Improvements in the Manufacture of Cellulose.
Year: 1890

page_text: Date of Application, 15th Oct., 1890
Complete Specification Left. 15th July, 1891-Accepted, 5th Sept., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Cellulose.
I, EMIL MISCH, Chemist, of Vienna, Kaiser Josefstrasse 15, in the Empire of
Austria do hereby declare the nature of my invention for IMPROVEMENTS IN THE
MANUFACTURE OF CELLULOSE to be as follows:-
My invention relates to improvements in the manufacture of cellulose from
wood of all kinds by a so called macerating process, for paper making and
other purposes.
In opening up of the wood in order to produce cellulose by a macerating process
it is essential that the wood be mechanically reduced, for instance to wood wool,
before the same is subjected to the effects of the chemicals employed.
The wood wool or finely reduced wood employed in my improved process is
produced by mechanical means in well known manner. This mechanically prepared
wood is first steamed for about three hours at a temperature of from 100 to
120° Centigrade in order to dissolve the resinous parts of the incrustations of the
wood and thus not only prevent the aci·lulation of the soda lye subsequently used
but allow the same macerating lye to be repeatedly employed when the proportion
of soda spent is added to the same. After the steaming is finished the water is
let off and the hot macerating process carried out in the same vessel, that is, with a
soda lye at a temperature of about 150 to 160 C.
The concentration of the soda lye in a hot bath of this kind must of course vary
according to the class of wood under treatment said lye or alkaline bath varying
on the average from 10069 to 1598 specific gravity.
Now in order to carry my said invention into effect I proceed as follows giving
for instance the treatment of pine wood although I wish it to be understood that
not only pine but any desired kind of wood can be submitted to my process.
Wood wool produced for instance from pine wood of a cross section of about
1x4 inches is first placed in an appropriate vessel then steamed at a temperature
of 100 to 120° C. for about 3 hours and the surplus water drained off; then a
10 per cent. strong soda lye or thereabouts added until the lye covers the wood wool
which is allowed to remain about 5 to 6 hours under a pressure of from 5 to 6
atmospheres at such low temperature that no oxalic acid is formed.
The alkaline lye is now let off and the wool treated in the centrifugal machine
so as to remove all superfluous lye after which the said wood wool or reduced
wood is subjected to the action of chlorine gas in the following manner.
The reduced wool which has been treated in the centrifugal machine is now
placed in an appropriate reservoir or receptacle of cement, wood or other suitable
material, the receptacle closed gas tight and chlorine gas led into the same.
During the action of the chlorine gas on the wood wool, chlorate of soda and
hypochlorite of soda are formed which dissolve the gluten in the wood.
chlorine gas. is generated in known manner from a mixture of peroxide of
manganese and ordinary muriatic acid and in the well known apparatus for
generating chlorine gas.
The
For treating 1000 kilogram (20 cwt.) of wood wool about 25 kilo. (50 lbs.) of
peroxide of manganese and the corresponding quantity of muriatic, acid will be
required the said wool being subjected for about 6 to 8 hours to the action of the
chlorine gas after which the wood wool thus treated with chlorine is subjected to
a cold macerating process for which purpose the wool is placed in an appropriate
soda lye of about 2 per cent. strength poured over the same until the wool is covered
After this cold
by the lye and allowed to lay for 1 to 2 hours in the same.
maceration the opened up cellulose is treated in an edge mill until the bundles of

page_text: fibres of the cellulose appear to be uniform after which the said cellulose is washed
in a suitable apparatus.
The macerating lye which has been repeatedly used-ten or more times-will
appear viscid in consequence of the matter extracted from the wood and is therefore
subjected to an evaporating process until a firm mass is attained and this mass
subjected to fractional distillation.
Valuable neutral hydrocarbons are obtained by means of this fractional dis-
tillation and the residue in the boiler is then heated to glow heat air being admitted
whereby the organic substances are consumed and soda mixed with fine powdered
carbon remains behind which can be again converted into caustic soda for opening
up fresh quantities of wood.
Dated this 15th day of October 1890.
W. P. THOMPSON & BOULT;
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Cellulose.
I, EMIL MISCH of Vienna in the Empire of Austria, 15, Kaiser Josefstrasse 15,
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:-
My invention relates to improvements in the manufacture of cellulose from
wood of all kinds by a so called macerating process for paper making and other
purposes.
In order to produce cellulose by a macerating process it is essential that the
wood be mechanically reduced, for instance to wood pulp, before the same is
subjected to the effects of the chemicals employed.
The wood pulp or finely reduced wood employed in my improved process is
produced by mechanical means in well known manner. This mechanically prepared
wood is first steamed for about three hours at a temperature of from 100 to
120° Centigrade in order to dissolve the resinous parts of the wood and thus not
only prevent the acidulation of the soda lye subsequently used but allow the same
macerating lye to be repeatedly employed when the proportion of soda spent is added
to the same. After the steaming is finished the water is let off and the hot
macerating process carried out in the same vessel, that is with a soda lye at a
temperature of about 150 to 160° C.
The concentration of the soda lye in a hot bath of this kind must of course vary
according to the class of wood under treatment said lye or alkaline bath varying
on the average from 1-0069 to 1-598 specific gravity.
Now in order to carry my said invention into effect I proceed as follows giving
for instance the treatment of pine wood although I wish it to be understood that
not only pine but any desired kind of wood can be submitted to my process.
Wood pulp produced for instance from pine wood of a cross section of about
1x inches is first placed in an appropriate vessel and a 10 per cent. strong soda
lye or thereabout added until the lye covers the wood pulp which is allowed to
remain about 5 to 6 hours under a pressure of from 5 to 6 atmospheres at such low
temperature that no oxalic acid is formed.
The alkaline lye is now let off and the pulp treated in the centrifugal machine so
as to remove all superfluous lye after which the said wood pulp or reduced wood is
subjected to the action of chlorine gas in the following manner.
The reduced wood which has been treated in the centrifugal machine is now
placed in an appropriate reservoir or receptacle of cement, wood or other suitable
material, the receptacle closed gas tight and chlorine gas led into the same. During
the action of the chlorine gas on the wood pulp, chlorate of soda and hypochlorite
of soda are formed which dissolve the gluten in the wood. The chlorine gas is

page_text: generated in known manner from a mixture of peroxide of manganese and ordinary
muriatic acid and in the well known apparatus for generating chlorine gas.
For treating 100 kg. (2 cwt.) of wood pulp about 25 kg. (50 lbs.) of peroxide of
manganese and the corresponding quantity of muriatic acid will be required the
said pulp being subjected for about 6 to 8 hours to the action of the chlorine gas
after which the wood pulp thus treated with chlorine is subjected to a cold
macerating process for which purpose the pulp is placed in an appropriate soda lye
of about 2 per cent. strength poured over the same until the pulp is covered by the
lye and allowed to lay for 1 to 2 hours in the same. After this cold maceration
the opened up cellulose is treated in an edge mill until the bundles of fibres of the
cellulose appear to be uniform after which the said cellulose is washed in a suitable
apparatus.
The macerating lye which has been repeatedly used-ten or more times-will
appear viscid in consequence of the matter extracted from the wood and is therefore
subjected to an evaporating process until a firmn mass is attained and this mass
subjected to fractional distillation.
Valuable neutral hydrocarbons are obtained by means of this fractional distilla-
tion and the residue in the boiler is then heated to glow heat air being admitted
whereby the organic substances are consumed and soda mixed with fine powdered
carbon remains behind which can be again converted into caustic soda for opening
up fresh quantities of wood.
Having now particularly described and ascertained the nature of my said inven-
tion and the manner in which the same is to be performed I declare that what I
claim is:
1. The employment of wood pulp for the purpose of producing cellulose sub-
stantially as described.
2. Steaming the wood pulp for the purpose of dissolving the resinous parts of
the wood, by which means the acidulation of the lye is hindered and the latter
rendered capable of repeated employment substantially as described.
3. The employment of a hot macerating process, with soda lye at a temperature
of 150-160° C. only, for the purpose of hindering the formation of oxalic acid and
destroying the structure of the wood substantially as described.
4. The treatment of the macerated wood pulp with chlorine, in which process
besides chlorate of soda hypochlorite of soda is formed which latter dissolves the
gluten of the wood.
5. The cold macerating process by the aid of a weak soda lye substantially as
described.
6. The regeneration of the soda lye after repeated use by evaporating the lye
subjecting the residue to fractional distillation and heating the resulting matter to
glow heat in the presence of air substantially as described.
7. In the fractional distillation covered by Claim 6, the production of neutral
hydrocarbons as valuable subsidiary products of the manufacture of cellulose as
described.
Dated this 15th day of July 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.