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Патент USA US3019185

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Jan. 30, 1962
3,019,175
A. J. HAEFNER ETAL
MANUFACTURE OF 1,1,1-TRICHLOROETHANE
Filed Dec. 51, 1959
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32
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smarts‘
Patented Jan. 30, 1962
2
3,019,175
MANUFACTURE 6F 1,1,1-TRiCHLQROETHANE
Albert .l. Haefner and Franklin Conrad, Baton Rouge,
La, assignors to Ethyl Corporation, New York, N.Y.,
a corporation of Delaware
this ratio is greatly increased, e.g., up to about 15:1 and
greater.
The photochemical chlorination reaction of 1,1-dichlo
roethane is carried out in the presence of a directive
5 chlorination reaction medium-win, a solvent or com
plexing agent, the presence of which alters the normal
distribution of products and favors or increases the forma
tion of the more unsymmetrical 1,1,1-trichloroethane.
This invention relates to a process for the manufacture
By the use of this directive chlorination reaction medium
of 1,1,1-trichloroethane, particularly to a directive photo 10 the chlorine complexes with, for example, a solvent
chemical chlorination method for the production of this
molecule and creates this directive e?ect. The directive
Filed Dec. 31, 1959, Ser. No. 863,180
4 Claims. (Cl. 204—163)
chlorinated hydrocarbon.
'
chlorination reaction medium, as stated, need not neces~
Prior art techniques have relied on thermal and ordi
nary photochemical chlorination reactions for the manu
sarily be a solvent but can even be an additivev added to
an inert liquid medium or diluent. Though the method
facture of methyl chloroform, or 1,1,l-trichloroethane. 15 of this invention—-viz., chlorination by use of the direc
In all such techniques, a large amount of chlorinated by
tive chlorination reaction medium—is mentioned with
products is concurrently produced. These competing
reference to a photochemical chlorination which is a
reactions, producing in particular considerable amounts of
1,1,2-trichloroethane, have thus largely deterred commer
highly preferred embodiment, the method is also appli—
provide a process for the production of 1,1,l-trichloro
cable to other chlorination reactions wherein catalysts
other than light are employed.
Suitable directive chlorination reaction mediums in
clude compounds selected from a group of organic com
ethane from 1,1-dichloroethane wherein extremely high
pounds consisting of hydrocarbons, halogenated hydro
cial usage of these processes.
Accordingly, it is an object of the present invention to ,
vyields of 1,1,1-trichloroethane are obtained without the
carbons, esters and sul?des containing up to about 20
production of large amounts of 1,1,2-trichloroethane and 25 carbon atoms, and including inorganic sul?des having up
other chlorinated products. Speci?cally, it is an object
to about 2 sulfur atoms.
of the invention to provide a process for the direct photo
Suitable directive chlorination solvents for the practice
chemical chlorination of 1,1-dichloroethane without the
of this invention include aromatic compounds, whether
formation of large amounts of by-products such as tetra
substituted or unsubstituted, for example, benzene, l-chlo
chloroethanes and higher polychlorinated ethanes which 30 'ronaphthalene, t-butyl benzene, mesitylene, o-xylene, and
generally predominate in chlorination reactions. It is also
the like. Other solvents are compounds with conjugate
an object of the present invention to provide a new and
unsaturation whether cyclic or acyclic, for example, cyclo
contiuous process for the photochemical directive chlori
pentadiene and cyclopentadienyl derivatives, 1,3-buta
ation of 1,1-dichloroethane wherein increased overall
diene, and the likejhy'drocarbon sulfur compounds, ethyl
35 sul?de, phenyl sul?de including carbon disul?de, and the
e?ciency and economy are realized.
These and other objects are achieved according to the
like. Aliphatic hydrocarbons, whether substituted or un
present invention which comprises reacting 1,1-dichloro
substituted, saturated or unsaturated, straight chain or
ethane and chlorine in a directive chlorinationreaction
branched chain, can also be employed, for example,
medium while maintaining the said reaction at a tempera"
butane, nitrornethane, methyl acetate, vinyl chloride, and
ture of from about —10° C. to about 100° C. and in the
the like. Complexing agents which can be used include
presence of actinic light. Preferably the temperature is
not only all of the foregoing classes of solvents, but also
maintained at from about 20° C. to about 60° C.
sulfuryl chloride, thionyl chloride, silicon tetrachloride,
The
reaction is generally conducted at atmospheric pressure,
and the like.
'
though positive or negative pressure can be employed.
A highly unique and highly preferred directive chlori
45
Gaseous chlorine, liquid 1,1-dichloroethane and a liquid
nation medium is a solvent consisting essentially of car
directive chlorination solvent are passed continuously
bon disul?de. This is so because of the highly directive
through a photochemical chlorination zone wherein the
chlorination effects of carbon disul?de and because it is
chlorination reaction occurs. The chlorine and 1,1-di
not chlorinated in the reaction. In addition, this particu
chloroethane are generally maintained at a ratio of chlo
lar solvent possesses many unique advantages which per~
rine:1,1-dichloroethane of from about 0.2 to about 2.0.
mit its use in a highly unique commercial operation.
Preferably the ratio of chlorine: 1,1-dichloroethane is from
The method and the manner in which the process is
about 0.8 to about 1.2. The directive chlorination solvent
carried out will be more clearly understood from the
is maintained within the chlorination reaction zone in the
following description and the accompanying schematic
proportions of from about 10 to about 70 percent based
diagram or ?oW sheet which illustrates a preferred tech
55
nique for carrying out this invention.
on the sum total Weight of the 1,1-dichloroethane and the
Referring to the ?gure, is shown a tubular type reactor
said solvent. Preferably the solvent is from about 30 to
20. Within the reactor 20 is provided an annular reaction
about 60 percent based on the sum total weight of the
zone 32 which is formed by the inner Walls 31 of the
' 1,1-dichloroethane and the solvent.
Quite suprisingly, it has-been found that a variety of
compounds have a pronounced directive chlorination ef
fect when chlorinating 1,1-dichloroethane. Thus, by
reactor 20' and the outer walls of the light well 30.
Within the light well 30 is suspended a source of actinic
light 28. Between the inner walls of the light well 30
and the outer Walls of the source of actinic light 28 is
chlorinating 1,1-dichloroethane in contact with or while
formed an annular cooling zone 29 through which refrig
dissolved in such a compound or solvent, the quantity of
erated or cooling water is circulated during the reaction.
1,1,2-trichloroethane which is ordinarily produced in most 65
Liquid 1,1-dichloroethane and directive chlorination
chlorination reactions, or in a corresponding reaction in
solvent are passed into the reaction zone 32 through line
the absence of such compounds, is greatly reduced. For
26. The entering liquids circulate downward and the 1,1
example, in the ordinary photochemical chlorination re
dichloroethane reacts with the ascending chlorine gas
action of 1,1-dichloroethane the ratio of 1,1,1-trichloro
which is passed into the reaction zone 32 through line 21.
ethane:1,1,2-trichloroethane is about 3:1. When a direc
Unreacted chlorine, and the hydrogen chloride formed
tive chlorination compound is employed in the reaction,
‘during the reaction, are removed from the reaction zone
3,01 91 75
3
4?.
?ts of the directive chlorination reaction. The following
example shows even greater bene?ts than obtained in the
32 through line 27. The solvent, liquid and liquid reac
tion products, especially 1,1,1-trichloroethane and unre
foregoing example.
acted 1,1-dichloroethane, are removed from the reactor
EXAMPLE II
20 through line 22 and passed into the distillation column
Flo‘ Thita’se plioducts are taken from the reaction 2.0116 32 5
The directive photochlorination reaction was again car- '
at a, point Shgh?y below that wherein the chlonn? gas
ried out with carbon disul?de as in the foregoing example.
farmers the reactlon Zone 32' l’l’lfmchloroethane'1S re'
The quantity of directive chlorination solvent employed
,‘Ewved from the bottom of the reacuon column 10 through
in the reaction was further increased. 0.12 part per hour
line 23 and Sent to. storage.’
of 1,1~dichloroethane and 0.18 part per hour of carbon
.Umeacted l’l'dlchlom"
‘ethane and the direct1ve chlorination solvent, where lower 10 disul?de was charged into a reaction Zone_ The Solvent
bolhng than the. l?l’litnchloroethane’ are removed from
thus constituted 60 weight percent of the sum total of sol
the top of the dlstlllatlon column 10 through. lme 24 and
vent and l’bdichloro?thane'
The charge was contacted
recycled through line 26 back into the reactor 20. Make_ with 010 part per hour of gaseous chlorine. In this in_
up quanmles of 1’1‘d1°l.11°r°ethane and Solvent are added
stance the reaction was carried out at‘ a temperature of
to the system?hroughllllé 25'
_
,
15 32° C. 0.21 part per hour of chlorinated reaction prod
The rollowmg nonlimitmg examples are illustrative _0f
mm were formed. The chlorinated products were found
the present inventlonz All parts are given in we1ght umts
to contain 94 Percent LLLmCmomethane and only 6
unless otherwise Specl?edpercent 1,1,2-trichl0roethane. This amounts to a ratio of
EXAMPLE I
20 1,1,1-trichloroethane:1,1,2-trichloroethane of 15:1. Only
.
.
0.12 part per hour of 1,1-d1chloroethane and 0.12. part
l
h
'
th
er
3138:1151 023 percent of other PC ye lormated e ams W e
per hour of carbon disul?de solvent were passed into a re-
'
EXAMPLES HLVI
action zone wherein the 1,1-dichloroethane was contacted
With 021 part per hour of Chlorine gas- The reaction Was
Referring to the table below is shown the results of
conducted in the presence of a 450 watt quartz mercury 25 several other demonstrations.
I
vapor lamp, the Spectrum Of Which ranged from 2200
(UV) to 14,000 (infrared) angstroms and having an arch
length of 4.5 inches. The temperature of the reaction‘
The procedure of Example I is repeated in all details
except for the changes shown in the table below. In these
demonstrations various solvents are employed, at varying
was maintained at 36° C.
concentrations, the reaction is conducted at various reac
.
About 60 percent of the 1,1-dichl0r0ethane entered 30 tant ratios and at varying temperatures. It has been found
into the reaction with the chlorine per pass. The reaction
that lower temperatures favor a greater formation of 1,1,1
product was found to contain 90 percent by weight 1,1,1trichloroethane in relation to the 1,1,2-trichloroethane and
trichloroethane and only about 10 percent by weight 1,1,2-
higher chlorinated products produced. Lower tempera~
'trichloroethane.
tures are therefore preferable.
This corresponds to a 1,1,1-trichloro- V
'
Table
Percent Solvent
7
Example
in 1,1‘Dichloro-
7 Solvent
, Ethane-Solvent
Feed Composition
Ratio, 1,1,1
Molar Feed
Temp. of
Triehloro
Ratio,
Reaction,
ethane:1,1,2
Chlorine:l,1Dichloroethane
° 0.
Trichloro
ethane in
,
_
Carbon tetrach1oride__-.
60,
Benzene _______________ _.
40
0.8:1
45
12.1:1
Sulfur m0nochloride_____
20
0. 7:1
£10
12:1
Phenyl sul?de ________ _-
r 37
14:1
75
17:1
ethane:1,1,2-trichloroethane ratio of 9:1. Less than 1.0 50
percent by weight of higher chlorinated ethanes were
found in the reaction product.
'
'
The following results were in sharp contrast with the
foregoing. Thus, a demonstration wasconducted wherein
71.11
Product
0 '
6.521
EXAMPLE‘ VII
Examples Ithrough VI are repeated in all details ex
cept that in these instances the directive chlorination sol
' vents employed are: methyl cyclopentadienyl, vinyl chlo
ride, n,n-dimethylformamide, chlorobenzene, toluene, o
reaction conditions were maintained the same except that 55 xylene, ethyl benzene, nitrobenz'ene, methoxy benzene, p
the directive chlorination solvent was eliminated. 0.26
trimethylsilane, anisole, p-xylene, cumene, m-xylene, t
part per hour of 1,1-dichl0roethane was reacted with 0.19
butyl benzene, mesitylene, iodobenzene, diphenyl ether,
part per hour of chlorine gas under identical conditions
diphenyl, and 1-chloronaphthalene, respectively. As in
‘except that no carbon disul?de solvent was employed in
the foregoing examples, therproductproduced in the
the reaction. The reaction products were found to con
photochlorination reaction shows an increase in the ratio
tain 75 percent by weight 1,1,1-trichloroethane and 25 per
cent by weight 1,1,2-trichloroethane. This corresponded
to a 1,1,1-trichloroethane:1,1,2-trichloroethane ratio 'of
3:1. About 5 percent by weight of higher chlorinated
ethanes, etc. was found in the product.
’ .
'
'
.
.
It is thus seen that the bene?ts obtained by the use of
the present method greatly enhances the value of the
of 1,1,1-trichloroethane: 1,1,2-trichloroethane produced.
Also, only a' small‘ fraction of other’ polychlorinated
ethanes are produced.
7
' Suitable directive chlorination reaction mediums include
compounds selected from a group of organic compounds
consisting of hydrocarbons, halogenated hydrocarbons, es
tersrand sul?des containing up to about 20 carbon atoms,
present photochemical operation. By the directive effect
and including inorganic sul?des having up to about 2
of the carbon disul?de solvent a drastic decrease in the '
sulfur atoms.
Such compounds'include aromatic com
Weight of 1,1,2-trichloroethane has resulted. Only about 70 pounds, whether substituted or unsubstituted; for example
40 weight percent of the 1,1,2-trichloroéthane which
would normally have occurred was produced in thereac~
tion. Only 20 weight percent as much higherchlorinated
products were formed.
_
'1
‘
.
The following examples further demonstrate the bene
benzene, diphenyl, t-butyl benzene, mesitylene, o-xylene
and, the like; aliphatic compounds, straight, chain or
branch chain, saturated or unsaturated, substituted or un
substituted, isobutane, heptane, nitrobutane, and the like;
cyclic compounds, substituted or unsubstituted, cyclo
3,019,175
pentadiene, methyl cyclopentadiene, cyclohexane, and the
like; halogenated hydrocarbons of any of the foregoing
classes of compounds, for example, chloroprene, benzyl
chloride, hexachlorobenzene, iodobenzene, 1,1,2,2—tetra
chloroethane, vinyl chloride, vinylidene chloride, ethylene
dibromide, l-chloronaphthalene and the like. Compounds
having conjugate unsaturation are especially preferred be
6
rine, in a ratio of chlorine:1,1-dichloroethane of from
about 0.2 to about 2.0, in a liquid hydrocarbon sul?de sol
vent, while maintaining the said reaction at a temperature
of from about 20° C. to about 60° C. and in the presence
of actinic light, and recovering a reaction product mixture
having at least about a 9:1 ratio of 1,1,1-trichloroethane:
1,1,2-trichloroethane.
cause of their highly directive chlorination effect. Esters
3. A process for the production of 1,1,1-trichloro
suitable for the practice of this invention include aromatic
ethane comprising reacting 1,1-dichloroethane and chlo
and aliphatic esters such as methyl benzoate, phenyl benzo 10 rine, in a molar ratio of chlorine:1,1-dichloroethane of
ate, methyl acetate, ethyl acetate, and the like. Sul?de
from about 0.8 to about 1.2, in a carbon disul?de solvent,
compounds include aliphatic and aromatic sul?des, for
said solvent being maintained at about 10 to about 70
example, ethyl sul?de, methyl ethyl sul?de, vinyl sul?de,
weight percent of that of the sum total weight of the re
diisoamyl sul?de, hexynyl sul?de, dibenzyl sul?de, phenyl
action solvent and the 1,1-dichloroethane, While main
sul?de, and the like; and also inorganic sul?des such as 15 taining said directive chlorinating solvent at a tempera
sulfur monobromide, sulfur monochloride, and the like.
ture of from about 20° C. to about 60° C. and in the
1,1,1-trichloroethane is useful as a solvent for the liq
presence of actinic light, and recovering a reaction prod
uid and vapor phase degreasing of metals.
uct mixture having at least about a 9:1 ratio of 1,1,1-tri
From the foregoing description and examples it is read
chloroethane: 1,1,2-trichloroethane.
ily apparent that the present invention is subject to con 20
4. A process for the production of 1,1,1~trich1oro
siderable variation without departing from the spirit and
ethane comprising reacting 1,1-dichloroethane and chlo
scope thereof.
rine, in a molar ratio of chlorine:1,1-dichloroethane of
Having described the invention, what is claimed is:
from about 0.8 to about 1.2, in carbon disul?de solvent,
1. A process for the manufacture of 1,1,l-trichloro
said solvent being maintained at about 10 to about 70
ethane comprising reacting 1,1-dichloroethane and chlo 25 weight percent of that of the sum total weight of the sol
rine in a solvent selected from the group consisting of
vent and the 1,1-dichlorocthane while maintaining said
liquid aromatic hydrocarbons, liquid hydrocarbon sul?des
solvent at a temperature of from about 20° C. to about 50°
and liquid inorganic sul?des, While maintaining the said
C., in the presence of actinic light, and recovering a re
reaction at a temperature of from about —10° C. to
action product mixture having at least about a 9:1 ratio
about 100° C. and in the presence of actinic light, and re 30 of 1,1,1-trichloroethane: 1,1,2-triehloroethane.
covering a reaction product mixture having at least about
References Cited in the ?le of this patent
a 9:1 ratio of 1,1,1-trichloroethane:1,1,2-trichloroethane.
2. A process for the manufacture of 1,1,1-trichloro
UNITED STATES PATENTS
‘ethane comprising reacting 1,1-dichloroethane and chlo
2,861,032
Scherer ______________ __ Nov. 18, 1958
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