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Патент USA US2408165

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Sept. 24, 1946. '
2,408,164
31m April 25, 1942 -
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36E
6BR.
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2 Sheets-Sheet" 1
Patented ‘Sept. '24, 1946 Y '
“
archigrosteif, nartiesviugokiai 'a'ssign'ort‘toy"
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vi
Phillips Petroleum} Compa'nyga“ cjorp'oratlonfjol
Delaware
7 > I.Iantiaaaita;z;. 194a,seriaiuoruoséi .,
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" '1 2,403,164
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1:111:clams? (Ortiz-Lassa)‘
' 'Ifhis‘invention‘relatesfbroad lyiwlihé-ptepara7
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i
idealist
> very‘ ?nely; comminuted
,
tion or catalytic materials‘. and‘ more speci?cally .
nely , pulverized; ‘catalysts
_may be employed
em91,0Y§!1-'-,
advantageously
.
wherehthelstock
to the shaping of materialsfpossessing, catalytic I‘ ~~State~is
activity into suitable flor‘rrls'vtorenderv them_more
is allowed ton'percolateupwardly,or downwardly ‘
_ ;through, a bed of; ?ne catalyst 1 Wher'eby;';very,/in-.
emrci'en‘t fog-,u'se in‘thejvarious purposesto whichv
\‘ they. are ?pplied'i .1 The; “inveniipn relates more, timate vcontact i-is pbt'ained, waHowever, this . mode .
’ : particularly to the preparation of catalytic, masses
of operation :is; frequently subject to;-;th_e disad
‘of compounds 'whichpo's'sesst'he property of co.
vantages that "channeling" takes] placeand that
hering in rigid. self'esupport'ing units under con t a portion. of the‘ bed is washed away/in 'the treat
I ditions hereinafter speci?ed; the'form of the units‘. '10,‘ ed e?luent; stream.‘ 1 Also {the pressureldrop
‘ permitting the catalyst “and ‘catalyzedf-rnaterial ” ' through ' a (mass; of ‘the cattiilys?ls‘ ,_.eXCeSS_ive. j .7, 1
to come into _ oser and :more' e?ective. contact ,
' ‘ Alternatively;?nely-divided?
during reaction. .
' 'In the ."e'ntlre history’ ' oi. catalysis ’ one.’
atalyst-may be
mixed with a liquid, either the’lid'uid. bei'n‘gft'reat
the
Jed’ orsan auxiliary slurry-forming liqui
‘
major problems ' .has'j'lbeen ,that vof i'bringingthe
resulting suspension v‘or, slurry pumped through a
catalyst : into intimate,~.,e?ective; contact; with. the " ' ' reaction zone .1 where ' itiis' exposed to the "condi
.
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a
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'15
v'chajrge material tobecatalyzedand or maintain
.tion‘s"‘adjudge'd best ioncarrying ‘out the reac
tion: This operating system is-‘comm'only' desig
ing its surface so that .this'intimate, contact mayv
be continued fora satisfactorily, longvjyperiodyrpof nated the "?uidcatalyst’t‘method; However, this
time. i ‘The, longer‘ a" catalyst can ' be- maintained 20
method of handling the~catalyst requires either
with a ‘free, active surfacelforcontact with the ,
‘that the catalyst be settled out to' separateit
charge'material the longer operation may con
from‘ the'reactio'n mixture and‘ the charge stock
tinue without time-‘consuming revivi?cationsteps
or the residue-from‘ the‘reacti'on,’ or that the em‘ I
being necessary and the more e?lcientis thezop
eration. According to one theory widely accepted
(see ‘fca'talysia?’ _ by . Be‘rkrnan, Morrell ;and_ Eg-v
tire liquid-material .in' whatever condition ‘ it‘ may
25 lexist'be'vapo‘rized or‘?ltered o? fromithe cata- ‘
lyst, or that'other special meansbe employedjto
loff), catalysis is a surface phenomenon. vCata
lytic activity isbelieved to be due toiunsaturated
or unsatis?ed valence forces'ln atoms," by virtue
of their position with respect to other atoms in
the materialgf'l’hese "forces are ,belicvedxto be
smallest within‘ the body 0f ftheimateriétl, greater
remove the treated liquid'from the catalyst which
may then he?r'eused, regenerated or ‘discarded -'
30
.asdesired.
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' Charge stocks" in vapor form ‘may also, be
‘brought into‘ contact with‘ a’fflnely divided cata
near and at the surfaces’ where'these forces. are ,
unbalanced,‘ and greatest‘ on the edges and‘, at
lyst, although again-inmany cases‘ channeling
'of ‘the thro vgh-p'a_ssir_'lg vaporsgoccurs'ywith in
points‘; A _‘rrjiaterial amorphousin physical make .35
up'is' believed'to be more actiyecat'aIyticalIy than 1 ‘
.
if used in crystalline form; sinceincrystaIs sec
‘?nelydivided'catalyst calls for special methods > I
e?lcient results. " , '
Another‘ di?l'culty 'ls’vthatf'handling‘ the spent a‘
and equipmentv ‘for vits. rejuvenationsince gem
ondary forces or valences‘areconsidered to be
erallyitj‘is (not, practicablefto regenerate apow- directed toward the crystal’s‘ center, ,whereas in
,,
n
, v
_
..
amorphous bodies these val'ences fare directedtO- , 40 ,dered catalyst‘in situ.‘
' Anothenmetho'd or preparing catalysts hereto~
ward the outside of‘ the'unitpimaterial. ",l‘here-v
fore. employed is, that‘ of pressing, extruding lor
fore ‘it is necessary that there- ,be maintained‘ the
‘otherwiseiforcinga granular or' powdered catalyst
largest practicablesurface ‘area whichmay be
broughtinto 'contactiwith the‘ material tobe I materialintc various shapes under certain con
catalyzed.‘ In the case of'a'liquid ‘orvap'or'eata 45 [ditions in anliendeavor to insure thematerialre
infinite'tan'd is limited theoretically only byth‘e _. regeneration or revivi?cation. , I These forms - may
be’ rods; cylinders, spheres, spools, etc. OfVariOUS
number of molecules in the catalyst. When deal
__shapes, sizes, ‘dimensions and proportions.» The
ing wlth'a solid catalyst, therefore, itisdesirable
to'use it'ina form'which'presehts the, greatest
main purposes ‘of. this procedure are four:- ('1)‘
‘ lyst, the‘ ‘surface 1con'tactfarea‘, approaches a the ‘ ,,taining the resulting shapeuuringreaction, and _
practicable surface area, so'that "the greatest pro- ‘ ‘ to, permit'ea'sy' handling;z(2).;to;increase the,con-_
vtact ’surface‘_..of._a given amqunt'of cata1yst;~(3) 1
portion of ' the catalyst in the reaction. zone ac
tually takes part in‘ catalyzing the ‘reaction an n
the highest catalysteivllciencyispobtained.‘
, .
Furthermore‘, the irne'th’odiof, ‘handling "and ap
plying the catalyst to‘janyglvenxpurpose is 'dic
tated by the'physIcaI condition‘jof the catalyst
55
to improve the passageor liquidor vaporthrough
the. catalyst while. increasing the length- of; time
between regenerations; and,..(43)_ ginlthe; case of
vrelatively volatilefc'atalyst, suchas metal'halides,
to prevent otminlmizecatalyst losses‘by, volatili
zation. However, theresulting shapes do not have
adequate strength,- rigidity,- crushing resistance,
contact area presented; Therefore, where'prac7~ 60 res'istancen'to abrasion, upon handling, and re
and the requirements of‘ theburpose. The more
?nely divided a catalyst mass is,j_the greatenthe
'
4.
passage of re?ux orother liquid over and around
the catalyst- pieces facilitates .removal of this
; tarry blanket by means of solvents or other means
sistance to thermal shock upon being used in
conversion and during regeneration. >
I
In hydrocarbon conversions at elevated tem
peratures over solid catalysts, one always-present
result is the deposition of carbon on the surface :
which may be employed.
Still another vobject of
this invention. is to facilitate removal of unde
of the catalyst. This carbonaceous coating soon
sirable side-reaction ‘products or foreign matter
_ blankets the surface of the catalyst, ane‘cessitat- ' ‘ ~
ing removal of the coating before the catalyst can
continue to promote the reaction. In some com'-..
from ‘the catalyst.
Porosity is an. extremely important character
» istic
The more highly porous a
a catalyst.
mercial operations now well-known to the in
dustry the active life of the catalyst is only three
catalyst “mass'thei greater the ratio of contact
surface to weight or volume of catalyst, and the
to ten minutes “on-stream” after which‘ the car- ‘
more e?icient-the ‘catalyst per unit of mass. Some
materials are obtainable in crystalline form, or
in‘ otherv form which maintains interstices
bon is removed by burning, to reactivate the mass
and permit efficient operation of the process. The
extra equipment required for this revivi?cation
operation and the time lost- from productive-op
eration‘ during the regeneration part of the cycle
throughout the ‘mass through which fluids may
' pass and thus come into contact more intimately
with a greater catalyst surface. Other‘materials
are'more amorphous in physical form or crystal
lize in such form‘as to‘make'angessentially im
provision of catalyst in forms which’ permit easier
and quicker removal of waste» and deleterious 20 pervious massof the catalyst in bulk. Prepara
ftion of a solid catalyst, ‘in pellet ,form, for. exam
material formed‘ during the reaction cycle
a
adds .greatly‘to the cost‘of the operation. The
ne
ple,~in such manner that- the ‘pellet is composed
main object of» this invention‘, therefore, is‘to
provide a'form of catalyst from which extraneous
of an aggregation of either'porous or non-porous
' distinct advantage in any’catalytic process.
matter maybe removed by combustion, by sol
particles of irregular shapeywlth interstices be
25 tween; and ‘without ‘the use of a, compressive or
other force strong enough to crush'the individual
vents or by other‘ means with the ‘maximum of
ease, simplicity and at a minimum cost in time
and money.
particles results in a pellet having high‘porosity
and comparatively high compressive ‘strength.
'
» . Another problem faced by'the operator. of _a
Such a catalyst is far more e?iclent than. a pel
catalytic unit is that of placing :the‘ catalyst in '30 leted catalyst iof‘e'ither. crystalline or amorphous
material in a‘?nely ‘divided state, ‘which presents
the reaction chamberinsu‘ch manner that all
portions of the catalyst are brought into, contact
only the outer surface of the individual pellet,
‘or the outer surface plus‘ microscopic ,or sub
with the reaction materials in the same degree.
microscopic pores as contact areaDAn ‘object of
It ‘the form and condition of the catalyst mass, or
this invention is to prepare such'a highly‘ eflicient
and comparatively'rugged' type of catalyst.
units of which that mass is composed, are such
that the catalyst can “pack” together at irregu
lar intervals, presenting little space for passage
of liquid or vapor, the resultis that the charge
Numerous other objects will be obvious from
the description given herein. _
channels in passing through, overworking part
of the catalyst while the remainder, in the closely 40
packed sections, remains out of contact with the
charge, resulting in ‘inefficient, expensive oper
ation. Another object of this invention, there
In the accompanying drawings;
Fig. 1 illustrates typical catalyst shapes into
which the'catalyst may be formed by the process
of vthe invention.
‘
'
Fig. '2 is a macroscopic fragmentary section of
a catalyst shape‘prepared byfthe invention.
fore, is to provide a catalyst form which pre
vents or _minimizes channeling and bringsv all
parts of the catalyst into comparatively equal
In accordance with my invention, in one aspect,
a mass of catalyst particles is shaped by exerting
contact with the charge stock.
mechanical pressure thereupon while the parti
,
y
In the use of volatile catalysts such as metal
cles are heated to a temperature suchv as to cause
bonding of the particles atv the points ‘of ‘contact
stannous, and titanium chlorides, the inevitable 50 under'the pressureexerted. This causes bond
result of reactions carried out at moderately ele
ing of the particles by welding or fusion at the
chlorides, for example, aluminum, ferric, stannic,
vated temperatures is a continuous loss of cata
points of contact [and prevents ?lling, obstruc
lyst by volatilization with a'gradual choking of
tion‘, or destruction of the voids between the
vapor and condenser lines and contamination of
the product with the condensed catalyst. An
additional object of the present‘invention is‘ to
prevent volatilization of solid or liquid catalysts,
the vaporization points of which lie‘in' or near
the temperature range of the reaction, by pre
paring such catalysts in solid briquette-typ
‘forms in a‘ special manner.
‘p
One _characteristic of some metal halide cata
lysts used to promote hydrocarbon reactions is
catalyst particles. Upon cooling and/or releas
ing the pressure, preferably substantially simul
taneously; a rigid, catalyst body is obtained which
‘may advantageously be used in packing a catalyst
tower. The resulting‘body retainssubstant'ially
the porosity of the originallgranular or powdered
>mass because the original ‘voids between con
tiguous particles or‘ granules are maintained and
additionally because the conditions of tempera
ture during forming are' preferably‘ such as to
prevent‘ superficial fusion or glazing, of the sur
forms on the surface. effectually blanketing the 65 face other than at the edges, points, or areas
that, as reaction continues, a tarry, unctuous mass
catalyst and preventing it from "exercising its
in ‘contact; ‘This is‘ attained by vthe use of
mechanical pressure “such that it is, possible to
over a properly formed ‘catalyst as a liquid or
effect fusion at the points of contact at a tem
?lm or if the reaction products formed are liquid
perature substantially below‘th'at at which actual
at the operating‘ temperature, the flow of this 70 melting at atmospheric pressure or under the
nquidi will tend to remove this tarry material as
mere static pressure of the mass due to the force
fast as it is formed, preventing the blanketing
of gravity or on the non-touching areas, takes
effect on the reaction. If the charge stock flows
effect so detrimental to efficient catalyst activity.
Or, if- only vapors are present in contact with the
catalyst, the presence of uniform spaces for the
place.
.
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.
‘
.
Thus my inventiontakes advantage of the
75 phenomenon whereby, upon pressing together two
_ ‘2,400,104
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and the impregnated mass. may be formed into
‘solid surfaces into contact with one another at
any desired shapes in the same manner that the
elevated temperature, bonding is e?ectedi below
thenormal melting-of saidsolldxat atmospheric.
solid material isiformedi '
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pressure.‘ Accordingly the'gforegoing-objects are
’
Any.singlelmaterial.orycompound or any mix
dling and‘ use and Jyetnot ' materially, reduced ' in _
‘ sired- degree and then formed in‘ accordance with
attained inVa' simple and ‘economical .manner. 5 "ture of solid materials may be vshaped in accord
. ance with'my invention. For example,’ Silica "and
The temperature; pressure, '- and time of sub
alumina maybe precipitated separately from so
c'jection to the particular temperaturerand pres,- '
‘lutions of suitable asaltstandi then mixed mechan- '
‘sure employed should be so icorrelated'that the
.ica'lly; but’ preferably mixed l solutions are pre
product obtained is strong, rigid, and‘highly. re
sistant to ‘crushing ' or powdering. during "han :10 cipitatedv together, washed and [dried to any de
porosity (either in inter-‘particle voids or 'in‘super
?cial‘porosity Yof 'eachiparticle orsgranule)‘ as
compared to a pellet ma‘de by'simple'compression .
the invention}: Solids which are‘ not obtainable.
thoroughlyl'admixed with/other'solid's maybe so
mixed by mechanical means: by addingthe two.
16 or more materialsv in crystal or amorphous form
.
~
:My process maybe carried ‘out by pelleting the . to a ball mill, rod mill, orother .pulverizing unit
in case it is desired to grind the materials to
granular or pOWderedLcrystalIine or amorphous
' ?ner comminution -or--to :a container equipped
solid, catalytic material,-_ as; in “ a,‘ pelleting w‘ma
with paddles, stirrerspbr a‘ muller, orv other ap
chine, at su?'iciently‘ elevated pressure‘ and ' tem
at'ordinary temperature:
' paratus for mixing pulverized soIidsand-theop
particles and thereby effect weldingvoribonding. ' eration continued-until the desired intimacy of
but insu?lcient to destroyer materially change ' I mixing is attained, after which the mass maybe
~ the granular, crystalline or other structure of the _ formed'into any desired shape of catalyst units
perature to cause incipientfusing ofthe catalyst
fin accordance with theinyentiom
particles and insu?icient to causesubstantial re
~
: '
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,
25'“ Illustrative forms into which catalysts may be
duction in porosity.“ ‘Thus the individual par
ticles are vcoalesced into homogeneous rigid'forms -
in which the original'ist'ructure and size of the
shaped are shownv in Fig. .1 of the accompanying
drawings. Many other forms‘and'shapes may be
v employed, the prime prerequisite being that as
- vfar as practicable the catalyst'pellets be ‘so shaped
ature employed may be'far" below the ‘normal 30 that they will not pack in the'tower'or ltr'ayor
other support so‘as to :permit channeling of the
’ melting temperature :of the'catalyst.
~ ‘Frequenly'the conditions of treatment are such . ?uid passingthrough the bed, andso that’ “bridg
ing" of passageways by'undesirable by-products
- that no detectable ‘fusion‘takes pla'c'e'. "Neverthe
particles‘ is essentially unchanged.
f
"
If the pressure is s'u?lciently high, ‘the temper
occurs :to a'minimumV-degree. The ideal catalyst
timate bond in which there is no line of contact, 35 pellet is one which exposes a'maximum' surface
less there is;formed an extremely strong and in
evenithough incipientv‘fusion' may- rlotatitually
have taken place. '
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H
y
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' ‘The mechanical pressure exerted , serves to
causebonding of the particles at their points‘and
to‘, contact per unit of ‘catalyst weightior volume,
and one‘ which‘cannot be .packed'in such a way
as ‘to, cause channeling. The various [proposed
. forms are designed to promote the e?lciency of
vareas of contact'without subjecting the rest of 4o the ‘catalyst in- these two factors especially, and '
' the particle, i. e., the main body of the catalyst,v , the choice of any"‘given'form‘ or combination? of
to an increased pressure over that prevailing in
'forms'is determined by the‘conditions to be met
the gaseous atmosphere ofi-thenetwork of voids,
which will usually‘be substantially atmospheric.‘
‘in the use of the catalyst£~=
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> Instead of- relatively small shapes such as pel-‘
Thus fusion ‘takes place at most at the‘contact 45lets, I may prepar'eimassive shapes such as sad
rings,’ discs, plates, etc. Use of regular
‘point without glazing of the main area'?of the '_ Ydles,
geometrical shapes minimizes’ packing in a catacatalystparticles.
V
g
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_
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i
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\
. " The‘mechanical ‘pressure‘employed'mayrange
from one additional atmosphere, ixei, 'lp5_"lbs."per
sq. in., upwardly. Preferably pressures of atfleast
' ‘100 lbs; per sq. in. arefemployedu' Pressures rang
, ing'as high as 10.-000flbs.~per sq. in. maybe used.
through‘a; c‘atalyst‘bedl-
" “
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1Methods‘f‘o! preparation of catalysts in ac
cordancewith "'thisinvention will be determined l"
by} the: nature of, the catalyst, its ‘physical and
chemical-properties, and by ‘the requirementsof
vthe'jfir'iishetl“product. For the purpose of?out
catalyst being treated. ‘It should be su?lcie‘nt
under the conditions of time _and temperature. 55'_lining the invention, catalysts may be'divided.
Thepressure will depend upon- 'I the particular
employed to causeithe bonding described above‘
but insu?icient to cause crushing of the ‘individ
into two general classes: '(1‘) catalysts which are
fusible, wholly or‘partially at moderately ele
vated temperatures not excessivelyv above those
ual particle'or granule. Thus; for less hard cata- .
, to be employed in fashioning the pellet and (2)
lysts such as aluminum chloride, very low‘ pres
sures will ordinarily» be used‘, but for hard‘ rigid 60 those which are ‘relatively infusible except at
. temperatures much higher than those normally
materials, such as those containing‘a large per
centage of ‘ silica, extremely ‘ high pressures may
beusedp
1,
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> The principles of this’inventlon are applicable
"to any type of- solid material which maybe em
ployed for catalytic purposes and’ which possesses’
the property uponv T-heating undermechariical
pressure of joining, welding‘or binding at a‘ tem
,
lys't' chamber and» ‘results vina'low ' pressure “drop
considered‘economical.
.
.
v
v
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I
Typical vof the fusible class oi catalysts are
the metal chlorides, the so-called Friedel-Crafts
(is-catalysts. ' At elevated temperatures, especially'in
the vicinity 01' their melting points, or even at
temperatures considerably lower than their vmelt
ing points but well above atmospherictempera
tures I. haveyfound that these materials possess
perature "substantially below 'its‘i'normal melting
temperature. Thus'iit ‘may be applied to any 70 the inherent property, varying in: degree with
di?erentcompounds; of coalescing suiliciently at
solid material or mixture of materials used in
moderately elevated temperature and preferably
catalysis. In- the case of; liquid catalysts such
under moderate pressure to from rigid bodies or
as titanium tetrachloridejor'stannic chloride'th‘e
forms which may be used as such with resultant
liquid may be sprayed, ?lmed or coated on a solid
catalytic material or on'an inert “carrier material 75 greater ease‘i'n'handling and greater‘emciency
2,409,104
7
K ‘8
products selectively or to absorb foreign matter
in the charge stock or reaction ?uids, matter such
in use as catalysts. Incipient melting, or a sof
tening of the outer edges or surfacesof crystals
or of amorphous bodies of the catalyst appears
in practice to yield a condition of the material
which acts as a binding medium to. agglomerate
as water vapor or liquid, tars, sulfur or other
contaminants present or for any other purpose,
such as a catalystpromoter or an inhibitor of
the particles into a rigid mass whichmay be
undesirable'side reactions. In this case the aux
iliary material may be pulverized to any desired
handled as a unit and which will retain its form
at any temperature below the melting point of
degree, which may or may not be the'same as the
the original material and will not be substantial
state of subdivision of the main catalyst, the two
ly abraded or worn away by ordinary careful 10 pulverulent materials are intimately mixed me
chanically, and the mass subjected to the desired
handling under the mechanical conditions ordi
narily applied to solid catalysts. Physical at
temperature and pressure conditions to produce
the finished pellet. The temperature-pressure
trition of the catalyst form or removal of it by
conditions are regulated in view of the physical
vaporization or melting occurs at the surfaces
and edges and is minimized by the compact rigid 15 characteristics of the two materials as they are
form employed. The tendency is to retain the
when only one material is being treated. The
general unit form duringthis attrition process,
primary and essential requirement is that the
compressed and heated mass form a satisfactory
so that the catalyst remains approximately in
such unit form throughout its life.
pellet for the conditions under whichit is to be
1 A general principle of pelleting these catalysts, 20 used, and temperature and pressure are controlled
therefore, is to place the material in crystal,
amorphous, granular or ground form under high
to further that end.
melting point of the material the shorter is the
time and the lower the pressure required to form
a suitable product. Also, the nearer the temper
ature employed to the melting point the more
entation of temperatures, pressures and lengths
of time for heating cannot be given. However,
Frequently, in fact gen
erally, a mixture of. materialsespecially in crys
pressure and at elevated temperature in a moldy
talline form melts at temperaures lower than the
ing or shaping machine where it is forced into
melting point 'of either material, in which case
the shape desired, to form a pellet or unit of the 25 control of the temperaturemust be careful and
required rigidity and physical ruggedness for the
exact and the time of heating must be carefully
purpose. .A large variety of shaping andpellet
controlled in order to avoid going further than
the mere incipient melting which by trial and er
ing machines is well-known to the art, and the
speci?c means and equipment for carrying out
ror is determined as the best condition for form
this purpose is not a part of this invention. The 30 ing the catalyst mass of the characteristics de
temperature and pressure employed are deter
sired. These conditions will vary for each,com
mined by the nature of the catalytic material and
bination of‘ two or more materials, and foreach
the ruggedness required in the ?nished product.
combination of percentages of each in the mix
Generally the nearer the temperature to the
ture. For these reasons a comprehensive pres
the selection of suitable operating conditions for
the carrying out of the invention will be obvious
to those skilled ‘in, the art ‘in the light of this
‘ compact, less porous the resulting pellet is and
the less the effective contact area of the catalyst 40
is, especially when charge stocks are treated in
liquid form where penetration into the small,
macroscopic interstices of the mass increases
materially the effective contact area. Conditions
description.
I
.
When properly mixed, it using two or more
materials, or when satisfactorily pulverized, the
catalytic material may be introduced into a heat
ler, preferably on a moving conveyor such as a
of preparation of‘v the catalyst mass are therefore
belt or buckets, and heated for the required time
at the desired maximum temperature, being ex
posed to the temperature for a predetermined
time to eilect the requireddegree of softening or
incipient melting. This heater may be a narrow,
enclosed space heated externally by any conven
a compromise between compactness and rugged
ness, on the one hand, and catalyst e?iciency and
the largest practicable contact area, on the other.
Wide variations in catalyst ruggedness and po
rosity may be obtained, and the determination‘
—of conditions of preparation will be made in the
light of the requirements for the ?nished catalyst.
In the following table are given- the melting
and the boiling points of the metal halides most
widely used as catalysts inhydrocarbon catalysis.
ient means or the material in its container or
conveyor may pass through a streamlorf hot gases,
such as ?ue gas low in oxygen content, to raise
it to the‘desired temperature. Generally rapid
heating bygases or an oven at a temperature
wellabove that desired in the catalyst a prefer
-
Compound
Aluminum chloride, AlCh __________ __
-
Boiling point
Melting
° F.
‘’ F.
irregular small particles will be heated above the
361
l 374
Aluminum bromide, AlBn __________ ..
505
207. 5
Ferric chloride, FeCla..--.
599
540
Aluminum iodide, A111.
680
376
Zirconium chloride, ZrC
572
i 572
Stannic chloride, SnCh.
_
Titanium chloride, TiCI4__.
Zinc chloride, ZnCi: ................. __
237
277
—27
—22
l, 350
504
.
able since by so doing the edges of crystals or of '
point
l 7.5 atmospheres pressure.
1 Suhlimes.
Frequently it is desirable to include larger or
smaller percentages of other catalytic or rela
tively inert materials with the primary catalyst
to be pelleted. The addition agents may be for
the purpose of improving the bond which holds
average temperature of the mass to provide the
desired bonding condition of g the surfaces.
When the material has reached the required con
dition it is immediately transferred to the molds
or dies, care being taken that it does not lose any
65
appreciable temperature in vthe process, and is
immediately subjected to pressure sufficient to
form a pellet of the desired rigidity, density and
mechanical strength. Methods and equipment
for forming pellets of any desired shape and size
are old in the art and form no part of this in- '
vention. Pressures may vary widely, the value
depending on the materials processed, tempera
tures employed and the requirements for the
?nished pellet.
.
the ?nely divided catalyst material together, it
A preferred way of operating is to subject the
may be for the purpose of absorbing side-reaction 75 mass of powdered or granular, crystalline or
2,408,164
9.
" amorphous catalyst-simultaneously to heat and s >
.
' ,’ pressure, each of the requisite degree-for the pe- "
Jriod of time necessary to effect fusion, welding
,
-
,
1ov
,
,
passed into a jacketed hopper maintained at 300
325" F'.,~fromvwhich it'is measured automatically
‘into dies-Vina plunger press and subjected to a
and bonding at thepointaedges or areas.of.con-‘ ‘ " pressure or 25' to 100 pounds per square inch. The
tact only and. without substantial reduction in T
resultant pellets, which may be in the form of
volume of voids between the particles.» This op- '
"perforated cylinders 1/2 inch long'by %-inch di
oration may. be. carried out‘in" any suitable appa- ‘
ameter‘ are‘-v dumped on an asbestos-?ber coated
belt and allowed to cool while passing through a
ratus. Where relatively small shapes are de
sired, the process may be effected in a pelleting
‘ tunnel in abreeze of cold ?ue'gas.
The vformed
pelletsi‘will-retain‘ their shape with ‘only slight
machineprovided with means for bringing the
catalyst to the required temperature, for holding‘
~ shattering of “edges when dumped" repeatedly on .
. it there during the _ compression or shaping vun
. a mass'of the same pellets frorn'a height of three
der pressure and for cooling the resulting shapes ' ‘ I
feetat atmospheric temperature.
andmeleaslngfthe pressure." Preferably cooling
and release of pressure take place simultaneous» '_
'1 ‘ Q‘
ly. If, desired the cooling may be [effected by‘
v
I
,7
'
EXAMPLE
2
,
o
.
,. Two hundred.» ?fty (250) pounds of anhydrous
y releasing or electing the pellets through a coo.1 - ~
. zirconium chloride, ZrCh, and‘20‘pounds' of 16430
mesh alu'minayAlzOz, are mixed‘intimately in a
ing zone where they are cooled by a cooling ?uid.‘
'In manycasesmere ejection of the pellets into‘
revolving tumbler drum, and heated, by hot flue
‘ - the. atmosphere ~‘effe'cts simultaneous Cooling ‘and 20 gas to 540-'550°‘F.~' for about 30 seconds and then '
release of ‘pressure 'su?lciently to cause the pellets ,
pelleted in a “rounded diamond” die press at es~
. to retain their shape ‘upon handling, upon’ paci<--:v I sentially .the same" temperature and at 50-100
Ping intoa bed, and during conversion‘v therewith; . ' pounds per square inch.‘ After coolingto atmos
pheric temperature'these briquettes, Tag-inch by
In the case of'larger forms, ‘the selection of
'
%-inch,»withstood- eight cyclesjof loading in a
reaction chamber, reaction'period, removal from
suitable apparatus will be within the‘ skill of. .
‘ ‘ workers in the art in the lightof the foregoing;
' The size of the particles orgranules of catalyst. I
chamber». and regeneration, with very little attri
1 material treated in accordance with my invention
tionloss.
may vary widely, from say 200‘imesh‘ up to several '
inches in average diameter. ' It is preferred to 30
use initial material so graded in accordance with
known principles as," to give substantial inter
'
»
-
-
Somewhat different conditions obtain when
pelleting metal oxides, sul?des and salts with
I considerably ’ higher melting
points.
particle voids i. e. at least, 20%‘ by volume of voids.v
sul?des and salts‘ frequentlyemployed as cat
Frequently particles of substantially the same
.;_alysts in di?erent‘processes involving hydrocar
size will be most desirable.
,
s;
.
l
a
m 1
bon reactions."
In the case of highly volatile hygroscopic metal
" halide catalysts, especially1aluminum>chloride, it
is frequently desirable to blend therewith a‘min'or
‘
primarily catalytic, for'example alkaline earth
‘
‘
"
-
V
“
. any traces of ,watertherefrom,
.
‘
-
I '
'
'
'
v
‘
45'
.
Alumina,
,
.
Melting
point
'
A]lO|__.-_'_ .‘..-‘..'_
°
. . . _ . . _ _ . . . _ . . _ _ . _ _.
Aluminum sul?de, ails“. '
,
with metal-halidecatalysts, and thus obtaining a ‘_
sintered mass if held‘ under pressure,'or 01' vol
-
385
1, 643 (d;
Cupric oxide, GuO
l, 879 ((1.
Iron oxlde,'~~Fez0a_ ;
2. 849
_
l, 292
. Mercuric chloride, 'Hg'Glaui'.
,,Mo1_vbdenum trioxide; M001"
529
1. 463 v
Nickelous oxide, NiO.» ..... .l
3, 794 o ‘
529
Silicon‘dioxide,$01.11....
' Strontium chloride, 51-0
Strontium nitrate, Sr (N 03) a
3, 110
1, 603
l, 058
‘Thorium oxide, Thor“- ‘
5.072
60 Tungsten trioxide. W0:
Vanadium tetraoxide, V
:_ lyroughened or corrugated to increase the surface - " Zinc oxiIle.'ZnO._ .4 l__._
_
~ Zirconium oxide’, Zl‘Oz _______ ..»__v ....... .‘.__._; ____ _.
of the, pellet‘ or shape. As shown-in Fig. "1, the *
pellets may be of almost any form, such as cylin- ' *
.drical with large ratio of inner diameter to outer '
a of longitudinal holes therethrough ' to increase
contact surface.
"
H
‘
"
'
came 1]
Two, hundred (‘200), ‘pounds of , anhydrous’ alu- :
minum chlorideand 10 pounds of calcium chlo
ride are crushed .between corrugated rolls :until
90 per cent will'pass a 1_6-mesh ‘screen. and are
> then passed through any oven via conveyorbelt,
heated by radiation to 325° F. for 20 seconds and
1,045'
._ Phosphoruspcntasul?de, P18
'I'hesurfaces-of the mold may be advantageous-'
e. .diameter. .The cylinders may have'a multiplicity
1 703
1,630
l, 153
l, 306
t_ Manganese sulfate, MnSOL,
Phosphorus pentoxidc, P105.
...a bond which,;under‘the pressure vof the‘ forming ' '
porous structure of the catalyst. : }
3, 614'
Lithium chloride, LiCl __..
' Magnesium chloride, MgCl¢_
atilizing too large quantities of the material at
die, cements the-particles together without’ clos-‘
v,ing the macroscopic openings-or destroying the
1, 422
e,- O '
\Lead bromide PbBl‘z
Lead oxide, Ph0.__'.____
4, 082
1, 195
777
Cobaltic‘oxrde, 00,0:
. be‘ taken to avoid toomuch melting, ‘particularly. 50
’ ‘atmospheric. pressure.“- ,As' stated above, ‘melting
must be at most‘ incipient; barely enough to‘ form
Chromium trio:
F.
2,012
Calcium chloride, 0:01:
The examples given below are illustrative only, ~ " Cesium
chloride, CsCL;
and this invention is in no wise to-be‘ limited by ‘ Cesium nitrate. GINO;
Chromium oxi e, CnOr
these examples which merely‘ illustrate without
limiting-the Principle of the process. Care must
s
‘
‘if’mm‘md
melting» point and lower the ‘.vapor pressure of '1
the aluminum chloride and also acts to remove ‘
'
2.
-'
'
chlorides, for, example calcium chlorideor mag; ‘I "
‘
'
Table
' .5813 used as catalysts.“
40
, nesiumchloride. This material acts to raiseft'he
'
'
'
MeItingpointsofmetaI oxides,‘ sul?des, and
percentage. of another metal halide which is not I '
,
‘Table 2
shows the melting-points of various metal oxides,
2,. 683
'l, 573
3, 272
5. 400
11.681" l<'.. B. P." "
' ' _'When‘ the incipient’ melting point of the cat
"alyst in; for example‘, a ?nely or coarsely pul
verized state is higher than the temperature to
1 whichit-isipracticable to heat thematerial, it
I-bBCOmGS desirable’to employ another or binding '
material of lower melting'p'oint, admixed with
the‘ prim'ary'catalytic material, to obtain ‘the ad
“ vantages, of-porous structure, strength and easy
‘and convenient ‘handling soughtv in this inven
tion. The binder material may be catalytically
inert or preferably may have a promoter or ac- '
2,408,104.
11
12
tivator effect on the primary catalyst. Many
metal oxides, such as silica, alumina, chromic ox
ide, etc., may be precipitated from solutions of
process. Or, the two solid materials may be
mixed intimately by mechanical means and the
their salts, washed and dried and may be used
as such in pulverized or lump form as effective
operation continued as with the dry mixture re
ferred to above. iGenerally such a mixture of
catalysts, the degree of subdivision being deter
materials shows a melting point considerably be
low that exhibited by either product alone, and
the lower temperature of heating‘required to pro
mined by the conditions of drying, or by the par
ticle size obtained by crushing, grinding, etc. after
the drying.
1
fusion, followed by pelleting by any acceptable
. duce the desired state makes for a less expensive
More frequently, however, solid catalysts so 10 operation. The following examples illustrate the
prepared and used in accordance with prior prac
principle without limiting in any way its appli
tice possess the disadvantage of small surface per
cation.
'
unit of weight or volume, if the catalyst is re
Examine 3
tained in relatively large lumps or masses, or
Five hundred (500) pounds of unsintered, black
that of too close packing and too high resistance 15
chromic oxide is crushed to pass a 12-20 mesh
to the ?ow of ?uids therethrough when employed
screen and mixed with ?ve per cent of ?nely
in a state of fine pulverization. In the case of
ground
molybdic oxide and the mixture heated
formation of tarry deposits on the catalyst, the
while passing slowly through a mu?ie furnace to
?nely divided mass may become entirely impervi
1000-1200° F., the mix being maintained at the
ous to the passage of ?uids in a relatively short
maximum temperature for a period not exceed
reaction period, necessitating frequent regenera
ing about 15 seconds. Without cooling the mix
tion with consequenttime loss and unit e?iciency
ture appreciably, it is measured into a die press,
reduction. If such catalysts are made into paste
the dies being heated to800-l000" F., and sub
form and in this condition rolled, pressed or ex
jected
to a pressure of ‘100 pounds per square inch
truded to desired shapes, the drying of the formed 25
for a period of ten seconds. The pellets, cylinders
paste may have the eifect of forming a binder
of corrugated outer wall 1/2~ll'lCh - outer and
eifect tending to retain the desired shape. This
14-inch inner diameter, are cooled to room tem
method has the disadvantage of destroying in
perature
on an asbestos-surfaced belt while pass
large measure the macroscopic or microscopic
porous condition in which otherwise the catalyst 30 ing through a tunnel in a blast of c00led arid ?ue
gas and are stored in closed bins until ready for
may be found, resulting in a considerable decrease
in catalyst e?lciency.
use.
,
.
‘ExAMrLE 4
These disadvantages are largely eliminated or
minimized by following the principles of this in
vention. A metal hydroxide, such as alumina,
silica, chromic oxide or similar material may be
precipitated from solution by any of the methods
well known in the art. A mixture of two or more
Granulated nickelous oxide is covered with a
saturated aqueous solution of cesium chloride, the
excess solution allowed to drain off and the mass
dried at 250° F. The impregnated oxide is heated
in a neutralatmosphere to as high as 1000° F.
such catalytic materials may be precipitated in
average temperature by direct radiation of heat
intimate mixture, and the mixture ?ltered off, 40 on the surface of the granulated mass, maintained
dried and pulverized by any satisfactory means.
in a thin bed l/2-inch thick, for 10-20 seconds.
Or, a mixture of hydroxides, oxides or of sul?des
The massis measured into a heated die press and
may be precipitated in intimate mixture, one
formed‘ into perforated cylinders under a pressure
component being of high melting point and the
‘of 100 pounds per square inch during a period
other of relatively low melting point. The mixed 45 of approximately 10 seconds, is cooled in a dry
precipitates may be washed and dried in the con
ventional manner and pulverized to any desired
degree of ?neness in a suitablemlll or grinder.
The degree of ?neness of the particles is dictated
neutral atmosphere and stored in the same at—
mosphere until ready for use.
I
claim:
,
'
1. A process of forming a substantially rugged
by the conditions under-which the catalyst is to 50 and pervious ‘mass of a solid catalytic material
be employed, especially by the nature of the un
comprising a normally solid Friedel-Crafts metal
halide catalyst, which comprises heating a par
desirable by~products which are formed during
reaction.
ticulate mixture comprising solid particles of such
In the case of a single catalytic product of low
a metal halide, and containing at least 20% by
melting point, such as cesium nitrate, lead bro 55 volume of inter-particle voids, to a temperature
mide, phosphorus pentoxide, or molybdenum
below the meltingpoint' of. the components of
trioxide, etc., the material may be'exposed to a
said mixture and, while the particles are main
temperature approaching its melting point long
enough to produce the required incipient fusing,
tainedat such temperature, subjecting said mix
ture to a mechanical pressure just sufficient to
and then while at said temperature formed into 60 effect incipient fusing of said particles at their
pellets of the desired shape in a die maintained
points of contact without substantial melting or
at the required temperature for forming a satis
disintegration of said particles and without sub
factory produ'ct. ‘ When pelleting the higher
stantial reduction in volume of voids between the
particles.
‘
melting materials such as chromic oxide, alumina,
iron oxide or thoria, it is desirable to include 65
2. A process of forming a substantially rugged
therewith a relatively small percentage of a
and pervious mass of asolid catalytic material
lower-melting material which may also have some
comprising solid aluminum chloride, which com
catalytic effect, as lead oxide, manganese sulfate,
prises heating a particulate mixture comprising
or molybdic oxide, to give a. mixture which reaches
solid particles of aluminum chloride, and contain
its incipient fusing point at a lower temperature. 70 ing at least 20% by volume of inter-particle voids.
This lower-melting material may be added in
to a temperature below“ the melting point of
small quantity by saturating the metal oxide or
aluminum chloride and, while the particles are
other material with a saturated solution of the
maintained at such temperature, subjecting said
material, the excess solution allowed to drain of!
mixture to a mechanical pressure just sufficient
and the mass dried and heated to incipient 75 to effect incipient fusing of said particles at their
2,408,104
points of contact without substantial melting or
disintegration of said‘ particles and without sub
stantial reduction in volume of voids between the
particles.
‘Y
‘
‘
I
'
l
3. A process of forming a substantially rugged
and pervious mass, of formed ‘catalyst particles,
consisting of a mixture ofpaluminum chloride and
calcium chloride, which comprises heating a mix
ture of solid particles of aluminum chloride‘and
of calcium chloride, and containing at least 20% 10
by volume of inter-particle voids, to a tempera
ture below the melting point and within the range ,
of approximately 300°‘ to approximately 325° F.‘
and, while the particles are maintained at such
temperature, molding a mass of the particles
under a mechanical pressure within the range of
approximately 25 to'approxlmately 100 pounds
per square inch to effect bonding of the particles
only at the points‘ of contact thereof without
substantial disintegration of the particles and
without substantial reduction in volume of voids
between the particles. v
ARCH L. FOSTER.
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