close

Вход

Забыли?

вход по аккаунту

?

код для вставки
and?
2,410,647
raoiopoa'iorg or‘ apart. 002:
1
Walter Flemming and Gerhard Stein, Lud
haien-on-the-Rhinc, Germany, assignora, by
mesne assients, to General Aniline &
Corporation, New York, N. ‘3., a corporation of
. Delaware
No Drag. Application .l’uly e, 193s, Serial No.
2ll7,'i‘i9._ in Germany July 29, 193':
i
_
'
a claims"? (cl. 260-654)
The present invention relates to the production
of allyl chloride.
propane or propyl chloride serving as initial ma
terial are ‘preferably so chosen. that the chlorine
We have found that allyl chloride can be ob
tained in a very advantageous manner by causing
is present in a smaller amount than corresponds
to the theoretical amount. For example it is
chlorineto react with an excess of propane or
advantageous to use a proportion of from about
propylchlorlde alone or in admixture with each ' - 2 to 3 molecular proportions of propane to 1 mo
other or with propylene at temperatures between
about 500° and about 700° C., and causing the
lecular proportion of chlorine or 3 molecular pro
reaction to proceed with the aid of metallic con
tact catalysts which are indifferent to the action 10
of hydrogen chloride.
Any propylchloride formed in addition to allyl
chloride or remaining unchanged in the said
portions of propyl chloride to'l molecular pro-\
portionof chlorine.
.
'
It is advantageous‘ to introduce the chlorine
and the propane or propyl chloride to be reacted
separatelyinto the reaction chamber and to mix
them a short distance in front of the catalyst.
process may subsequently be converted into allyl
This may readily be effected through suitable
nozzles. The starting materials ‘may separately
be preheated before the reaction, or it may be
to the said treatment or splitting o? hydrogen
su?icient to preheat propane or propyl chloride
therefrom by treatment with agents binding hy
alone and to then admix them with cold chlorine.‘
drogen at high temperatures, whereby, contrary
The temperature should be sochosen that the
to expectation, the halogen remains in the mole 20 mixture is preheated to at least 150° C. Thepre
cule.
'
heated mixture is now led with high speed of flow
chloride by the removal of hydrogen. This may .'
- be e?ected'for example by subjecting them again
When the said reaction is carried out at com
into the reaction chamber, in which the metal
paratively low speeds of ?ow, it may happen that
catalyst is situated. The catalyst is heated, be
fore starting the reaction to at least 350° 0., ad
vantageously to reaction temperature between
an undesirable reaction between the reactants
takes place in the gas mixture before the catalyst 25
zone is reached; the reaction then takes place
500° and about 700° C. The reaction commences somewhat in the same way as a ?ame striking
after' a. short time and it remains limited to a
back, strong formation of carbon black thus tak
‘small zone of the catalyst which is continuously
ing place. The speed of-?ow must therefore al
heated to redheat by the reaction heat formed.
ways be relatively high and, indeed, higher than 30 Further external heating should then be dis
the speed of ?ame propagation. The reaction
continued. When workingwith a high through
then takes place in the desired manner only after .
put, it may even be necessary to conduct the heat
reaching the front part of the catalystor in a
formed away by cooling in order to avoid-a too
relatively small zone situated on the catalyst or
far reaching heating.
at its end.
~
As catalysts there are used metals or mixtures
of metals or alloys which undergo no reaction or
no appreciable reaction with hydrogen chloride,
as for example chromium-nickel or chromium
nickel-iron alloys, platinum, rhodium, silver,
tungsten, tantalum, niobium, osmium, and alloys
35
It is usual to work at normal pressure, but it is ' I
possible to carry out the reaction at reduced ‘or
increased pressure. Diluent inert gases, such as
nitrogen may also be used. The reaction gases
obtained are cooled after leaving the reaction
40 chamber, whereby a part of the allyl chloride
of the same with each-other or with other me
formed separates; the part which does not sep
arate is separated from the hydrogen chloride
tallic constituents.
formed, preferably with water in washing towers.
The catalysts are preferably ‘
used in the form of netting, rolled-up netting. ‘ dried and separated by strong cooling or com
spirals, threads, granules, balls or cuttings. 45 pression.
Shaped carrier material may also be provided
_ The following examples will further illustrate. ‘
with a coating of good thermal conductivity of
how our present invention may be carried out in
metals or metal alloys suitable as catalysts;
practice but the invention is not restricted .to.
these examples.
~
Their resistance to chemical attack may advan
tageously be increased by a thin coating or gra 50
'
Example 1
phitic carbon (lustrous black carb'on) which may
A rolled-together chromium-nickel wire net-q
be produced on the surface of the catalyst for'
ting is charged into the rear part of atube of
example by burning in a- coating of brown coal
V2A-steel (a corrosion-resistant steel containing
tar.
from 15 to 20 per cent of chromium, from 5 to 9
The mixing proportions of chlorine and the
per cent of nickel and from 0.1 to 0.3 per cent-o!
c circles? V
worked up in'the
car-Mn). in e trout portion or the tube. chlo
rice is led by means of a narrow tube provided
with save
a openings. Over ‘this chlorine in
let tube there ?
propane in such an amount
that a
are is formed which contains proe'
r described above. The
Y condensate obtained contains 15 per cent of allyl
chloride, 15 per cent oi’ propyl chloride and 10
per cent of higher chlotion products.
‘What we claim is:
_
‘
1. The process of producing allyl chloride
4 and chlorine in the molccr proportion of 3:1.
' which comprises causing a
The propane is preheated to 206° E. and the cat=
ular proportion of chic
alyst is at first heated externally to 400". C. "In i- on
use of one molec=
to react in the gas
phase with at least two molecular proportions of
the mixture of propane and chlorine meets ‘the
a‘ compound selected from the group co sir-fits
of propane and propyl chloride at a
perature
' catalyst, ignition takes place and there is formed
in the front part of the catalyst a small glow
ing zone of from about i to 2 centimeters depth :_ ' between about 500'’
about ‘200° C'.,-while pass
- ingthe gas mixture through a reaction space
which has a temperature of 600° C. By main
charged with a metal selected from the class. con
taining a relatively high speed of ?ow of the mix
ture or propane and chlorine, care is taken that 15 slsting of chromium-nickel alloys and chromium
nickel-iron alloys which are stable to the action
the glo
cone remains continually in the front
of hydrogen chloride, said metal being arranged
part of the catalyst. By regulating the preheat
within the reaction space so as to present a large
ing oi the reactants and the heating specially
surface area to the gas mixture, and separating
supplied to’ the catalyst as well as by regulating
the do
and mixing proportions, it is possible 20 allyl chloride from the reaction gases formed.
2. The process of producing allyl chloride
to regulate the temperature of the glowing zone.
which comprises causing a, mixture of one molec
The mixture leaving the reaction chamber is ;'
ular proportion of chlorine‘ with at least two
molecular proportions of a compound selected
from the class consisting of propane and propyl
chloride, which mixture is preheated to tem
cooled. washed, driedand condensed. There is
' formed in a very good yield a reaction product
which contains 32 per cent of_ allyl chloride, 59 -
per cent of propyl chloride, 7.6 per cent of propyl
peratures above 150° C. but below reaction tem
perature, to react at a temperature between about
ene chloride and 1.2 per cent of higher chlorina
tion products. Since the mixture leaving the re
7 500°
action chamber, after removing the hydrogen ~
about 700°C. while I e s“
the gas mix
chloride and adding further amounts 0! chlorine, 3D ture through a reaction space ‘charged with a
metal selected from the class consisting of chro
mium-niclrel alloys and chromi-nickel-iron
alloys which are stable to the action of hydrogen
is led over the same ,or a similar catalyst under
about the said conditions, the fraction of allyl a
chloride can be still further considerably in
creased.
_
r
4
Example 2 .
chloride, said metal being arranged within the I
35 reaction space so as to present a large surface
A mixture containing 35 per cent of propane
and 65 per cent of propylene is substituted for '
the propane in the manner oi working described
area. to the gas mixture, and separating allyl
,_ chloride from therea'ction gases formed.
3. The process of producing allyl chloride
“which comprises causing one molecular propor
1 in Example 1. /The catalyst in this case is ?rst " tion of chlorine to react in the gas phase with
40
heated only to 350° C. Ignition immediately
takes place atlthe catalyst and asmall glowing‘
zone is formed within the catalyst which has a
temperature oi’ about 600° C. ‘ By regulating the
at least two molecular proportions oi’ propane at
a temperature between about 500° and about 700°
C., while passing the gas mixture through a re
action space charged with a chromium-nickel
heat specially supplied, the temperature of the 45 alloy which is stable to the reaction of hydrogen
glowing zone is regulated to 630° C. The mix
chloride and is arranged within the reaction space
ture leaving the reaction chamber is cooled,
so as to present a large surface area to the gas
washed, dried and condensed by strong cooling
to 20° below zero 0., the unchanged residual gas
being returned in circulation. The condensate
contains 58 per cent of allyl chloride, 2'4 per cent
of propyl chloride and about 18 per cent of higher
chlorination products.
Example 3
A mixture consisting of 1 molecular proportion '
' oi’ propyl chloride and 2' molecular proportions
oi’ propylene is heated to 250° 0., and then led
together with 1 molecular proportion of chlorine
mixture, and separating allyl chloridefrom the
reaction gases formed.
I
4. The process of producing allyl chlorid
which comprises causing one molecular propor
tion of chlorine to react in the gas phase with at
least two molecular proportions of propyl chloride
at a, temperature between about 500° and about -
700° 0., while passing the gas mixture through a
reaction space charged with a. chromium-nickel
alloy which is stable to the reaction of hydrogen
chloride and is arranged within the reaction
space so as to present a large surface area to the
through a tube as described in Example '1. The '7
catalyst was preheated to about 360° C. Ignition 60 gas mixture. and separating'allyl chloride from’
the reaction gases formed.
takes place at the catalyst, and a small glowing
aone is formed therewithin which has a tempera
ture of about 610° C. The reaction gases are
-
1
-
WALTER FLEM'MING.
GERHARD STEIN. }
Документ
Категория
Без категории
Просмотров
0
Размер файла
345 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа