Note: Descriptions are shown in the official language in which they were submitted.
1~L3~LZV~
"ALU~ MODIFIED SILICA ~ USES I~S A CATl~LYST"
Thls invention rela-tes to a crystalline silica mo-
dified with ~l~ninurn, ~Iany materials~ basccl on silica
and alumina, are known, a few of natural occurrence and
5 others man made,
~ lore particularly are known9 amon~r such materials~
those ~rhich are callecl zeoli.tes~ which have absorbent,
molecular sieve and catalyti.c properties.
Such material have a content of alumina ~rhich va-
ries 1rithin a wide ran~e of ratios relative to silic~,the ma~imum silica/alumina ratio being 100:1, but this
ratio is ~enerally much smaller ancl is ~referably in the
neighborhood of 2.
These materials~ which contain aluminum in tetrahe-
dral coordination as replacen1ent for silicon must poss~ss,
in order that they may reach elec.tric neutrality, cations
capable of balancing the charges clue to the presence of
the tetrahedrally coordinated aluminum ~toms.
; The protonic acidity of such zeolites can be attri~
b~lted to the hydrogen atoms ~rhich have ~een introcluced
to e~change such cation.s. On the other hand, crystallino
silicas~ due to their intri.nsi.c nature9 do not possess
protonic charges so that they cannot display any acidic
character which is not that inherent in the silicic acid,
A number of crystalline silicas are known7 in fact,
from cristobalitc to tridymite "~eatito, and many others,
1rhich are prepared acco~din~ to ~rocedures which ha~e
been 1~idely disclosed by thc scientific litcrature~
For ex~nplc Heidcmann; in ~oitr, Min, ~etro~, 10,
30 2~2 (1~6~) obtai.ns, by r~actin~ a1l amorpho-ls silica~.th
.
$~
~3~Z~
0.55~, of I~OI-I at 1S0C ~or two days and a half, a c~ystal-
lino silica, called silica ~, wllich llas, ho~ever~ a spc-
ci.fic sur~ace area of about 10 m~/~ (sq~tare metre pe-r
~rarn) and has a poor stabi:Lity since it becomes altered
to cristobalite ~ thin five days and is subse~uently
chan~red into q-lartz.
~ Iore reccnt:Ly, Flani~en et al, Nature, 2~, 51~
(197S) have obtained a crystalli.ne silica, tha silicali-
te~ ~1hich has a high specific snrface area and which, due
to its hydrophobic proper-ties, they have sug~estcd its
use for the purification of .~aters ~hich had bcon poll~lt-
ed by organic s~bstances.
~ n object o~ the present inven-tion is to modi~y thc
nat1lre of a crystalline silica by the a~oncy of aluminum,
~hile leavill~ tho stability of s~lch a silica unaltered
30 as to permit its use as a catalyst~ or for the l~repa-
ration of catalysts~
; ~s a matter of fact, it has surprisingly been found
that it is possible to obtain ~aterials having a very
high silica-to~alumina ratio but l~hich cannot be zeoli-
tes since the minimum amounts of aluminull1 contained the-
rein cannot justi~y a structure Or the type o~ a crystal-
line silicoaluminateO
On the othcr hand, these novel materials distin~lish
ovor the crystalline silicas sharply in that the intro-
d~lction of tiny amounts of al~unimuD induces a wide varia
tion of aciclity.
Such materials~ in point of ract, pOSSQSS a proto-
nic acidity equal to, or ~reater than, that of the p~o-
tonic forms o~ the zeolites themselves while ~a-intaiIling
th~ very ni~h str~ctural stability prope. of a crystal-
line silica, con'crary to ~hat is experi.enccd for the pro-
-tonic forms of the zcolites ~,X~Y (thc only oxception
bcin, that o~ the mordenita family) ~1hich are rather la- -
bilo as they ten~ to be rcadjly converted into thc stab-
ler silica al~lminas~
Thc s~ ica al~lm:inas, as such, possess a~l ~ciclit)r
~L:3L3~L~o~
which is somewhat lower: -for example, a commercial silica
alumina containing the 25~ by wt of alumina has a concentration,
in terms of H~ milliequivalents (meq) per gram of catalyst in
the order of magnitude of 1. 10
It has been surprisingly found, furthermore, that by
properly metering the quantity of aluminum in the materials,
it is possible to adjust the acidity thereof so as to adapt it
particularly to the range required by the kind of reaction for
; which the material concerned is to be employed.
An object of the present invention is to provide a
silica, modified by the introduction of aluminum atoms in such
a way as to display those properties of acidity and ca~talytic
. activity which is the most suitable for certain reactions.
Another object of the present invention is to sug-
gest a procedure which lends itself well to the preparation of
materials of the kind referred to above.
The silica modified by the introduction of aluminum
~- atoms has the following general formula:
1 Si.(0.0012 - 0~0050) Al.Oy
wherein y is from 2.0018 to 2.0075.
Consistently with the calcination (firing) tempera-
ture, greater or smaller amounts of crystallization water can
be present.
In order that the aluminum-modified silica of the
present invention may be obtained, it is possible to adopt,
with advantage, the preparation procedure to be outlined here-
under.
A derivative of silicon and a derivative of aluminum
are caused to react in an aqueous, alcoholic or hydroalcoholic
solution with a substance having a clathrating or archivolt
eect, selected from the group consisting of tertiary amines,
aminoalcohols, aminoacids and polyalcohols, possibly adding
- 3 -
,l ,, I
)6
one or more mineralizing agents to encourage crystallization,
and possibly also an inorganic base, allowing the resultant
mixture to crystallize in an enclosure for a period of time of
from a few hours to several days at a temperature of from 100C
to 220C, preferably at a temperature from 150C to 200C for
a week, allowing to cool, filtering and drying the crystalli-
zate,firing in air at a temperature comprised between 300C and
700C, preferably at 550C, for a time between 2 hours to 24
hours, then washing the calcined product with distilled water
and firing once again in air at a temperature comprised between
300C and 700C for a time of from 2 hours to 24 hours.
The derivatives of silicon can be selected from among
a silica-gel (no matter how obtained) or a tetraalkyl ortho-
silicate, such as tetraethyl orthosilicate and tetramethyl
orthosilicate.
The derivatives of aluminum can preferably be selec-
ted from among the salts of aluminum, such as nitrates and
acetates.
The substances having a archivolt action have the
function of originating a crystalline structure with pores
having a determined size and thus are composed by adé~uately
large molecules.
The mineralizing agents can be selected from among
the group consisting of LiOH, NaOH, KOH, Ca(OH)2, KBr, NaBr,
NaI, CaI2 and CaBr2O
The added inorganic base can be selected from among
the group consisting of NaOH, KOH and Ca(OH~2.
As regards the amount to be used of the inorganic
base and/or of clathrating substance, they are generally
2~3~
lower than the stoichlometrlc amount relative to silica and
are preferably from 0.05 and 0.50 mol per mol of silica.
The product thus obtained are characterized by an
acidity of the protonic type which can be monitored by varying
the Sl-replacing cation which is introduced. For a pure silica
there is a number of milliequivalents of hydrogen ions per
gram of sample, of 1 . lO 3, but this acidity can be increased
by the introduction of aluminum until reaching a number of
~; milliequivalents of hydrogen ions per gram of sample of about
10 1 10~1 ''
The materials according to the present invention
are characterized by`a well defined crystalline structure as
can be seen in the X-ray diffraction spectra reported on Figures
1 and 2 of the accompanying drawings and possess a high specific
surface area which is over 150 m2/g and is generally comprised
between 300 m2/g and 500 m2/g.
The presence of aluminum, which so deeply modifies
the acidity of the silica, gives rise to the formation of
crystalline materials the spectra of wh~ich can either be consider-
ably resembling those reported by the literature for the crystal-
line silica called silicalite (Nature, ~71~ 512 (1978), or,
conversely, remarkably different therefrom.
The silica which has been aluminum-modified according
to the present invention can be employed for catalytic or
absorption uses, either a]one or dispersed on a more or less
inert supporting body, with a high and a 1QW specific surface
area and porosity.
The supporting body has the task of improving the
physical and mechanical stability and possibly also the catalytic
properties of the material concerned. The procedure which can
be used for obtaining a supported material can be selected from
among those known in the art and to the skilled artisans.
The quantity of supporting bGdy can be comprised
~ 5
zo~
between 1p' and 90,~ but the range ~rom 5~0 to 60~' is pre-
~erred.
Among the preferred supporting bodies, there can be
cited clays~ silica, aluminag diatomaoeous earth~ sili-
5 ca-alumina ancl many others.
The aluminum-modifi~d silica accordin~ to this in-
vention can profitably be employed as a catalyst for a
large number of reactions among which there can bc indi-
cat~d the alkylatlon of benzene, more particularly the
alkylation of benze~e with ethylene~ the alkylation of
benzene with ethanol.
Other ~ossible uses are:
1. Alkylation of toluene with methanol to produce .~ylene,
prevailingly para~Yylene.
2. Disproportionation of toluene to produce para,Yylene
predominantly.
3. Conve~sion of dimethyl ether and/or methanol or other
lower alcohols into hydrocarbons (olefines and aroma-
tics),
l~ Craclcing and hydrocrackin~. -
5. Isomeri~ation of nor,paraffins and naphthenes.
6. Pol~erization of compo~mds which contain olefine or
acetylene bonds. - -
7 r R~forming
8. Isomerization of ~olyalkyl substituted aromatics, such
as o.sylene,
9. Disproportionation of aromatics~ especially toluene.
10.Conrersion o~ aliphatic carbonyl compounds into at
least partially aromatic hydrocarbons~
11.Separation of ethylben~ene from other C~ aromatic hy-
drocarbons.
12.~Iydrogenation and dehydrogcnation of hydrocarbons.
13.Methanation~ ~
A few e~amplQs will now be given which ha~e the pur-
~ose of better illustratin~ the invention without limi-
tation~
E,~L~ 1
~3~Z~36
: This example is illustrative o~ the preparation of
the porous crystalline silica T~S-22 in the crystalline
lattice of ~fhich there has been introduced alumi~m as
silicon-ropl~cin~ element.
A Pyrex~lass vessel ~fhich is constantly l~ept in a
nitrogen atmosphere, is charged with ~0 g of tetraethyl
orthosilicate (T~OS) lfhich are ncated ~ith stirrin.~ -to a
temperature of 80C. There is added then a solution1 in
80 mls of dlst. waterJ of 20 ~ of tetrapropylammonium
hydro~ide (obtained from tetraprop~rlammonium and moisten-
ed silver o lde so as to have a product free of inorga-
nic all~aline bases) and stirrinO is continued at 80C un-
til the mi~ture is homo~eneous and clear, that ~fhich takes
about one hour.
- There are added subsequently ~0 mg (milligrams) of
~l(N03)3.9H20 dissolved in 50 mls of abs. ethanol.
A coAmpact gel i5 formed almost immediately, and
dist. ~fater is ad.ded theroto to make up to an overall vo-
lume of ~00 mls~ stirring being activatcd if necossary
and tho mi~ture is brou~lt to a boil so as -to complete
the hydrolysis and to clrive off all -th~3 c-thanol~ i.e.
the one ~Yhich has been addecl and the one set free by the
hydrolysis.
The time taken by these steps is from 2 to 3 hours-
: 25 and the gel is converted, slo~ and gradually into a
~hite po~lder~ ~Jhich is the pr-3cursor of thQ modified
crystalline silica.
~he mi~turc is made up to 150 mls with d.-i.st. water alld
~ then the Pyre~-glass vessel is introduced in an autocla
; 30 ve and it is maintainecl therein at tho temperature of
: 155~C durin~ 7 days. Upon coolin~, the solid which has
been formed is centrifugecl at a speed of 10,000 r-pm for
15 mins.~ is reslurried in dist ~fater and centrifuO~ed
once morc and this washin~ s-tcp i5 repeatecl four timcs~
The procluct is ovon dried at 12QC ancl it is seen that
it is ~-ray crystallinc.
The chomical anal.ysis of the sample, driecl at 120C,
~3~6
gives the composition:
~0 ~t SiO2 83.0
S wt ~l203 0.2
/o~-t Na20 0.18
; 5 ,' wt Lrzo 0002
; Loss on firin~ at 1100C = 16~6f~J
The molar ratio of SiO2 to ~l203 is 70~.
The allali metals which are prescnt come from the
reactants and from the ~lass, since they havG not deli-
berately bsen added,
In order that the all~aline impurities which are pre-
sent may com~letf-~ly be removed from the compound, ths
latter can be fired for 16 hours at 550C in an air stream
and subscqucntely it can repcatfdly bee l~ashecl with boil-
in~ dist. watfr containing, clissolved thcrein 7 arnmoniumacctate and fircd again at 550C for 6 hours.
The s~ecific s~lrface area, as dctermined ~ith the
BET method is 1~ m2/g~
The concentration of protonic milliequivalen-ts per
gram of sa~ple is 1.5 4 1 0
E~MPJ.E 2
This e~.ampl~ is illustrative of the prepar~tion of
the porous crystalline silica T~S-O, in the crystallinc
lattice of lJhich traces o~ aluminum have been introduced
as replacemfnts for thf~ silicon~
A Pyre~ lass fla5k equipped ~rith reflux condenser
and maintained in a nitrogen atmosphere~ is charged with
40 ~ of tctraethyl orthosilicate ~T~OS) and 12~ mls of a
20f/o aq~eous solution of tetrapropylammonium hydro~ide
(conc, by ~rt~ and tho mixture is heated to the boil.
Thc fina~ result is a clear, colorlcss solution
which remains limpid cven after a long refluxing,
At this stagr, there are addcd 30 m~ (milli~rams)
of Al(~03)3~9~12o ancl the llquor bc~comes opalrsccnt and,
3~ by continuinO thc administration of heat, a whitc po~rrlor
is separatod thcrcfrom~
~olling is continuc~fl durin~ 6 da~rs, ~ihcreaftor thc
.
)6
mixture is allo~red to cool, the solid lS collected on a
filter and ~ashed ~rith dist, water and dricd at 100C.
The prodttct, drled at 100C, is X-ray crystallinc,
It is fired for 16 hours at 550C in ~n air stream and
is subsequently repeatedly ~Yashed with boiling dist. ~ra-
ter ~rhich contains, dissolved therein, ammonium acetate,
~hereafter the solid is fired at 550C once more for 6
hours~
The chemical analysis on the procluet thus obtained
~ives the compositioll reported hereunder:
wt of SiO2 96.2
wt o~ ~l203 002
o~ wt of ~2~2 0.02
1~cight loss on ~irin~ at 1100C - 3,58~
The molar ratio of SiO2 to ~l203 is 816-
The traces of alkali metals which are present come
from the reactants and the glass si~lco they have not de-
liberately been aclded. The 5pQCifiC surfac~ area~ as de-
terrnined with the BET method is ~20 m /g~
The concentration in protonic milliequi~alents per
gram of sample is 1.9 . 10 1.
, X~MFL'~
This e~amp~e is illustrative of the preparation of
a porous cry~talline silica, called TP~S-23, in the cry-
sta1line lattice of which alurninum has been introducecl
as a r~placernent for silicon and in the preparation of
sueh silica an organic base has been used, tetraethylam-
monium hydro~lde, clifferent from thc base used for the
~xamples 1 and 2 hereof.
The procedure is as in ~xarnple 1, by reactin~ 80 ~
of tetraethyl orthosilicate~ 68 mls o~ ~ 25,' (by ~rt) a-
queous solution of tetraethylammonium hydro~ide1 80 mO~
of ~ T03)3,9H~0 dissolved in 50 ~S of abs. ethanol a~d
2 g of ~aOH pellets dissolvcd in 10 mls of dist~ ~ater~
this mixt~lrc b~in~ mantained at the te~peraturc of 155C
~or 18 days.
The pro~llct, wherl dricd at 120C~ is ,~-ray crys-tal-
-- lo --
line, The conccntration of pro-tonic milliequivalen-ts per
gram o~ s~mple (~ircd at 550C) is 1,1 ~ 10 6.
The cho~ical analysis, made on a thoroughly washcd
sample which has then been fired at 550C, gives -the com
position:
by wt SiO2 96~3
p by wt ~l203 0~2
c/~ by wt Na20 -3
~Jeight loss on firing at 1100C -- 3~7~
The molar ratio SiO2 to ~1203 is 81~.
The specific surface area, as determined with the
BET method, is 1~70 m2/g.
The cGnccntration o~ protonic milLiequiva1en-ts pcr
gram of sample is ~,3 ~ 10 3.
This example is illus*rative of the preparation of
a porous crystaIline silica9 initiallcd TRS-19, in the
cryst~lline lattice of which aluminum has be~n introduc-
ed as a replacement for silicon: in the preparatio3l of
this silica, an or~anic base has been used, which is dif-
ferent from those used in the ~revious e~amples~ and is
tetrabutylammonium hydro-Yide,
The procedure is the same as in E~ample 1, by react-
ing ~0 g of tetraethyl orthosilicate (T~OS), a solution
25 of 100 mg of Al~03~3,~l-I2o in 50 mls of abs~ ethanol, a
solution o~ 29 g o~ tetrabutylammonium hydro~id~ (ob*ain-
ed from tetrabutylammonium bromide and moistened silver
o~idc) in 1~0 mls of dist. water and 2 ~ of MaOtI dissolv-
ed in 20 mls of dist~ water.
This mi~tu~e is placed in an auto~la~e and h~ld for
16 d~ys at the tem~erature of 155C.
The product, dried at 1~0C i~ ~_r~r crystallinc.
Thc co~centration of protonic milliequivaleIlts per
gram of sample (fired at5~0C) is 4.5 . 10 ~0
The chemiea1 analysis on a thorou~hly washed sample
gives the following composition:
p by wt SiO~ ~6.0
.3~
/0 by wt ~l203 0.3
7' by wt Na~0 0,03
Wei~ht loss on firin~ at 1100~ = 3.67'
The molar ratio SiO2 to ~l203 is 5~3.
The speci~ c sur~ace area, as measured with the B~T
method is 3S0 M2/g.
'~he concentration of milliec~uivalcnts ~I~ per gram
of sample is 2~5 . 10 1,
~ Fi~lrc 1 of the accompanying drawings shows the ~-
ray diflraction spectrum of the product of this e-ca~nnle.
~L~ 5
This cxample is illustrative of the preparation of
a porous crystalline silica, initjalled TRS-20, in -the
crystalline lattice of which aluminum has been introduced
as the modifyin~ element in renlacement for silicon. The
preparation of this silica has bee~carried out without
any inorganic all~aline basc being present: the only alka-
line cations might con1e from the traces of impurities
which aro present in the usecl reactants.
By adopting the same procedure as in ~cample 1,
thcre are reacted 40 g of tetraethyl orthosilicate~ a so-
lution o~ 100 m~ of ~ 03)3.9H20 in 50 mls of abs. e-
thanol3 50 mls of a 407' (by wt) aqueous solution of te~
trapropylamrnonium hydroxicle (obtained from tetra~ropyl-
ammonium bromicle and moistened sil~er o~cide~ in orcler -to
obtain a product free of alI~aline inorganic bases and
the mi~t~trs is maintainéd at 155~C for 10 days,
The X-ray analysis indicatcs the crystallino charac-
ter o* the sample dried at 120C~
For the use as a cataly~t, the product is fired at
550C in air -for 16 hours and then repeatedly washecl
with boili~c~st. ~ater contain:in~ disso~vecl therein am-
monium acetate and lastly the solid is fired once a~ain
at 550C for 6 hours.
'~he procluct thus obtained has the following c~lemical
analytical composition:
~ by wt SiO2 96 0
- 12 -
~O by Itt ~l203 o,3
c~ by wt Na20 0.01
Weight loss on firing at 1100C = 3.59~,~
The molar ~tio Si2 to ~l203 is 51~
The s~ecific surface area as determined with the BET
methocl is as high as 500 m2/g.
The concentration of H~ions per gram of sample is
4.7 . 10 1meq.
PXA~IPL~ 6
0 This e~ample is illustrative of the prepRration of
the porous crystalline silica TRS-5~7 in the crystalline
lattice of ~hich alumin~un has been introduced as the rno-
difier. In the preparation of the silica in questi~n,
triet~anolamine has been used~
lS There are reacted ~0 g of tetraethyl orthosilicate,
80 mg of ~l~N03)3.9H20 dissolved in 50 mls o~ abs. etha~
nol~ a solution of 27 g of triethanolamine in 50 mls of
distS water~ -the procedure being as disclosed in ~arnple
1 hereo~. -
There are now a~decl 7 g of sodium hydro~ide and the
Pyrex-glass ~essel is laced in an autocla~e and maintan-
ed at the tcm era-ture of 194C ~or 7 days.
It is ascertained that the product dried at 120C
is X-ray c~ystallinec
The X-ray ~iffraction spectrum ~ this product is de-
pieted in ~igure 2 of the accornpanyin~ drawings.
~he chemieal analysis on the sampleg fired at 550C~
gi~es the following results:
,~ ~y wt SiOz ~602
30 fjo by wt ~l203 0~2
7b ~y wt Ma20 0.05
Weight loss on firing at 1100C - 3 i55~ob
The molarratio SiO2 to ~1~03 is ~l6.
The speci~ic surface area is, when measured ~th the
B~T methodg 3~ m /g~ and the concentration of ~I~meq ?er
gram o~ sample is 1~5 . 10 ~ -
~) .
- 13 -
This e~ample is illustrative of the lacl; of dehydrat-
i~ catalytic properties of the modified crystalline 5i-
lica TRS-~2 preparcd acc~ling to ~:am,)le 1 here~of but
containing sodium cations 3 SO that the concentration of
protonic.milliequi~alents per gram of sample is as low
a s 4 .1 . 1 0
The for~ation of dimethyl ether from methanol has
been selected as the e,~emplary dehydration reaction,
- An electrically heated tubular reactor having the
inside diameter o~ 8 mm has been char~ed with ~ mls (-2
g) of catalyst; in the ~rit fracti.on com~rised between
30 mesh and ~0 mesh of the ~S'rM US~ series~
~ sampler ~or the e~fluent of the reaction is posi-
tioncd downstream o, the reactor and the analysis are
~ade ~aschromatographicallyO
The catalyst is initially fired at 500C for t~ro
hours in a nitro~en ~tream to remove the absorbed water.
~Iethanol is thon fed in at a wei~ht hourly space ~e-
locity (I~JI-ISV) 1.5 ~/~ an hour with an o~en tempcrature
20 o~ 275C and subsequently of 4000C~ , .
The analysis of the reaction o~fluent shows the pre- .
sence of methanol only at both the temperatures indicat-
ed above.'
~IPL~ 8 (~ comparativo e~am~le¦
2~ I`his e~ample is illustrativ~ of the absonce of de-
hydratinO~ propcrties o-~ the modi~ied crystallin~ silica
TRS-23 as pre~arcd accordin~ to.~ample 3 an ~ot thorou~
1~ washed, BO that tIIe concentration of protonic millie-
qui~alents per ~ram of catalyst is as low as lo1 , 10 5
Ey operatirg ~ith the procedura and with the appa-
ratus~escribcd in ~;ample 7 hereo~ thc reactor is chargcd
with ~ m],s (-2.8 ~) of cata,lyst the grit si~e o:~ which is
comprised between 30 and ~0 mesh, ~ST~I US~ series, and
the cata].yst is heated ~or two hours at 500C in a stream
of anh,~drous nitrogen O
~ Iethanol is ~cd in at the temperatures o~ 2l~0C and
300~C and also l~oooc at a wcight hourl~ sp~cc ~clocity
206
ISV) of 1075 ~rams per ~ram an hour.
In all thrce cases J no dimethyl cther is iound in
the reaction efflucnt and only the fed in methanol is
founcl.
~ IP~ 9
This e amplc is illustrativc of the e~.ccllent cata-
lytic dchydratin~ properties of the moclified c~ystalline
silica TRS-22 as prepared according to E~ample 1 hereof
and having a concontration of protonic milliequlva1ents
per ~ram of 1.5 . 10 . By operatin~^ with thc procedure
and the appar~tus as dcscribed in E~ample 7 hcreol~ the
reactor is c~ar~ed with ~ mls (-3,5 g) of ca~aly3t in
the grit fraction comprised between 30 mesh and S0 mesh
of the US~ series o~ ~AST~I~
Upon firing for 2 ho~trs under an anhydrous nitro~en
strcam to~remoYe the adsorbed water~ ~ethanol is ~ed in
at a weight hourly space velocity (1~ISV~ of 1.5 ~/~ an
hour at the reactor temperatures of 250C and 255C
The anal~sis o~ the reactor ef~`luent, which is com-
posed by dimcthyl ether3 unreactecl methanol and water,w~hout ascertainin~ thc presencc of by-products c1ekocta-
ble gaschro~ato~raphically~ gives thc r~sults cabulated
in Tablc 1 h~reof
It can be seen that the crystalline silica accordin~ to
the present invention has an e~celleIlt dehydrating acti-
vity~ with convorsion ~ercentages hi~h~r than those de-
scribcd in the
by thc same ~ssi~nee hereof relating to active al~minas
which have been treated 1~ith silicon compounds.
; 30 It is sufficient t~note that by operatin~ with TRS-
22 at 250C and ~T 2650C~ thero aro o~t~i ned~ with a InISV
of 1.5 convcrsion of methanol ~thich arc~ res~ectively,
equal to~ and hi~cr than~ tnose whic~ can be obtaincd at
300C and with a ~ISV of 1 on active alumina which has
been treatcd l~lth silicon compo~mds.
T ~ B L ~
.,
D ~
- 15 -
Catalyst : TRS-22
Temporature~ ~C 250C 265~C
Prossure, bar
~-ISV in g/g hourly1~5 -105
Conversion of CM30~I
molar ~ ~2 ~ - 88~1
~lPL~ 10 ~ com~arative exam~e)
This e~a~ple is illustrative of t e convorsion of
. tho ~imethyl ethcr in-to hydrocarbons, with a special at-
tention to tho light olefines, on the modified crystal-
line silica TRS-22 as prepared accordin~ to ~.am21e 1
hereof and con-taining sodium cations, so that the con~en-
tration o~ protonic milliequivalents per ~ram of catalyst
is ~.] . 10 ~. -
An electrically heated tubular reactor having a dia-
- meter of S mm (inside) is char~od with 2 ml (=1 g) of a
catalyst havin~ a ~rit size ratin~ between 30 mesh and
80 mcsh of the US~ series o~ AST~I~
The catalyst is heated~ at the outsot, to 550C for
2 hours in a nitro~en stream to remove -the absorbed water,
if anyD Gascous dimethyl ether.is fed by maintaining all
the pi~in~is heated to prevent condonsat-ion. Do~rnstream
of the reactor~ a properly hcated sampling appliance is
installed~ to permit -the introduction o~ the reactor ef-
fluent into a gaschromato~raph.in which the complete a-
nalysis of the reaction ?roducts is carTied outO
30 ~s regards the calculatior of the conversion,.it is
to be borne in mind that the methanol ~rhich is formed by
- partial hydration of the dimethyl ether is consider3d as
an unreacted prodt~ct~ so that the molar conversion is
referred to the dimethyl ethor which has beon converted
into hydrocarbons and carbon mono~idc ~lld carbon dio~ide.
The molar sclrec-tivities on tho products aro rcfcr-
rod to the n~bor of mols of dimcthyl ethor which havo bcen
_ 16 -
convcrted into the inclicated produc~, relative to the
total n~lmber of reacted mols.
The results thus obtainccl are tabulated in Taole ~;
the latter clearly shows that the catalyst in question
is not very active and not vory selectivc 9 too inasmuch
as considerablo amounts of carbon mono~idc and carbon
dio~ide a~cl methane have been formecl~
T ~ ~ L ~ 2
Convorsion of ~lmeth~rl ~th _ drocarbons
Catalyst : TRS-22
.
Test TempO Press. 1~ISV Conversion S~LECTIVITY IM TI~ PR0-
per pass~ DUCTS, molar '
No. ~ bar molar ~CO-~C0 ~C~ C ~IL-C II6-C~
1 375 1 oO652.35.0 14.9 30.1 50.0
2 1~75 1 0.2097.010.9 6.5 2601 56~5
~L~ 11
This example is illustrative of the con~ersion of
the dimethyl ether into hydrocarbons~ with s~ecial at-
; tention to the light olcfines on the modi iod c~rstalli-
nc silica TPS-22 as preparcd accordin~ to e~amplc 1 and
haYin~ a co~centration of 1~5 . 10 protonic milliequi-
valents per ~ram of sample,
By operating with the procedure and the apparatus
as disclosecl in ~xample 9 hereo~, tho reactor is char~ed
with 3 mls (=1~5 g) of catalyst in the grit size range
o~ ~rom 30 mesh and 80 mesh of the ~ST~I US~ series.
The catalyst is pre~io~ls3y heatecl to 550C for 2
hours under a nitrogen stream to remo~e thc absorbecl wa-
ter.
The results which have be~en obtained are tabulatod
in Table 3. The comparison ~lith Table 2 clearl,~ shows
that, as the acidity is varied, the beha~ior of the ca
talyst is ~os;.ti~oly im~rovedO
~3~
7
T,~ E L ~ ~
Conversion of Dimet1~ thc-r into II~-clrocarbons
Catalyst : TRS-22
Test Tenl~. Press. I~SV Conversion SEL~C~IVITY IN '~ PR0-
per pass. ~UCTS, molar ~0
No. C bar molar ~' C'~C~CHI~-C2~ -C3II6-C4
1 305 1 207 3808 0.5 30.1 2t~,3 L15.1
2 335 1 2.7 ~7.9 -5 23.0 1909 56.6
3 365 1 4.7 97.3 -5 19.0 18.8 61~7
365 ~ 6.7 ~7.1~ 0.5 23,.2 19,7 5~.6
l~85 1 6.7 9~.1 0.5 18.3 18.7 61~9
6 l~85 1 ,8.7 87-1 0.5 20.1 1~.2 61.2
7 L~40 1 9.0 92,1 0-5 1~o5 15.2 67.8
E~IPL~ 12
This e~ample is illustrative o~ the acti~ity~ in,the
reaction of alkylation of bcnzene with ethyle~ne, o~ the
c~talyst TRS-22 (1.5 . 10 meq H* per gram).
~ l electrically heated tubular reactor havin~ the
in~ide diameter of 8 mm is chargcd with 1.2 mls (~0.8 g)
o~ catalyst TRS-22 ha~in~ a grit size ~ating from 30 mesh
and 50 mesh, Thrcllgh a meterin~ pump benzene is *irst in-
troduccd in a preheater system-wherein lt mects a prese-
lected rate o~ flo~ of ethyle}le ancl then into thc reac-
-tor, The reaction proclucts are gaschromatogra~hically
analy~ecl. Table l~ tabulates the clata relatin~ tc the
tests which have been carried out.
~ 30'
; Alkylation o:~ ~en~enc with ~th~,~lene
C~t~lyst : ~S-22
Pressure . 20 1~/cm2
Liquid ~Iour1y Space ~elocity~ LI-ISV : l~
35 ~50~ar ratic~ C6I-16:C2~ = 7
z~
~ _ 18 -
Run TempO ,~ molar o~ /~ Molar O:e conversion r~
hours C ethylbenzene diethylbenzcne o~ ethylene
in pr~ducts in products
lO L~l~o13.8 1.50 100.0
5 44013.7 1-55 100~0
100 4413.9 1.l~5 100.0
150 ~'413~9 1,1~ 100,0
200 ~413.8 1.50 100.0
10 250 l~4011.~ 0~80 80.S
300 L~408.2 0.25 51.8
320 1~7011,5 o.7o 76.7
; 350 47010.9 o.65 72.6
400 47010,3 o.60 68.2
1 ) - , ' . '
~XA~L~ 1~
This e~ample is intended to illustrate thc regcnera-
tion o~ the catalysts in question.
More particularly, the catalyst o~ the previotls e-
~ample 12 (TRS-22), af-ter 400 hours of operation, has
been regencrated at 550C, in a properly acljusted air
stream for 5 hours~
On completion o~ the regen~ration run, the system
- is pur~od ~ith nitro~en clurin~ onc hour~ still at 550C,
~hereafter the reac-tion is restartecl under the sam~ con-
di*ions as reported previously.
Tablc 5 reports the clata rclativc to the tests l~hich
have been conducted~
~}
Catalyst : Re~cnerated TI~S-22
Pressure : 203;~/cm2
Licluid lIourly Space Yolocity, Tl-lSV
-~lolar ratio C6h~6:C2II~ : 7
~L3
- 19 -
R~ Tomp . ,' molar o~ ~ molar o~ conversion c'
hours C ethylbenzene diethylbonzenc of ethylene
in products in products
5 10 4l~o 13~ 1 a55 100.0
5 4~0 13.6 1.40- 97-6
100 l~o 13~8 1~,50 100.0
150 1~40 13 ~ 5 100.0
200 ~4 13~7 1~55. 100dO
10250 l~l~o12.2 0.95 83-~
3 ~ 0 10~3 o~60 6S~5
350 ~ O 9 ~ 8 0 ~ 38 62~5
' E~ '
This e:a~ple illustrates the activity~ in the reac-
tion of alkylation of benzene ~ith ethanol, of the cata-
lyst TRS-0.
An ~lectrica].ly heatec1 tubular rcactor of the diame-
ter (inslde) of 8 ~m is char~ecl wi-th 1.Z ~ls (-O.S ~ o~
catalyst havin~ a rit size ran~e o~ fro~ 30 mesh to 50
mesh. Throu~h a meterin~ pt~p thc reaction mi~t~rs is in~
trodueed, ~hich consists o~ ben~ens and ethanol~ in a mo-
lar ratio o~ 5:1~ first in a prehcater and then in the
reactor
The reaction is carried out at 4l~ooC and the reac-
tion products are gaschromato~raphically analy~ed.
In T~ble 6 tho data relative to ths tests ~hich ha~e
been carried out are ta~ulated d
~ -tio
Catalyst : TRS~0
Temperature 1~ 0C
Pressur- ~ 20 l;g/cm2 ~ :
Liqvicl I-Iourly Space Volocity, LIISV : 10
3~ ~Iolar ratio C6II6 C2II~~
1~-3~
- 20 -
Run hours ~ molar of ~ molar of conversion c'
othylbenzene dietihylbenzene of C2II50II
in produets in produets
,
5 50 19.0 1.2 100
100 19~,0 1,,2 100
150 19~0 1~2 100
200. 19~0 1"2 100
- 300 19~0 1 o2 100
10 400 19~0 1.2 100
5 mls of the alumin~-modified silica TRS-20 prepar-
ed as su~ested in ~ample 5 are impre~rnated with an a-
15 queous solution of II2PtCl6 in sueh a ~ay that the contentof Pt in the catalyst is 0.2 ,' by ~t.
Platir~m~ is reduced to the elemental state at 600C
in a hydro~cn stream ancl is introducecd in an electrical-
ly heatecl tubular reaetor havingr an inside diameter of
20 mm.
The capacity of abatin~ the exhaust gases o~ a mo-
tor car is ellecked ~ith two typieal reactions, that is~
oxidation of propylelle to carbon dioxide and o~idation
of earbon monoxide to earbon dioxide.
Test~
The fed in ~ases .~hich are composecl by S00 ppm (parts
per million) of propylene, 8~' of oxygen and the balance
nitro~en~ are preheated to 120C and passecl on the eata-
lyst ~ith Gaseous Hourly Spaee Veloeity, GIISV of ~0~000
hours (reeiproeal hours). Propylenc is convortecl for ~9,~
The same ~aseous ~i~r-ture~ prehcated to 90C i5 fed to the
catalyst at a GHS~ of ~0,000 reciprocal hours and a eon-
version of ~9C~ for pro~ylene is obtaincdO
Te.st E!
The fed in ~ases are eomposed by ~.S ,' of C0, Sf~ of
oxygen and tlle balance nitrogen and are preheatecl to S0.C
and pas3ed on the catalyst at ~ GHS~ of ~O~OOO.reeiproea'.
~3~ )6
- 21 -
hours, the conversion o~ 59,' of C0 being thus obt~ined.
The same ~aseous mi~ture~ prehcatcd to the same tom-
perature is fed to the catalyst at a G~ISV o 50,000 rc-
ciprocal hours and a conversion o~ 99' is obtained for
CO. Thc temperatures indicated abovc~ i.c. from ~0C to
120C~ r..ust be corrcctly rngarded as e:;ceptional since
the best commcrcial catalyst as used in the catalytic
muf~lers carry out the same conversion ratin~s o~ prop~-
lenc and carbon dio~ide at the same space velocities re-
portecl above but at a ~mperature which is nevcr below
150~C.
; E~-~2ll~L~ 16
This cx~ple is for illustrating the activity, in
the reaction of all~ylation of benzene with ethylene~ of
the catalyst T~S-57 as pre~ared accor~ing to the proce-
dure o~ ~ample 6 hereo~.
The reaction i3 carried out in a tubular rcactor of
- the fi~cd-bed type having an inside diameter o~ ~ mm and
electrically heated.
There is introduced in the reactor 1.2 ml ~=0.~5 ~)
of the catalyst, having a grit size rating from 30 mesh
to 50 mesh.
Throu~h a metering pump benzcne is introduced, first
into a prchcater system (where it merges with a preselec~
ted rate of flow of ethylene) ~nd then into the reactor.
The reactor o~fluents are gaschromato~rapIlically analyz-
ed. Table 7 reports the data rela-tive to the tests which
ha~e been carried out.
~Z
~ ylation of Ben~cne wi ~ y~
Catalyst : TRS-57
Prcssure : 20 1~/cm2
Te~erature : ~L~o oc
Liquid EIourly Space Velocity~ ~ISV
~lolar ratio C6I-I6:C~ 7
~31~
- 22 -
Run hours O molar of ~' molar of cor.~.version cO
eth~rlben~ene dicthyl1~cnzcne of ethylene
in products in products
13~9 1.35 100.0
13.9 1'~3$ 100.0
100 11~o 1.30 100.0
150 1308 1~30 98.
200 13.9 1.35 ' 100.0
10 250 13,~ 1~28 . 97.9
300 12.5 1.02 ~7.6
350, 11.3 0.90 '78.9
E~I~L~ 1~
Thc same catalyst T~S~ hich had bcen uscd ~or thc
reaction o~ al1~ylation o~ benzene ~ith ethylcnc as dis-
closed in 1~ample 16~ has bccn subjcctcd to an in situ
rcgcneration run with a stre~m o~ air diluted ~tith ni-
trogon at 500C,
On comnletion o~'the rQ~eneration r~m, -the catalyst
has been sub~ected a,ne~ to the r~action o~ al1~ylation
o* benzene ~ith. ethylcnc. The data tabulatcd in Table S
.are a clear sho~in~ o:~ ho~ simple and advanta~eous is to
regenerate such a catalystO
T ~ 8 L E 8
~ Y____- ~ BenY~ it~ Y1~3
Catalyst : P~e~encrated T~S-57
Pressur^ : 20 l;g/cm2
Tcmperatur~ o C
Liquid IIourly Snace Velocity, LI-ISV
~Iolar ratio C6~I6:C2~I4 : 7
R~1~ hours ~' mvlar of ,~ molar of conversion c'~
ethylbcnæene diethylben~cne of cthylene
in products in products
10 . 1l~0 1.30 lOOoO
23 -
13~9 1.35 100.0
100 1308 ~-4 100~0
150 13.9 1035 100~0
20~ 13~8 1~0 100~0
5 250 13~2 1~19 93.8
300 1208 Or95 88~5
~L~ 18
This e~a~plo illustrates tho acti~ity of the cata-
lyst T~S-~7 as clescribed in F~;am~le 6 for tho reaction
of all~lation of bonzene with ethanol~
~ ~3~2~i
. 24.
The reaction is carried out by introducing in an
electrically heated~ fixed-bed~ tubular reactor~ 1.2 ml
(0.85 g) of the catalyst, ha~ing a grit size r~nge of
from 30 mesh and 50 mesh. ~ia a metering pump~ the
reaction mixture~ which is comprised of benzene, ethanol,
is introduced first into a preheater assembly and then
into the reactor. The effluents are gaschromatographi-
cally analyzed. Table 9 reports the data relative to
the tests which have been carried out.
: 10 T A B L E 9
. ~
`.. -: . ALKYLATION OF BENZENE WITH ETHANOL . -
Catalyst : TRS-57
. Pressure : 20 kg/cm2
Temperature : 440C
Liquid Hourly Space Velocity, LHSV = 10
Molar ratio : C6 6 2 5
Run % molar of ethyl- % molar of diethyl- % conver-
benzene in the benzene in the sion of
products produets C~H50H
18.8 1~3 100
100 19.0 ~.2 100
150 18.8 1.3 100
200 19.0 1~2 100
250 19.0 1.2 100
25 3~ 19.0 1.~ 100
400 19.0 1.~ 100
Quite particular an aspect of application of the
modified silicas according to the present invention~ is
the use of such aluminum-modified silicas as eatalysts
~13~
25~
~n the alkylation of the C4 hydrocarbons~ olefines and/or
paraffins, to hydrocarbons having a high octane numbers.
As outlined above, such modified silicas are porous
and have a specific surface area greater than 150 m /g
and correspond to the general formula reported in the
foregoing.
The following Example 19 is illustrative of this
particular application of the present invention.
EXAMPLE 19
For alkylating isobutane with nor.butenes~ a
porous crystalline silica such as obtained in Example 5
hereof, the crystalline lattice of which aluminum has
been introduced as a replacement for silicon~ is employ-
ed as the catalystO
A small reactor such that described in Example 7
hereo is charged with 3 mls of catalyst ( = 1.9 g)~
having a grit size of from 30 mesh to 50 mesh-. -
The operative condi-tions and the results which
ha~e been ob-tained are tabulated in Table 10 hereunder
T A B L E 10
Pressure : 20 kg/cm
Molar ratio of isobutene to the nor.butenes = 15
_ _ _ _
Temp. LHS~ % alkylation with Composition of
C rec.hrs respect to the the products
butenes
.. _ . . . .
250 1.3 100 about 90% iso-
paraffins ~ about
20% aromatics
_
350 1.3 100 aboùt 50% iso-
paraffins ~ about
50% aromatics
~ . . _ ~
350 5~o 9~ about 70~ iso-
paraffins ~ about
30% a~onlatics
26.
Yet another practical application of the pre-
sent invention is the preparation and use of a zeolite-
type ca-talyst of the class ZSM~5.
It is known from a patent assigned to Mobil,
US 3 702 886, that zeolites of the class ZSM-5 can be
prepared by exploiting deri~atives of silicon, such as
silica-sols, aerosyl-type amorphous silicas, te-traalkyl
orthosilicates, or deriva-tives of aluminum such as sodium
aluminate~ aluminum sulfate~ aluminum acetate, in con-
junction with a quaternary ammonium base such as tetra-
propylammonium hydroxideO
According to a modified embodiment of the present
invention it has been ascertained that zeolites of the
ZSM-5 type can be prepared by exploiting the general
teachings of the invention whenever the material which
monitors the crystallization is an aminoalcohol and
appropriate amounts of compounds of silicon, germanium,
aluminum and gallium are used so that the molar ratios
SiO Al Ge2 A123 Si2 2 3 2 2 3
are comprised between 5 and 100 and are preferably in
the vicinity of 35.
A z~olite prepared according to the present in-
v~ntion has an X-ray diffraction spectrum akin to that
of zeolite ZSM-5 and corresponds to the general formula :
. 25 .9 ~ 0.2 ~2/n W203 5-100 Y02 : ~H20
wherein M is a cation selected from among H and/or
NH4 and/or metallic cations and/or cations deriving from
- amino alcohols~ especially ethanolamines~ n is the va--
lency of such cation, W is selected from the group con-
3o sisting of aluminum and gallium, Y is selected f~om
the group consisting of silicon or germanium and z is
between 0 and 40.
27.
The preferred form of this zeolite provides W
as aluminum, Y as silicon with a ratio of silica to
alumina comprised between 10 and 60.
The preparation of the preferred zeolite accord-
ing to the present invention is carried out by admix-
ing the reactants within the following ra~ios~ express-
ed in terms of mols of oxides.
Ratios Broad interval Preferred Interval
OH /SiO2 0.2 - o.8 o.3 - o.6
T.~.T.A./T.E.T.A.+Na o.3 - o.8 Oo4 - o.6
H20/OH- 10 ~ 100 20 - 40
wherein T.E.T.A. stands for the amino alcohols~ more par-
- ticularly triethanolamine.
~he process according to this particular aspect
of the present invention provides for the following
- step sequence :
A derivative of silicon or of germanium and a
derivative of aluminum or gallium is reacted, in an
aqueous~ alcoholic of hydroalcoholic solution~ with an
ami~o alcoholj such as the e-thanolamines anl more par-ti-
cularly triethanolamine, adding possibly one or more mine-
ralizing agents such as hydroxides andfor halides of al-
kali metals or alkaline earth mstals to encourage cry-
stallization.
The mixture is allowed to crystallize in an enclo-
-~ sure for a period from a few hours to many days at a high
temperature, from 150C to 250C and preferably from 170C
to 210C for a period o-E time of from 2 to 10 days~ gene- -
rally one week, allowed to cool and, upon collection on
a filter and washing with deionized water~ the crystals
~L~3~2~
28.
are dried and fired in air at a temperature comprised
betwcen 300C and 700C, preerably a-t 550C, for a
period of from 2 hours to 24 hours, whereafter a re-
peated cationic exchange is effected with an ammonium
S salt, preferably ammonium nitrate or acetate~ washing
with dist. water and fired once again as described above,
if the product is desired in the form H .
The zeolite thus preparsd can be used as such,
or diluted in an appropriate dilution ratio and supple-
mented with one or more elements having catalytic promo-
ting actlvity, according to the procedures and other
methods provirled for the zeolites of the ZSM-5 class.
A few examples~ numbered from 20 to 22 inclusive
are intended better to illustrate -this particular embo-
diment of the invention which is connected with the
zeolite-type catalysts.
EXAMPLE 20
This example illustrates the preparation of the
zeolite ZSM-5 by using triethanoamine~
A Pyrex-glass vessel rnaintained in a G02-free
atmosphere is charged with 60 g of Al(N03)3.9H20 dis-
sol~ed in 400 mls of 95%-ethanol~ then there are added
uith stirring 600 g of tetraethyl orthosilicate. As
soon as the solution becomes limpid, there are added
200 g of triethanolamine dissolved in 400 mls of dist~
water and the mixture is heated~ s~ill with stirring,
to 600Co After 30 additional minutes, there is added
a solution of 13 g of NaOH in 200 mls of dist. water,
and~ after 30 further minutes there are added 22 g of an
NaOH supplement (total 35 g of NaOH) dissolved in 400
mls water. ~ massive formation of gel is observed : a
z~
29.
~vigorous stirring is started and is maintained during
a few hours~ while concurrently raising the temperature
to 90C so as to dispel all the ethanol, both intro-
duced in the reaction and formed by h~drolysis. At
this stage, the reaction mixture is transferred to a
3-litre stainless steel autoclave and the hydrothermal
treatment at 195C is started~ to be maintained for the
duration of 9 days.
The resultant product is then allowed to cool at
room temperature, collected on a filter, washed many-a
time with very hot distilled water and dried at 120C.
The solid is then fired at 550C for 16 hours
and is shifted to the ~1 form by repeated e~change in
; hot condikion t950C) with ammonium acetate (or nitrate)
and by firing again at 550C for 6 hours.
The X-ray d~ffraction spectrum corresponds to that
reported by Table I of the US pat Specn~ 3 ,02 886.
~XAMPLE 21
_
By adopting the same procedure as in Example 20,
there are reacted 880 g of tetramethyl orthosillcateg
120 g of Al(N03)3.9H20, 400 g of triethanolamine which
had previously been dissolved in 800 mls of water~ 7~ g
-of NaOH in 700 mls of water and the mixture is made up
to a volume of about 9 litres by adding dist~ water with
very vigorous a stirring. The mixture is concentrated
at the temperature of 80C for about 30 hours until re-
ducing the volume of the liquor to about 5 litres in total.
The hydrothermal treatment is effected during 8 days at
190C in a stainless steel autoclave, equipped with a
stirrer.
The X-ray diffraction spectrum corresponds to that
3L2(~
- 30.
of ZSM-5 and the specific surface area is 380 m /g.
The ratio SiO2 : A1203 is 38-
EXA~LE 22
9.6 g of sodium aluminate and 10 g o potas-
sium hydroxide are dissolved in 200 mls of water. Theclear solution is supplemented with 208 g of triethanol-
amine~ dissolved in 1~000 mls of water. The solution
thus obtained is allowed to stand, with stirring, under
an inert gas blanket~ for two hours at 80C. There are
now added~ as a ¢rystallization-encouraging agent, 40 g
of potassium bromide dissolved in 150 mls of water.
There are now added slowly 345 g of Ludox colloi-
dal silica (40% SiO2) dissolved in 1~500 mls of water.
The resultant gel is allowecl to age ~or 24 hours at 90C
under an inert gas stream.
The gel thus treated is then crystallized in a
stainless steel autocla~e for 10 days at 198C.
~ The procedure illustrated in Example 20 is comple-
; ted and zeolite ZSM-5 is thus obtained.
