,4-diaza[2,2,2]bicyclooctane

( d a b c o ) w i t h the c o m p o u n d s B r - ( C H ) - B r , 2

n

w h e r e n = 3, 4, 5, 6, a n d 10 ( 1 5 , 1 6 , 1 7 ) . T h e c o m p o u n d s h a d a s t r u c t u r e as f o l l o w s ,

X

a n d w e r e d e s i g n a t e d b y the b r o m i d e u s e d . W i t h 1 , 4 - d i b r o m o b u t a n e , f o r e x a m p l e , the p o l y m e r w a s d e s i g n a t e d " D a b - 4 B r . " M o l e c u l a r w e i g h t s of the

polymers, estimated

f r o m the

concentration

dependence

of

the

k i n e m a t i c v i s c o s i t y i n aqueous s o l u t i o n , w e r e i n the r a n g e 2000-15,000. T h e D a b - 4 B r , f o r e x a m p l e , h a d a n average m o l e c u l a r w e i g h t of a b o u t 10,000

(8).

A p o l y m e r must, b y its v e r y nature, b e a c c o m m o d a t e d i n t h e pores r a t h e r t h a n i n the s m a l l cages of a c r y s t a l l i z i n g z e o l i t e structure. I n the


392

INORGANIC

COMPOUNDS WITH UNUSUAL

PROPERTIES

II

f o l l o w i n g results t w o zeolites w i l l be i m p o r t a n t , g m e l i n i t e a n d m o r d e n i t e , b o t h l a r g e - p o r e , 12-ring structures as n o t e d i n T a b l e I. G m e l i n i t e s , h o w ever, b o t h n a t u r a l a n d synthetic, e x h i b i t the sorptive p r o p e r t i e s of s m a l l r a t h e r t h a n large-pore zeolites.

S u c h b e h a v i o r is a t t r i b u t e d to c h a b a z i t e

s t a c k i n g faults, faults that f o r m i n a p l a n e p e r p e n d i c u l a r to a n d b l o c k i n g access to the large g m e l i n i t e channels a n d that c a n be o b s e r v e d b y x-ray d i f f r a c t i o n . If a fault-free g m e l i n i t e c o u l d be p r e p a r e d , t h e n , s u b s t a n t i a l changes i n s o r p t i v e p r o p e r t i e s s h o u l d result f r o m those f o u n d w i t h c u r r e n t


samples. M o r d e n i t e is a s e c o n d 1 2 - r i n g z e o l i t e w h o s e s o r p t i v e p r o p e r t i e s d o not a l w a y s c o r r e s p o n d to expectations b a s e d o n structure. T w o synthetic types of m o r d e n i t e h a v e b e e n r e p o r t e d b y S a n d , " l a r g e - p o r t " a n d " s m a l l port" mordenite (18).

T h e former, synthesized from only a narrow range

of r e a c t i o n m i x t u r e c o m p o s i t i o n s , exhibits the s o r p t i v e p r o p e r t i e s e x p e c t e d of a 1 2 - r i n g c h a n n e l ( h a v i n g a d i a m e t e r of 6-8 A ) . T h e latter has a n a d s o r p t i o n d i a m e t e r of o n l y a b o u t 4 A . It is i n d i s t i n g u i s h a b l e f r o m largep o r t m o r d e n i t e b y x-ray d i f f r a c t i o n a n d m a y co-exist w i t h dense

struc-

tures s u c h as analcite. T w o series of experiments w e r e c o n d u c t e d to explore the effects of c a t i o n i c p o l y m e r s i n c r y s t a l l i z i n g m i x t u r e s ; one at 9 0 ° C a n d the at 1 8 0 ° C . base

case of

Na :Si0 +

ensure

2

other

T h e c o m p o s i t i o n of the r e a c t i o n m i x t u r e s w a s v a r i e d a b o u t a S i 0 : A l 0 = 30, 2

2

3

H O:SiO 2

2

= 20,

OH:Si0

2

=

1.2,

and

= 1.2. T i m e w a s v a r i e d i n the r a n g e of 3 - 1 3 days ( o r m o r e ) to

that

the

results

obtained

were

not

artifacts

of

a

sequential

c r y s t a l l i z a t i o n process. I n the absence of p o l y e l e c t r o l y t e , the l o w - t e m p e r a t u r e

experiments

p r o d u c e d the large-pore z e o l i t e Y , c o n t a m i n a t e d w i t h v a r y i n g a m o u n t s of the t h e r m a l l y u n s t a b l e phase P .

T h a t t w o zeolites, Y a n d P , w e r e

p r o d u c e d ,was e x p e c t e d since it is w e l l k n o w n that b o t h c a n f o r m i n t h e same o v e r a l l c o m p o s i t i o n field, t h e i r respective a m o u n t s d e p e n d i n g o n r e l a t i v e n u c l e a t i o n a n d g r o w t h rates ( 1 2 ) .

T h e significant p o i n t is that

o n l y these t w o zeolites w e r e o b s e r v e d i n these p o l y m e r - f r e e , l o w - t e m p e r a t u r e experiments. A s s h o w n i n T a b l e I V , e v e n v e r y s m a l l amounts of the D a b - 4 p o l y m e r ( R N : S i 0 = 0.01) 4

+

2

G m e l i n i t e w a s p r o d u c e d ( a l t h o u g h x-ray d i f f r a c t i o n s h o w e d i t to faulted by chabazite).

Br

effected a c o m p l e t e c h a n g e i n t h e p r o d u c t .

A s the a m o u n t of p o l y m e r w a s i n c r e a s e d ,

be the

p r o d u c t s h i f t e d to p u r e g m e l i n i t e . E v e n t u a l l y c r y s t a l l i z a t i o n w a s i n h i b i t e d b y the p o l y m e r , p r o b a b l y because the f o r m i n g z e o l i t e c o u l d a c c o m m o d a t e o r g a n i c cations o n l y i n a m o u n t s c o r r e s p o n d i n g to its p o r e v o l u m e . If t e m p l a t i n g is i n v o l v e d , one w o u l d expect the effectiveness of a p o l y e l e c t r o l y t e to d e p e n d o n its structure.

T h e data i n Table V

were

o b t a i n e d at the c o m p o s i t i o n o p t i m u m f o r D a b - 4 B r i n the synthesis of


30.

ROLLMANN

Templates

Table IV.

in Zeolite

Crystallization Results at Low Static, 90°C

Polymer


None Dab-4 Dab-4 Dab-4 Dab-4

N :Si0 +

Temperature Product

2

0 0.01 0.14 0.23 0.43

Br Br Br Br

393

Crystallization

Y(+P) G m e l i n i t e (faulted) G m e l i n i t e (faulted) Pure gmelinite Amorphous

p u r e g m e l i n i t e , a n d three p o l y m e r s p r o d u c e d g m e l i n i t e , D a b - 4 , -5, a n d -6.

N e i t h e r D a b - 3 or -10 nor the d i p r o p y l a n d d i b u t y l m o n o m e r s

were

effective. Product

analysis

f u n c t i o n of the cyclohexane 1.0%

provides supporting evidence

polymer.

( 2 5 ° C , p:p

0

The

pure

f o r the

g m e l i n i t e samples

directing

sorbed

7.3%

after c a l c i n a t i o n , c o m p a r e d w i t h o n l y

= 0.67)

for a natural, faulted sample.

The

C : N r a t i o i n the

gmelinite

samples a v e r a g e d 5.4, c o m p a r e d w i t h 5.1 i n the D a b - 4 B r u s e d . T h e structure of g m e l i n i t e is k n o w n a n d it is i n s t r u c t i v e to c o m p a r e its u n i t c e l l d i m e n s i o n s w i t h the l e n g t h of a p o l y m e r r e p e a t i n g u n i t . u n i t c e l l of g m e l i n i t e contains i n the d i r e c t i o n of that p o r e .

one l a r g e p o r e w h i c h is 10.0

F r o m C o u r t a u l d models one can

A

A

long

estimate

the l e n g t h of a p o l y m e r r e p e a t i n g u n i t as f o l l o w s : Dab-3 -4 -5 -6 -10

7.5 A 8.7 9.9 11.0 14.5

O n l y those p o l y m e r s that h a d r e p e a t i n g units 9-11 A l o n g w e r e effective, a n excellent c o r r e l a t i o n w i t h the d i m e n s i o n s of the g m e l i n i t e u n i t c e l l . F u r t h e r m o r e , one t h e n w o u l d expect t w o q u a t e r n a r y n i t r o g e n atoms p e r u n i t c e l l . E l e m e n t a l analysis a v e r a g e d 2.3.

Table V .

Effect of Polymer Structure on Crystallization at Product

Polymer Dab-3 Br Dab-4 B r Dab-5 Br Dab-6 Br Dab-10 B r Dab-Pr Dab-Bu 2

2

P Pure gmelinite G m e l i n i t e (faulted) G m e l i n i t e (faulted) Y + P Y + P Y + P


90°C

394

INORGANIC COMPOUNDS W I T H

Table V I .

UNUSUAL PROPERTIES

II

Crystallization Results at H i g h Temperature Static, 1 8 0 ° C

Polymer None Dab-4 B r Dab-4 B r Dab-4 B r

Product

N :Si0 +

2

Analcite Analcite Analcite + Mordenite Pure mordenite

0 0.11 0.23 0.43


I n T a b l e V I a r e d a t a s h o w i n g that these results a r e n o t a n a r t i f a c t specific t o t h e g m e l i n i t e s t r u c t u r e .

A t h i g h temperature the reaction

m i x t u r e o r i g i n a l l y p r o d u c i n g Y y i e l d e d a dense phase, a n a l c i t e ; a d d i t i o n of p o l y m e r s h i f t e d t h e p r o d u c t to a l a r g e - p o r e structure, m o r d e n i t e . T h a t this m o r d e n i t e w a s o f t h e " l a r g e - p o r t " v a r i e t y w a s s h o w n b y cyclohexane sorption ( 6 . 3 % , 2 5 ° C , p : p = 0.67). Correlation was again o

f o u n d between the unit cell dimension along a mordenite pore (7.5 A ) and

t h e l e n g t h o f a p o l y m e r r e p e a t i n g u n i t ( 8 . 7 A ) . B a s e d o n these

d i m e n s i o n s o n e w o u l d expect s o m e w h a t less t h a n t w o n i t r o g e n atoms p e r u n i t c e l l a n d analysis shows 1.7, i n excellent agreement. and

Thus a templating

d i r e c t i n g f u n c t i o n o f these p o l y m e r s c a n b e s h o w n f o r a r a n g e o f

t e m p e r a t u r e s , c o m p o s i t i o n s , a n d resultant structures. Acknowledgment A

s u r v e y p a p e r i n t h e area o f z e o l i t e c r y s t a l l i z a t i o n c a n o n l y b e

written f r o m the legacy a n d the accomplishments of a large n u m b e r of t a l e n t e d researchers.

I a m particularly indebted to G . T . Kerr, R . H .

Daniels, E . W . Valyocsik, a n d D . H . Olson, w h o have directly contributed to these results, a n d to t h e m a n y p e o p l e i n o u r P a u l s b o r o l a b o r a t o r y w h o s e w o r k has p r o v i d e d t h e basis f o r s u m m a r y . Literature Cited 1. Breck, D. W., "Zeolite Molecular Sieves," John Wiley and Sons, New York, 1974. 2. Barrer, R. M., "Molecular Sieves," p. 39, Society of the Chemical Industry, London, 1968. 3. Zhdanov, S. P., ADV. C H E M . SER. (1971) 101, 20. 4. Senderov, E. E., Khitarov, N. E., "Zeolites, Their Synthesis and Conditions of Formation in Nature," Nauka Publishing House, Moscow, 1970. 5. Flanigen, E. M., ADV. C H E M . SER. (1973) 121, 119. 6. Schwochow, F., Puppe, L., Angew. Chem., Int. Ed. Engl. (1975) 14, 620. 7. Robson, H . E., Prepr., Div. Pet. Chem., Am. Chem. Soc. (1977) 22(2), 500. 8. Daniels, R. H., Kerr, G. T., Rollmann, L. D., J. Am. Chem. Soc. (1978) 100, 3097. 9. Ciric, J., French Patent 1,502,289 (1966). 10. Plank, C. J., Rosinski, E. J., Rubin, M. K., British Patent 1,117,568 (1968).


30.

11. 12. 13. 14. 15.


16. 17. 18. 19. 20. 21.

ROLLMANN

Templates

in Zeolite

Crystallization

395

Jenkins, E. E., U.S. Patent 3,578,398 (1971). Kerr, G. T., J .Phys. Chem. (1968) 72, 1385. Gard, J. A., Tait, J. M., Acta Crystallogr. (1972) B28, 825. Rinaldi, R., Pluth, J. J., Smith, J. V., Acta Crystallogr. (1975) B31, 1603. Rembaum, A., Baumgartner, W., Eisenberg, A., J. Polym. Sci. B (1968) 6, 159. Noguchi, H., Rembaum, A., J. Polym. Sci. B (1969) 7, 383. Salamone, J. C., Snider, B., J. Polym. Sci. A-1 (1970) 8, 3495. Sand, L. B., "Molecular Sieves," p. 71, Society of the Chemical Industry, London, 1968. Kerr, G. T., J. Phys. Chem. (1966) 70, 1047. Barrer, R.M.,Denny, P. J., J. Chem. Soc. (1961) 971. Kerr, G. T., Inorg. Chem. (1966) 5, 1537.

RECEIVED February 2, 1978.


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