Note: Descriptions are shown in the official language in which they were submitted.
Back~round of the_Invention
Field of the Invention
This invention pertains to catalyst material for
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expediting the oxidation of an olefin to the corresponding
oxirane; and, more particularly to a catalyst material of
a boron containing substance for catalyzing the liquid phase
epoxidation of olefins with organic hydroperoxides.
Prior Art
Oxiranes or epoxides,while being valuable commercial
products in and of themselves,are also commercially valuable
as starting reactants for synthesizing many useful compounds
such as polyether polyols for urethane systems. Over the
years many methods have been disclosed for synthesizing such
compounds. The majority of these methods involve the oxidation
of the corresponding olefin. For example, it is known that
ethylene can be converted to the corresponding epoxide by a
vapor phase partial oxidation with molecular oxygen over a
lS silver catalyst. However, the ease of olefin oxidation
varies greatly depending upon the size and structure of
the olefinic starting reactant and therefore many of the
disclosed processes are not effective for epoxiding olefins
in general.
~ecently it has been disclosed that olefinically
unsaturated organic compounds can be oxidiæed to the
corresponding oxirane compound in liquid phase with organic
hydroperoxides in the presence of various catalysts. For
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example, U. S. Pate~t 3,350,422 issued October 31, 1967 to
Kollar discloses that soluble vanadium compounds can be
employed as a homogeneous catalyst for oxidation of olefins
with organic hydroperoxide. Specifically, hydrocarbon
soluble organometallic compounds of vanadium are disclosed
as being effective as epoxidation catalysts. However, the
insoluble vanadium catalysts, such as for example, vanadium
pentoxide are disclosed as substantially ineffective in
catalyzing the epoxidation of propylene. More recently,
U. S. 3,634,464 issued January 11, 1972 to Wulff, et al.
describes the use of oxides of molybdenum on a solid
inorganic oxide support modified by inclusion therew~th of
bismuth or certain rare earth metal oxides as a catalyst
for the epoxidation of olefins with an organic hydroperoxide.
The catalyst is substantially insoluble in the epoxidation
reactant mixture, providing a heterogeneous system. The
presence of a minor proportion of bismuth or certain rare
earth oxides as catalyst modifiers is disclcs ed as a critical
feature of the catalytic action.
Additionally, it has been disclosed that silicides
or siliceous solids having high surface to mass ratio are
particularly effective as catalytic substances in the
epoxidation of olefins with organic hydroperoxides.
Specifically, U. S. Patent 3,702,855 issued November 14, 1972
to Bell et al. discloses a catalytic material selected from
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metal silicides of titanium, zirconium, vanadium, mobium,
chromium, molybdenum, and tungsten is effective as a liquid
phase epoxidation catalysts.
More recently it has been disclosed in U. S.
Patent 3,832,363 issued August 27, 1974 to Fetterly et al.
that the epoxidation of ethylenic compounds to the corres-
ponding oxirane compound is catalyzed by the presence of
a boron oxide, a dehydrated boric acid, and the hydrocarbyl
esters thereo~. The compounds disclosed in this patent which
are useful as catalysts contain at least one B-0-B linkage.
The previously described catalysts suffer from one
or more disadvantages when employed as liquid phase epoxidation
catalysts. For example, many of the previcusly known catalyst
materials are expensive and difficult to prepare, and/or are
highly selective to oxidation of specific olefinic compounds,
and/or are difficult to use requiring special apparatus or
highly selective reaction conditions, and/or are limited to
heterogeneous or homogeneous type reaction systems.
Unexpectedly it has been found that a large class
of boron containing substances are effective in catalyzing
liquid phase epoxidation of an olefin with an organic hydro-
peroxide to the corresponding oxirane. These substances may
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be generally categorized as binary and ternary boride compounds
consisting of boron and at least one element selected from groups
II-A, III-B, IV~B, V-B, VI-B, VII-B, VIII, III-A, IV-A and V-A
of the periodic Table, the rare earths and the actinides.
Because of the wide range of boron containing substances effec~
tive in catalyzing liquid phase epoxidation of an olefin with an
organic hydroperoxide, the catalyst may be selected to form a
substantially heterogeneous system with the reactants or a sub-
stantially homogeneous system with the reactants. Further,
boron containing substances of the instant invention are easily
obtainable, relatively inexpensive and easy to handle. Because
of the wide range of boron substances which are shown catalytic-
ally active, a particular compound can be matched to a particular
epoxidation reaction thus achieving somewhat superior selectivity
and yield. Mixtures of these boron substances can also be used
to afford specific selectivity.
Summary of the Invention
According to the present invention, there is provided
a method for the liquid phase epoxidation of an olefin having
from about 2 to about 60 carbon atoms with an organic hydro-
peroxide comprising the step of: intimately contacting the
said olefin with said organic hydroperoxide at a temperature
of about 25 to about 200 C and at a pressure of from autogenous
to about 200 atmospheres thereby maintaining the product and
reactants substantially in liquid phase in the presence of a
catalytically effective amount of a binary boride consisting
of boron and a material selected from the group consisting of
nitrogen, carbon, silicon, calcium, aluminum, lanthanum,
tungsten, molybdenum, chromium, manganese, cerium, zirconium,
vanadium, niobium, tantalum, nickel, and uranium, wherein the
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molar ratio of the olefin to the hydroperoxide is from about
1:10 to 100:1 and wherein the molar ratio of hydroperoxide to
the said binary boride is from about 1:1 to 10,000:1.
Preferably, the binary boride is selected from the
group consisting of LaB6, CeB6, ZrB2, NbB, TaB, TaB2, WB, MnB,
NiB AlB2~ AlB12, B4C, B12C3, Si4, Sis6, 6 2 5
CrB, CrB2, CrB3, Cr5B3, MoB, MoB2, ZrB12, and VB2.
Detailed Description of the Preferred Embodiment
The catalyst materials in accordance with a pre- -
ferred embodiment are those boron containing substances which
are not substantially dissolved or attacked by the reactants or
product mixtures under the reaction conditions encountered in
the epoxidation of olefinic compound to the coxresponding
oxirane with organic hydroperoxides. These catalyst materials
may be generally employed in the liquid phase heterogeneous
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epoxidation systems wherein organic compounds having at least
one aliphatic olefinically unsaturated carbon-carbon bond
and from 2 to 60 carbon atoms are oxidized with an organic
hydroperoxide. Further, a preferred epoxidation is carried
out in the presence of certain borides as hereinafter
particularly described in the presence of reactants and
under conditions as further set forth herein.
Catalyst Materials
The catalysts used within the scope of the instant
invention are generally boron containing substances effective
in catalyzing the liquid phase epoxidation of an olefin with
an organic hydroperoxide. These substances are characterized
as boride compounds of boron and at least one element
selected from group II-A, III-B, IV-B, V-B, VI-B, VII-B,
VIII, III-A, IV-A and V-A of the Periodic Table, the rare
earth and the actinides. More particularly these boride
compounds may be either the so-called binary borides or the
ternary borides. The binary borides may be represented by
the general formula MXBy wherein B is boron; M is an element
selected as above; x is an integer from 1 to 5; B is boron
and y is an integer from 1 to 12. The ternary borides may
be represented by the general formula M~ByRz wherein M, x,
B and y represent elements or integers as described herein
above, R is an element selected from the same periodic
groupings as M but is an element different from M in any
given compound and z is an integer from 1 to 5.
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The preferred catalytic materials are the binary
borides. The preferred binary boride compounds are those
catalysts which are not dissolved or attacked by the reaction
mixtures containing the organic hydroperoxides, olefins, and
products. The preferred catalytic materials thus form substan-
tially heterogeneous systems with the liquid reactants and
products. Preferred catalysts are LaB6, CeB6, ZrB2, NbB, WB,
W2Bs MnB, NiB, AlB2, and AlB12. Other examples of boride
compounds useful as insoluble catalysts are CaB6, TiB2, ZrB12,
~fB2, TaB2~ FeB, Co3B, Co2B, CoB, SiB4, SiB6, and B4C.
It should be noted that the empirical formulas given
herein do not necessarily represent the exact stoichiometry of
the catalytic material but rather represent particular crystal-
line phases which may be nonstoichiometric due to lattice defects,
vacant sites and the like. It is intended that the scope of the
instant invention cover all of the so-called binary and ternary
borides represented by the formulas set out herein above, which
include but are not limited to borides having isolated boron
atoms such as for example M4B, M3B, M2B, M5B2 and M7B3; borides
having single and double chains of boron atoms, i.e. those
crystalline structures where a boron, boron linkage exist such
as M3B2 and M4B3 and M3B4; borides having two dim~nsional nets
such as those represented by the formula MB2 and M2B5; and borides
having a three dimensional boron network such as those having the
formulas MB4, MB6, and MB12.
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As used herein, solubility and insolubility are
relative terms. That is, those boron containing compounds
which are characterized as forming heterogeneous systems may
be in fact somewhat soluble in the reaction mixtures. Likewise,
so-called soluble boron containing substances may not form a
completely homogeneous single phase with the reactants and
reaction products. When utilizing the so-called soluble boron
containing substances, it is preferable that sufficient
catalyst be used to create a heterogeneous system.
The exact physical form of the catalyst is not
important. It may be used as a powder, lumps, pellets,
spheres, and the like; as adherent films on metals or other
supports; and as coatings on s~-pports such as alumina silica
or clay. Additionally, the catalyst of the instant invention
may be extruded or compressed to various shapes as to form a
combination with adhering materials such as binders, fillers,
extenders, and the like.
Additionally, it will be realized by those skilled
in the art that mixtures of one or more of the boride catalytic
material may be used to pro~ide, for example, selectivity in
epoxidizing certain olefinic compounds.
Olefinicallv Un~a~olaCed Reactants
The olefinically unsaturated materials which can be
epoxidized in accordance with the invention are generally
organic compounds having at least one aliphatic olefinically
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unsaturated carbon-carbon double bond containing from 2 to
about 60 carbon atoms. In fact there are no known
olefinically unsaturated organic compounds which cannot be
utilized within the scope of the instant invention. For
example, the olefinic reactant may be of acyclic, monocyclic,
bicyclic, or polycyclic olefin and may be a monoolefin, or
a polyolefin. Additionally, the olefinic linkages of the
polyolefins may be conjugated or nonconjugated. Further,
the olefinic reactant may be a hydrocarbon or a substituted
hydrocarbon with functional groups containing, for example,
oxygen, halogen, nitrogen, or sulfur. Typical substituted
functional groups are hydroxy groups; ether groups; ester
groups; halogens such as chlorine and florine; nitrile
groups; amide groups; sulfur containing groups; ni~rate
groups; and the like. Examples of suitable olefinic
reactants include ethylene, propylene, isobutylene, hexene-2,
octene-l, eicosene-l, pipyrlene, vinylcyclohexene, dicyclo-
pentadiene, styrene, allyl chloride, allyl alcohol, allyl
acetate, allyl ether, allyl cyanide, cyclohexenecarbonitrile,
soy bean oil, cotton seed oil and the like.
Organic Hydroperoxides
The organic hydroperoxides which can be used within
the scope of the instant invention are broadly any organic
compound having at least one hydroperoxide moiety but free
of functional groups which are deleterious to the epoxidation
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reaction or are normally reactive with the hydroperoxides.
A group o~ useful hydroperoxides is represented by the
fonmula R'-OOH wherein R' is a hydrocarbyl or a substituted
hydrocarbyl group containing from 3 to 20 carbon atoms.
The hydrocarbyl group may be alkylaryl, alkyl or substituted
alkyl or arylalkyl. The substituted alkyl or arylalkyl
hydrocarbyl can contain oxygen incorporated into the
functional group such as hydroxy, hydrocarbyloxy, hydro-
carbyloxycarbonyl, hydrocarboyloxy, and the like.
Additionally, the hydrocarbyl or substituted hydrocarbyl
can contain halogens, e.g., chlorine, florine, bromine and
iodine.
The most preferred hydroperoxides are secondary
and tertiary hydroperoxides containing up to about 15 carbon
atoms such as tertiary butyl hydroperoxide, tertiary amyl
hydroperoxide, cyclohexene hydroperoxide, tetralin hydro-
peroxide, cumene hydroperoxide, diisopropyl benzenehydro-
peroxide, c~-methyl benzylhydroperoxide, and the like.
Reaction Conditions
The epoxidation process of the instant invention
is conducted in the liquid phase at lower temperatures,
e.g. 25C to 200C and pressures sufficient to maintain the
reactants and products substantially in solution. The mode
of conducting the process of this invention is not critical and
may be accomplished by conventional methods such as batch~ con-
tlnuous or semi-continuous reactions. The temperature range at
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which the epoxidation reaction is carried out will depend
upon the reactant and the catalyst employed but generally
temperatures in the range from about 25C to 200C and
preferably temperatures of about 50C to about 150C are
found sufficient. The reaction pressures are generally
those which are required to maintain the reactants, products,
and the like substantially in liquid phase. Pressures which
range from autogenous to about 200 atmospheres are generally
sufficient for carrying out the instant process.
The amount of reactants present in the reaction
mixtures will generally depend upon the olefin to be
epoxidized and the hydroperoxide; but, generally molar
ratios of olefin to hydroperoxide of from about 1:10 to
100:1 and preferably from 1:2 to 10:1 have been found
sufficient. Additionally, the molar ratios of hydroperoxide
to the catalyst material will likewise depend upon the boron
containing substance used, the olefin, the hydroperoxide
and the reaction condition. Generally molar ratios of
hydroperoxide to catalyst from about 1:1 to 10,000:1 have
2~ been found sufficient, and preferably molar ratios of 1:1
to 1,000:1 are utilized.
Although it is not necessary, diluents and/or
solvents which are liquid at reaction temperatures
and pressures and are substantially nondeleterious
under reaction conditions to the reactant and products
may be utilized. Useful solvents and diluents
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include aliphatic or aromatic hydrocarbons, alcohols,
ethers, and esters. Aliphatic and aromatic halogenated
hydrocarbons may also be utilized. Examples of suitable
solvents include tertiary butyl alcohol~ octane, cyclo-
hexane, benzene, toluene, ethyl benzene, dichloromethane,ethylene dichloride~ propylene dichloride, chlorobenzene,
and the like.
Additionally, additives such as antioxidants and
inorganic bases may be added to the reaction mixture if
desired. Examples of such additives are di-t-butyl-p-cresol,
p-methoxyphenol, diphenylamine, sodium oxide, magnesium
oxide, and the like. Additives of these types are
particularly useful for preventing undesirable side reactions.
The epoxidation reaction is suitably conducted by
any of a variety of procedures. In accordance with one
procedure the olefin~c reactant and the catalyst are initially
charged into a suitable vessel equipped for reflux at
autogenous pressure. The vessel is heated to reaction
temperatures and hydroperoxide is then added incremently
with constant stirring. In another method, the reaction is
effected in a continuous manner such as by contacting the
olefin reactant and the organic hydroperoxide, in the presence
of a solid catalyst which may be supported on a medium. In
accordance wlth another method~ the catalyst and the
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hydroperoxide in a suitable solvent may be charged into an
autoclave which is sealed and flushed with nitrogen~ The
olefinic compound is then pressured into the sealed
autoclave and the reaction mixture heated to reaction
temperatures and stirred while reaction pressures are
maintained. This method is particularly suited to gaseous
olefinic campounds such as ethylene and propylene.
At the conclusion of the reaction, the product
mixture can be separated and the product reco~ered by
conventional methods such as fractional distillation9
selective extraction,filtration, and the like. Further,
the catalyst, unreacted reactants, solvents and diluents
if such are used can be recycled.
To further illustrate the process and the catalyst
of the instant invention the following examples are provided
not as limitation but by further way of demonstrating the
details of the invention.
Example 1
In this example, the liquid phase epoxidation of an
olefinic compound with an organic hydroperoxide was carried out
in the presence of a catalytic amount of a boron containing
substance in accordance with the instant invention. A 250 ml.
flask equipped with a stirrer, thermometer, reflux condenser
and dropping funnel was charged with 84 g. octene-l and 1 g.
tungsten boride ~WR). The charged mixture was heated to 90C
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and 90% tertiary butyl hydroperoxide was added dropwise until
a total of 25 g. had been added. The reaction mixture was
then heated at reflux (108-110C) for 220 minutes with
stirring. The heated mixture was all~wed to cool and then
the crude reaction product was analyzed. The analysis
indicated a 36% yield of octene oxide based on the amount
of charged hydroperoxide. The crude reaction product was
filtered by conventional methods and the resulting filtrate
was analyzed for metal content by atomic absorption analysis.
No metals were detected in the filtrate.
Example 2-30
In these examples, various boron containing
substances were used to catalyze the liquid phase epoxidation
of octene-l with tertiary butyl hydroperoxide by the pro~
cedure of Example 1. The results are shown iII Table I.
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TABLE I
Selec~ivity Selectivity
(based on (based on
Moles Conversion hydro- converted
5Catalyst Moles hydro- Time, hydro- peroxide) octene)
Example (wt. g)_ octene peroxide Hours peroxide to epoxide S2
2 LaB6(1) 0.375 0.125 6.0 82% 20% 88%
3 CeB6(1) 0.375 0.125 5.0 90% 87~ 94%
4 T;B2(1) 0.75 0.25 7O0 16% 18% 40%
ZrB2(3) 0.75 0.125 6.0 89% 87% 92%
6 NbB(3) 0.75 0~125 7.0 89% 91% 91%
7 TaB(l) 0.375 0.125 6.0 73% 15% 90%
8 TaB2(1) 0.375 0.125 6.0 62% 16% 78%
9 WB(2) 0.75 0.125 7.0 86% 92% 92%
MnB(3) 0.75 0.125 6.0 52% 27% 84%
11 Co3B-
Co2B(1) 0.375 0.125 3.0 96% 15% 88%
12 CoB(l) 0.375 0.125 5.0 92% 29% 90%
13 NiB(l) 0.375 0.125 6.0 68% 81% 93%
14 FeB(2) 0.375 0.125 6.0 45% 22% 86%
AlB2(3) 0.75 0.125 6.0 68% 88% 89%
16 AlB12(1) 0O375 0.125 5.0 95% >90% 94%
17 B12C3(1) 0.375 0.125 6.0 47% 10% 74%
18 SiB4(1) 0.75 0.125 5.0 76% 42% 83%
19 SiB6(1) 0.375 0.125' 6.0 66% 18% 92%
BN(l) 0.375 0.125 6.0 47% 10% 89%
21 CaB~(l) 0.375 0.125 6.0 65% 23% 86%
22 W2B5(2) 0.375 0.125 6.0 75% 81% 94%
23 VB2(1) 0.375 0.125 3.0 99% 49% 93%
24 CrB(2) 1.25 0.25 4.0 80% 14% 55%
CrB2(1) 0.375 0.125 5.0 82% 21% 73%
26 Cr5B3(1) 0.375 0.125 6.0 86% 19% 69%
27 MoB(l~ 1.50 0.50 1.75 95% 82% 87%
28 MoB2(1) 0.75 0.25 2.0 98% 71% 94%
29 ZrB12(2) 0.375 0.125 6.0 81% 53% 90%
UB2~2) 0.375 0.125 6.0 95~ 11% 67%
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Example 31
In this example, propylene oxide was prepared in
accordance with the instant invention. A stirred one liter
autoclave was charged with 2 g. of tungsten boride ~WB), 50 g.
tertiary butyl hydroperoxide, and 100 g. tertiary butanol.
The autoclave was sealed and flushed with nitrogen. Then
84 g. of propylene were pressured into the sealed autoclave
and the reaction mixture was heated with stirring at 118 to
122C for 4 hours. The pressure maintained in the autoclave
during the reaction sequence was substantially autogenous.
Propylene oxide yield values using GLC A% analysis were ~65%.
Example 32
In this example, the procedure in Example 31 was
repeated with the exception that the solvent used was 100 g.
benzene instead of the tertiary butanol. Propylene oxide
yield values using ~LC A% were~90%.
Example 33
In this example, the procedure in Example 31 was
repeated with the exception that the solvent was 100 g.
propylene dichloride instead of the tertiary butanol.
Propylene oxide yield values using GLC A% were ~90%.
~xample 34
In this example octene oxide was prepared by a method
similar to that of Example 1 with the excep~ion that 25 g. of
cumene hydroperoxide was used as the epoxidizing agent instead
of tertiary butyl hydroperoxide. A significant yield of octene
oxide was observed.
~0~ ;4
Example 35
In this example, N-octene oxide was prepared by
the method of Example 34 with the exception that aluminum
dodecaboride (AlB12) was utilized as a catalyst instead of
tungsten boride~ A significant yield of octene oxide was
observed.
Examples 36-39
In each of the following examples branched chain
and cyclic ~lefinic compounds were epoxidized in accordance
with the inventlon, using the procedures as set out in
Example 1. The following epoxides were prepared from the
corresponding olefin by reaction with tertiary butyl hydro-
peroxide in the presence of a catalytic amount of tungsten
boride (WB~. The results are shown in Table II.
TA8LE II
Catalyst Hydroperoxide Selectivity
Tungsten Tertiary epoxide
Boride Butyl Conversion. (based on
Olefin (g) g g_ }~ydroperoxide ~y__o~eroxide)
2036 Vinyl-
cyclohexene 1)
(42) 4 10 91% 93%
37 Allyl Acetate 2)
(32) 4 10 10% 80%
25 38 3-Cyclohexene
Carbonitrile 2)
(17) 4 8 52% 90%
39 Dicyclo-
pentadiene 2)
30(60) 4 10 92% 39%
1) Analysis based upon GLC area %
2) Analysis based upon titration-wt %
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Example 40
In this example epichlorohydrin was produced in
accordance with the instant invention. A glass pressure
bottle fitted with a stirrer was charged with 100 g.allyl-
chloride, 25 g.90% t-butylhydroperoxide and 3 g.tungsten
boride (WB). The charged mass was heated to 108C-110C
with stirring and held for 24 hours. The pressures maintained
during the reaction sequence was autogenous. Recoverable
amounts of epichlorohydrin were observed~
Example 41
In this example ethylene oxide was produced in
accordance with the instant invention. A stirred one liter
autoclave was charged with 12 g. aluminum dodecaboride (AlB
50 g. tertiary butyl hydroperoxide and 150 g. tertiary butyl
alcohol. The autoclave was sealed and flushed with ethylene
and pressurized. The autoclave was heated to 110C and a
pressure of 800 psig maintained for 4 hours. During this
period, the temperature range of the reaction mixture varied
.. ..
from about 109C-112~C. The effluent reaction product
mixture showed recoverable amounts of ethylene oxide.
While the invention has been explained in relation
to its preferred embodiment, it is to be understood that
various modifications thereof will become apparent to those
s~illed in the art upon reading the specification and is
intended to cover such modifications as fall within the
scope of the appended claims.
What is claimed is:
