Improvements in Processes of and Apparatus for Making Pure Aceton.
Year: 1895

page_text: Date of Application, 12th Mar., 1899
Complete Specification Left. 12th Dec., 1895-Accepted. 12th Mar.. 1896
Date v Application, 1201 Mar., 1899
Complete Specification Left. 12th Dec., 1895-Accepted. 12th Mar.. 1896
PROVISIONAL SPECIFICATION.
Improvements in Processes of and Apparatus for Making Pure
Aceton.
I, OTTOKAR PORSCH residing in Orangeburgh, in the County of Orange and
State of New York, United States of America Chemist, do hereby declare the
nature of this invention to be as follows:-
In the manufacture of smokeless powder chemically pure aceton is required
which for the purpose of meeting the requirements must have the following
characteristics :-
Firstly it must be perfectly clear and limpid.
Secondly it must be miscible with distilled water in every proportion and the
mixture should not show a cloudiness or a precipitate either directly after mixing or
after considerable standing; thirdly it must be perfectly neutral; fourthly it must
indicate at a temperature of 15° Celsius on a thermo-alcoholometer of Schultze
(Berlin) at least 99.5 per cent.; fifthly the aceton should not contain more
than 0.1 per cent. of aldehyde and its iodemetric test should not indicate less than
98.5 per cent. of C'HO; sixthly in distilling the aceton, at least 98.8 per cent. of
the liquid should have passed over when the thermometer indicates 58° Celsius.
My invention is designed for producing aceton having the foregoing character-
istics and it consists of a process of making pure aceton by subjecting an acetate in
the presence of calcium-hydrate in excess at a uniform temperature to destructive
distillation and to the action of super-heated steam. The aceton-vapeurs thus
obtained are next condensed into crude liquid aceton which is mixed with water in
excess and permitted to stand so as to separate the aceton from the water and
tar-oils the clear water-containing aceton being finally subjected to fractional
distillation and rectification. The invention consists further of an apparatus for
making aceton which comprises a jacketed mixing vessel or retort having closed
supply and discharge openings rotary scrapers in said retort a perforated steam
supply-pipe a collecting vessel provided with a heating coil a pipe connecting the
mixing vessel with the collecting vessel a condenser a pipe-connecting the collecting
vessel with the condenser, and steam pipes arranged axially in line with the
connecting pipes so as to permit the quick removal of the dust settling in
the same.
The mixing vessel or retort is connected with the collecting vessel by a pipe and
the collecting vessel with the condenser by a pipe. The bottom of the mixing vessel
is formed of an interior and an exterior section the space between which is entirely
filled with molten lead. The circumferential flange of the top or cover and the
circumferential flanges of the outer and inner sections of the mixing vessel are
firmly connected by screw bolts or in other suitable manner. The lead is run in
molten condition into the space formed by the double-walled body and is retained
in molten condition in the same by the heat of a suitable furnace which is built
around the mixing vessel.
Suitable openings are provided in the flange of the cover and intermediate ring
for supplying the lead said openings being closed by means of plugs. The cover is
provided at its centre with a stuffing box which forms a bearing for a vertical shaft
that extends in downward direction through the mixing vessel said shaft being
supported at its lower end by an interior step-bearing at the bottom of the interior
section of the mixing vessel and by an exterior neck bearing. A man-hole is

page_text: arranged in the cover of the mixing vessel and closed by a man-hole cover in the
usual manner said man-hole being used for charging the mixing vessel while a
discharge opening is arranged in the lower part of the interior and exterior.
د
The collecting vessel connecting pipe is composed of three sections that are
arranged at right angles to each other the sections diminishing gradually in
diameter. The rectangular pipe sections are extended beyond their intersections
and are closed at their ends with detachable covers through which steam pipes
provided with stop-cocks pass to the interior of the pipe sections said steam pipes
being in line with the axes of said pipes so as to permit the convenient cleaning of
the sections of the connecting-pipe from the dust deposited in the same. In the
horizontal section of this connecting pipe is arranged a damper provided with a
handle so that the pipe can be closed for facilitating the cleaning of the sections
at either side of the damper. This connecting pipe extends downward into the dust
collecting vessel and is obliquely cut off at its lower end so as to deliver the aceton
vapours into the collecting vessel.
A dust collecting vessel is provided at its lower part with a heating coil to
which steam is supplied and which is provided with a valved steam inlet and outlet
pipe.
It is further provided with a man-hole and man-hole cover at its lower part for
removing the accumulated dust and permitting the cleaning of the dust collecting
"essel.
The pipe by which the dust-collector is connected with the condenser (which I
11 term the condenser connecting pipe) is provided with a dust catcher formed of
inclined conical tubes and a closed bottom said dust catcher being arranged below
the outlet opening in the top of the collector so as to retain the dust as much as
possible in the collecting vessel and prevent its passage with the vapours to the
condenser.
All the parts heretofore described namely the mixing vessel the dust collecting
vessel and its connecting pipe may be made of cast iron while the condenser and its
connecting pipe between the collecting vessel and the condenser are advantageously
made of copper.
The condenser is constructed on the counter-current principle cold water beg
supplied to the bottom of the same while the warm water is discharged at the upper
part of the same. A number of cooling tubes are arranged in the condenser
through which the vapours are conducted while the water passes over a number of
horizontal trays that extend alternately from one side of the condenser towards the
other side. The crude liquid aceton is discharged through a bottom pipe into a
collecting vessel while the carbonic acid is conducted off through a vertical pipe
that communicates from the bottom pipe into the atmosphere.
The condenser connecting pipe is (like the collecting vessel connecting pipe)
formed of sections that are arranged at right angles to each other each section being
extended beyond its intersection with its adjacent section and provided with a
detachable cover through which extends a steam pipe provided with a stop cock
said steam pipe serving to admit steam to the interior of the pipe for removing the
dust settled in the same the dust in the sections of this connecting pipe being forced
into the dust collecting-vessel and through its man-hole to the outside while the
dust in the sections of other connecting pipe is forced into the mixing vessel and
through the discharge opening of the same to the outside. By this arrangement the
entire apparatus can be cleaned of the dust settled in the connecting pipes in a very
short time so that the time heretofore taken up for cleaning the different parts of
aceton-distilling apparatus is saved and the annoyance caused thereby to the
attendants dispensed with.
In producing the aceton a suitable acetate advantageously the commercial acetate
of lime is mixed with calcium hydrate and charged into the mixing vessel or
retort.
Each charge may consist of any quantity (say about 600 pounds) from which the
aceton is distilled off in about four hours including the time required for charging

page_text: and discharging the mixing vessel. The charging of the apparatus is accomplished
in about five minutes and the discharging takes up about the same time.
The charge has to be subjected to uniform heat in the mixing vessel which is
accomplished by means of the lead bath in which the lead is retained in liquid
condition by the heat of the furnace. It is advantageous to employ petroleum for
heating the mixing vessel the heating device being of any approved construction
advantageously in the nature of a suitable hydro-carbon vapourizer to which the
hydro-carbon is supplied by a pipe while air under pressure is conducted through a
pipe both these pipes being provided with suitable stop-cocks so as to produce the
proper supply of oil and air respectively. By heating the apparatus with petroleum
a quicker heating up of the apparatus and a more uniform heating of the same can
be obtained than with ordinary fuel. The lead bath serves for the purpose of
keeping the temperature of the mixing vessel perfectly constant during the
generation of the aceton-vapours so that any chance of decomposing the aceton
is obviated.
Before introducing the molten lead in the space between the interior an 1 exterior
sections of the mixing vessel the exterior section is first heated to a light red heat
so that the lead remains in liquid condition and that the interior of the mixing
vessel assumes a temperature equal to the melting point of the lead and is thereby
ready for the introduction of the acetate. The heatel charge of acetate of lime
and calcium hydrate is introduced through the man-hole in the cover which is then
closed quickly as the generation of aceton commences instantly upon the charging
of the mixing vessel. The scrapers are then set in motion so that the acetate of
lime is subjected under continuous stirring to heat in the mixing vessel. The
aceton vapours pass through the connecting-tube into the collecting vessel and
thence to the condenser. When about 12 to 15 per cent. of the aceton contained
in the charge has passed over the charge becomes perfectly dry and assumes a dust-
like shape so that it is necessary to supply super-heated steam into the mixing
vessel. The supply of steam is kept up until the end of the operation. The aceton
vapours are condensed in the condenser the crude liquid aceton being con lucted to
a suitable receiver. As soon as water commences to be discharged through the
discharge pipes the operation is completed and the contents of the mixing vessel
can be discharged which is accomplished by opening the cover of the discharge
opening. The scrapers then move gradually the entire body of carbonate of lime
towards the discharge opening and through the same to the outside so that the
mixing vessel is in condition to be immediately charged again with a dry mixture
of acetate of lime and calcium-hydrate in excess as before described.
The thus obtained crude aceton-that is to say the quantity of aceton which
results from a suitable working period say twenty-four hours-is next mixed with
about ten times its weight of water and allowed to stand for twenty-four hours in
closed vats at a cool place. The vats are provided with a water-gauge and with
four discharge faucets located at different heights so to decant on the one hand any
tar-oils that collect on the surface of the solution and draw off on the other hand a
clear mixture of aceton and water from the sediment collected at the bottom of
the vats.
The clear water containing aceton is next transferred to a dephlegmator and
subjected in the same to fractional distillation. The initial and final runs of about
fifty pounds each are set aside while the quantity that runs off between t'e initial
and terminal runs and which is a distillate containing about from 90 to 96 per cent.
of aceton is separately treated so as to permit the removal even of the small
percentage of water still contained in the same.
This is accomplished by a final distillation of the aceton which is produced in a
column rectificator constructed in the following manner :—
On a copper still is supported a rectifying column composed of a large number of
trays which column is connected with two condensation-cylinders to the lower
cylinder of which the cooling water is supplied at a temperature not below 15° C.
The cooling water after being heated to 25° C. is conducted to the lower part of

page_text: the upper condensation cylinder the temperature of the cooling water being so
regulated that the water passing from the upper condensation cylinder should
neither rise above 58° C. the boiling point of pure aceton nor pass off at a
temperature below 50° C.
The rectification of the aceton is so regulated that not more than 150 litres should
pass over per hour but even of this distillate the first 50 litres and the last 50 litres
should he set aside as containing perhaps some traces of aldehyde. When the
iodometric test shows that the quantity of the aceton which has been set aside
being a certain quantity running over at the beginning and at the end of one
distillation mixed with the same quantity obtained by a second distillation should
contain more than 0.1° of aldehyde then the aceton is passed in gas form through
tubes that are heated to red heat and then condensed again so that the ketones that
boil at a higher temperature than the aceton are split up. The so-treated initial
and final runs of the distillation are mixed with the next quantity of aceton and
subjected to rectification whereby it is possible to obtain the greatest possible
yield of chemically pure aceton which yield approaches very closely the theoretical
yield.
The advantages of my improved process of obtaining pure aceton consists in the
following facts :-
First by adding an excess of calcium hydrate to the acetate of lime employed
every atom of acetate acid is liberated and an alkaline residue of carbonate of lime
obtained that is perfectly free from acetic acid so that the yield of aceton
approaches almost the limit of the theoretical yield and thereby 25 per cent. of
pure aceton boiling at 58° C. be regularly obtained from ordinary commercial
acetate of lime.
Second By the use of a lead bath having a constant melting point the super-
heating of the interior of the mixing vessel is obviated and any variations to
temperature during the generation of the aceton from the charge prevented
whereby an aceton is obtained which is free from decomposition products such as
aldehyde and ketones.
:-
Third By the introduction of superheated steam into the mixing vessel after
about 12 per cent. of the aceton has gone over the generation of the remaining
aceton is accelerated while the formation of mechanical impurities and the passing
over of any portion of the charge in powder form from which the aceton has not
been separated is prevented.
Fourth-The connecting tubes between the mixing vessel and the dust collecting
vessel and between the latter and the condenser can be readily cleaned after each
operation by the steam-supply pipes so that the choking of the tubes by the settling
of dust-particles and the occurrence of explosions arising from the same can be
entirely prevented.
Fifth By supplying superheated steam to the collecting-vessel the free and
uniform passage of the aceton vapours into the condenser is accomplished and
thereby the formation of mechanical impurities and the choking of the condensing
coil with dust particles prevented.
Sixth-By mixing the crude aceton with water and subjecting the same
afterwards to fractional distillation it is possible to remove every trace of tar-oil
from the aceton.
Seventh-By the use of a column-rectifying apparatus anhydrous aceton of a
high degree of purity is obtained such as is required in the manufacture of smokeless
powder for dissolving the pyroxilin.
Eighth-That any ketones which are contained in the aceton and which have a
bigher boiling temperature are split up by distillation over tubes heated to red heat
and thereby removed from the aceton.
Dated this 19th dor of March 1905

page_text: Improvements in Processes of and Apparatus for Making Pure
Aceton.
I, OTTOKAR PORSCH residing in Orangeburgh in the County of Orange and
State of New York, U.S.A. Chemist, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
In the manufacture of smokeless powder chemically pure aceton is required
which for the purpose of meeting the requirements must have the following
characteristics ;-
Firstly it must be perfectly clear and limpid.
Secondly it must be miscible with distilled water in every proportion and the
mixture should not show a cloudiness or a precipitate either directly after mixing
or after considerable standing.
Thirdly it must be perfectly neutral.
Fourthly it must indicate at a temperature of 15° Celsius on a thermo-alcoholo
meter of Schultze (Berlin) at least 99-5 per cent.
Fifthly the aceton should not contain more than 0.1 per cent. of aldehyde and
its iodometric test should not indicate less than 98.5 per cent. of C³HO.
Sixthly in distilling the aceton at least 98.8 per cent. of the liquid should have
passed over when the thermometer indicates 58° Celsius.
My invention is designed for producing aceton having the foregoing
characteristics and it consists of a process of making pure aceton by subjecting
an acetate in the presence of calcium-hydrate in excess at a uniform temperature
to destructive distillation and to the action of superheated steam. The aceton
vapours thus obtained are next condensed into crude liquid aceton which is mixed
with water in excess and permitted to stand so as to separate the aceton from the
water and tar-oils the clear water containing aceton being finally subjected to
fractional distillation and rectification. The invention consists further of an
apparatus for making aceton which comprises a jacketed mixing vessel or retort
having closed supply and discharge openings rotary scrapers in said retort a
perforated steam supply pipe a collecting vessel provided with a heating coil a
pipe connecting the mixing vessel with the collecting vessel a condenser a pipe
connecting the collecting vessel with the condenser and steam pipes arranged
axially in line with the connecting pipes so as to permit the quick removal of the
dust settling in the same.
In the accompanying drawings ;-
Fig. 1 represents a side elevation of my improved apparatus for making
aceton, and
Fig. 2 is a vertical central section through the mixing vessel or retort drawn on
a larger scale.
Similar letters of reference indicate corresponding parts.
Referring to the drawings;
A represents the closed mixing vessel or retort, B the furnace in which the
same is set for being heated, C the dust collecting vessel and E the condenser.
The mixing vessel or retort A is conuected with the collecting vessel C by a
pipe C and the collecting vessel with the condenser E by a pipe D. The
bottom of the mixing vessel A is formed of an interior and an exterior section the
space between which is entirely filled with molten lead. The circumferential
flange of the top or cover A' and the circumferential flanges of the outer and
inner sections of the mixing vessel are firmly connected by screw bolts a' or in

page_text: other suitable manner. The lead is run in molten condition into the space formed
by the double-walled body and is retained in molten condition in the same by the
heat of a suitable furnace B which is built around the mixing vessel A.
Suitable openings are provided in the flange of the cover and intermediate
ring a for supplying the lead said openings being closed by means of plugs a².
The cover A is provided at its centre with a stuffing box which forms a bearing
for a vertical shaft S that extends in downward direction through the mixing
vessel said shaft being supported at its lower end by an interior step bearing b
at the bottom of the interior section of the mixing vessel A. and by an exterior neck
bearing. A man-hole a³ is arranged in the cover A' of the mixing vessel and
closed by a man-hole cover at in the usual manner said man-hole being used for
charging the mixing vessel while a discharge opening as is arranged in the lower
part of the interior and exterior.
The collecting vessel connecting pipe C₁ is composed of three sections that
are arranged at right angles to each other the sections diminishing gradually in
diameter.
The rectangular pipe sections are extended beyond their intersections and are
closed at their ends with detachable covers through which steam pipes p¹ provided
with stop cocks p² pass to the interior of the pipe sections said steam pipes
heing in line with the axes of said pipes s as to permit the convenient
cleaning of the sections of the connecting pipe C' from the dust deposited in the
same.
. In the horizontal section of this connecting pipe C' is arranged a damper d
provided with a handle d' so that the pipe C can be closed for facilitating the
cleaning of the sections at either side of the damper. This connecting pipe C¹
extends downward into the dust collecting vessel C and is obliquely cut off at its
lower end so as to deliver the aceton vapours into the collecting vessel. A dust-
collecting vessel C is provided at its lower part with a heating coil C² to which
steam is supplied and which is provided with a valved steam inlet and outlet
pipes p³p. It is further provided with a man-hole and man-hole cover at its
lower part for removing the accumulated dust and permitting the cleaning of the
dust collecting vessel. The pipe D by which the dust-collector C is connected
with the condenser E (which I will term the condenser connecting pipe) is
provided with a dust-catcher D' formed of inclined conical tubes and a closed
bottom said dust-catcher being arranged below the outlet-opening in the top of the
collector so as to retain the dust as much as possible in the collecting vessel and
prevent its passage with the vapours to the condenser.
All the parts heretofore described namely the mixing vessel A. the dust
collecting vessel C and its connecting pipe C may be made of cast iron while
the condenser E and its connecting pipe D between the collecting vessel and the
condenser are advantageously made of copper.
The condenser E is constructed on the counter current principle cold water being
supplied to the bottom of the same while the warm water is discharged at the
upper part of the same. A number of cooling tubes are arranged in the condenser
through which the vapours are conducted while the water passes over a number
of horizontal trays that extend alternately from one side of the condenser
towards the other side. The crude liquid aceton is discharged through a bottom
pipe into a collecting vessel F while the carbonic acid is conducted off
through a vertical pipe that communicates from the bottom pipe f into the
atmosphere.
The condenser connecting pipe D is (like the collecting vessel connecting
pipe C¹) formed of sections that are arranged at right angles to each other each
section being extended beyond its intersection with its adjacent section and
provided with a detachable cover through which extends a steam pipe p³ provided
with a stop cock said steam pipe serving to admit steam to the interior of the
pipe for removing the dust settled in the same the dust in the sections of this
connecting pipe D being forced into the dust collecting vessel and through its

page_text: man-hole to the outside while the dust in the sections of other connecting pipe CI
is forced into the mixing vessel and through the discharge opening of the same to
the outside. By this arrangement the entire apparatus can be cleaned of the
dust settled in the connecting pipes in a very short time so that the time
heretofore taken up for cleaning the different parts of aceton distilling
apparatus is saved and the annoyance caused thereby to the attendants dispensed
with.
In producing the aceton a suitable acetate advantageously the commercial
acetate of lime is mixed with calcium hydrate and charged into the mixing vessel
or retort A.
Each charge may consist of any quantity (say about 600 pounds) from which
the aceton is distilled off in about four hours including the time required for
charging and discharging the mixing vessel. The charging of the apparatus is
accomplished in about five minutes and the discharging takes up about the same
time.
The charge has to be subjected to uniform heat in the mixing vessel which is
accomplished by means of the lead bath in which the lead is retained in liquid
condition by the heat of the furnace B. It is advantageous to employ petroleum
for heating the mixing vessel the heating device being of any approved
construction advantageously in the nature of a suitable hydro-carbon vapourizer H
to which the hydro-carbon is supplied by a pipe h while air under pressure is
conducted through a pipe both these pipes h h being provided with suitable
stop cocks so as to produce the proper supply of oil and air respectively. By
heating the apparatus with petroleum a quicker heating up of the apparatus and
a more uniform heating of the same can be obtained than with ordinary fuel.
The lead-bath serves for the purpose of keeping the temperature of the mixing
vessel perfectly constant during the generation of the aceton vapours so that any
chance of decomposing the aceton is obviated.
Before introducing the molten lead in the space between the interior and
exterior sections of the mixing vessel the exterior section is first heated to a light
red heat so that the lead remains in liquid condition and that the interior of the
mixing vessel assumes a temperature equal to the melting point of the lead and
is thereby ready for the introduction of the acetate. The heated charge of
acetate of lime and calcium hydrate is introduced through the man-hole in the
cover which is then closed quickly as the generation of aceton cominences instantly
upon the charging of the mixing vessel. The scrapers are then set in motion so
that the acetate of lime is subjected under continuous stirring to heat in the mixing
vessel. The aceton vapours pass through the connecting tube C into the
collecting vessel C and thence to the condenser E.
When about 12 to 15 per cent. of the aceton contained in the charge has passed
over the charge becomes perfectly dry and assumes a dust-like shape so that it is
necessary to supply super-heated steam into the mixing vessel A.
The supply of steam is kept up until the end of the operation.
The aceton vapours are condensed in the condenser the crude liquid aceton
being conducted to a suitable receiver.
As soon as water commences to be discharged through the discharge pipe the
operation is completed and the contents of the mixing vessel can be discharged
which is accomplished by opening the cover A' of the discharge opening a.
The scrapers then move gradually the entire body of carbonate of lime towards
the discharge opening and through the same to the outside so that the mixing
vessel is in condition to be immediately charged again with a dry mixture of
acetate of lime and calcium-hydrate in excess as before described.
The thus-obtained crude aceton-that is to say the quantity of aceton which
results from a suitable working period say twenty-four hours-is next mixed with
about ten times its weight of water and allowed to stand for twenty-four hours in
closed vats at a cool place. The vats are provided with a water gauge and with
four discharge faucets located at different heights so as to decant on the one hand

page_text: any tar oils that collect on the surface of the solution and draw off on the other
hand a clear mixture of aceton and water from the sediment collected at the
bottom of the vats.
The clear water-containing aceton is next transferred to a dephlegmator and
subjected in the same to fractional distillation. The initial and final runs of about
fifty pounds each are set aside while the quantity that runs off between the initial
and terminal runs and which is a distillate containing about from 90 to 96 per cent. of
aceton is separately treated so as to permit the removal even of the small
percentage of water still contained in the same.
This is accomplished by a final distillation of the aceton which is produced in a
column-rectificator constructed in the following manner;--
On a copper still is supported a rectifying column composed of a large number
of trays which column is connected with two condensation cylinders to the lower
cylinder of which the cooling water is supplied at a temperature not below 15° C.
The cooling water after being heated to 25° C. is conducted to the lower part of
the upper condensation cylinder the temperature of the cooling water being so
regulated that the water passing from the upper condensation cylinder should
neither rise above 58° C. the boiling point of pure aceton nor pass off at a
temperature below 50° C. The rectification of the aceton is so regulated that
not more than 150 litres should pass over per hour but even of this distillate
the first 50 litres and the last 50 litres should be set aside as containing perhaps
some traces of aldehyde. When the iodometric test shows that the quantity of
the aceton which has been set aside being a certain quantity running over at the
beginning and at the end of one distillation mixed with the same quantity
obtained by a second distillation should contain more than 0.1% of aldehyde
then the aceton is passed in gas form through tubes that are heated to red heat
and then condensed again so that the ketones that boil at a higher temperature
than the aceton are split up.
The so-treated initial and final runs of the distillation are mixed with the next
quantity of aceton and subjected to rectification whereby it is possible to obtain
the greatest possible yield of chemically pure aceton which yield approaches very
closely the theoretical yield.
The advantages of my improved process of obtaining pure aceton consists in the
following facts;-
First, by adding an excess of calcium hydrate to the acetate of lime employed
every atom of acetic acid is liberated and an alkaline residue of carbonate of
lime obtained that is perfectly free from acetic acid so that the yield of aceton
approaches almost the limit of the theoretical yield and thereby 25 per cent. of
pure aceton boiling at 58° C. be regularly obtained from ordinary commercial
acetate of lime.
Second, by the use of a lead bath having a constant melting point the super-
heating of the interior of the mixing vessel is obviated and any variations of
temperature during the generation of the aceton from the charge prevented whereby
an aceton is obtained which is free from decomposition products such as aldehyde
and ketones.
Third, by the introduction of superheated steam into the mixing vessel after
about 12 per cent. of the aceton has gone over the generation of the remaining
aceton is accelerated while the formation of mechanical impurities and the
passing over of any portion of the charge in powder form from which the aceton
has not been separated is prevented.
Fourth, the connecting tubes between the mixing vessel and the dust-collecting
vessel and between the latter and the condenser can be readily cleaned after each
operation by the steam-supply pipes so that the choking of the tubes by the
settling of dust particles and the occurrence of explosions arising from the same
can be entirely prevented.
Fifth, by supplying superheated steam to the collecting vessel the free and
uniform passage of the aceton vapours into the condenser is accomplished and

page_text: thereby the formation of mechanical impurities and the choking of the condensing
coil with dust particles prevented.
Sixth, by mixing the crude aceton with water and subjecting the same afterwards
to fractional distillation it is possible to remove every trace of tar oil from the
aceton.
Seventh, by the use of a column rectifying apparatus anhydrous aceton of a
high degree of purity is obtained such as is required in the manufacture of
smokeless powder for dissolving the pyroxilin.
Eighth, that any ketones which are contained in the aceton and which have a
higher boiling temperature are split up by distillation over tubes heated to red
heat and thereby removed from the aceton.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. The process herein described of producing chemically pure aceton which
consists in subjecting an acetate in the presence of calcium-hydrate in excess to
destructive distillation and to the action of superheated steam substantially as set
forth.
2. The process herein described of producing chemically pure aceton which
consists in subjecting an acetate at a uniform temperature in the presence of
calcium-hydrate in excess and under continuous agitation to distillation and to the
action of superheated steam so as to separate the aceton vapours from the
remaining carbonated lime substantially as set forth.
3. The process herein described of producing chemically pure aceton which
consists of the following steps; first mixing ordinary commercial acetate of lime
with calcium-hydrate in excess, second subjecting the mixture under continuous
stirring at a uniform temperature to the action of superheated steam so as to
separate the aceton-vapours from the remaining carbonate of lime, third
condensing said vapours into crude liquid aceton, and lastly purifying the crude
liquid aceton by subjecting it to fractional distillation and rectification
substantially as set forth.
4. The process herein-described of producing chemically pure aceton which
consists of the following successive steps first mixing the ordinary commercial
acetate of lime with calcium-hydrate in excess, second subjecting the mixture
under continuous stirring at a uniform temperature to the action of superheated
steam so as to separate the vapours of aceton from the remaining carbonate of
lime, third condensing the aceton vapours into crude liquid acetou, fourth mixing
the crude aceton with water and permitting it to stand so as to separate it from
the tar oils and sediments, fifth subjecting the purified aceton to fractional
distillation and finally rectifying the same substantially as set forth.
5. The process herein described of producing chemically pure aceton which
consists in subjecting a mixture of commercial acetate of lime and calcium-hydrate
to heat under continuous stirring supplying superheated steam to the charge so as
to facilitate the generation of the aceton vapours condensing the vapours mixing
the crude liquid aceton with water in excess so as to produce the separation of
the tar oils and sediments subjecting the washed aceton to fractional distillation
and rectification and separating the higher boiling ketones contained in the
rectified aceton by subjecting the same in gas form to surfaces heated to red heat
so as to break up the ketones substantially as set forth.
6. An apparatus for making aceton consisting of a mixing vessel or retort
provided with interior rotary scrapers a furnace for heating said mixing vessel
a dust-collecting vessel provided with a heating coil a connecting pipe between
the mixing vessel and the dust-collector a condenser a connecting pipe between
the dust-collector and condenser and a discharge pipe and receiver for the crude
aceton below the condenser substantially as set forth.
7. In an apparatus for making aceton a mixing vessel or retort composed of a
B

page_text: double-walled body filled with molten lead a cover attached hermetically to the
double-walled body and provided with a charging man-hole a discharge opening
at the bottom of the body rotary scrapers at the interior of the vessel and a steam
supply pipe provided with openings at the inside of the mixing vessel substantially
as set forth.
8. In an apparatas for making aceton the combination of a mixing vessel a dust
collecting vessel and a condenser with connecting pipes between said vessels said
pipes being made of sections arranged at right angles to each other and extended
beyond their points of intersection and closed by detachable covers and valved
steam pipes entering through said covers in line with the axis of the sections so as
to permit the convenient cleaning of all of the sections of the connecting pipes
from the dust collected in the same substantially as set forth.
9. In an apparatus for making aceton a dust collecting vessel provided with a
heating coil at its lower part a vapour supply-pipe and a discharge pipe having a
dust catcher below the outgoing end of the discharge pipe substantially as set
forth.
151
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.