Improvements in Treating Vegetable Substances in order to obtain Fibrous Materials for Textile Purposes, and Pulp for We
Year: 1884

page_text: Improvements in Treating Vegetable Substances in order to
obtain Fibrous Materials for Textile Purposes, and Pulp for
We THOMAS GRAHAM YOUNG of Durris, in the County of Kincardine, North
Britain, Gentleman, and JOHN PETTIGREW, Junior, of Dinside in the same County,
Chemist do hereby declare the nature of our said invention for "IMPROVEMENTS IN
TREATING VEGETABLE SUBSTANCES IN ORDER TO OBTAIN FIBROUS MATERIALS FOR
TEXTILE PURPOSES, AND PULP FOR MAKING PAPER AND FOR OTHER USEFUL
APPLICATIONS to be as follows, that is to say :-
"3
The said Invention has for its object the treatment in an improved manner of
any vegetable substance capable of yielding fibrous materials for textile purposes, or
pulp for making paper, and for other useful applications; and it is advantageously
applicable to wood and other vegetable substances which are not easily reduced to
pulp by ordinary processes. The Invention is applicable to vegetable substances in
a raw or moro or less manufactured condition.
The Invention consists in boiling or digesting the vegetable substanco in
a solution of or containing nitrous acid; and in subsequently treating the substanco
with a solution of an alkali, of an alkaline earth or of an alkaline salt. In carrying
out the Invention the vegetable substance and the solution of nitrous acid aro
placed in a suitable boiler and heat is applied by preference so as to make the
solution boil; and provision is by preference made for condensing and returning to
the boiler the portion of the solution which evaporates. The boiling is continued
until the vegetable substance is found to be disintegrated; the solution of nitrous
acid is then drained off and a solution of an alkali or of an alkaline earth, or of an
alkaline salt is added and the vegetable substance is digested therein by preference
with the aid of heat. It is an advantage of the process that it bleaches the
cellulose to a cortain extent or facilitates the subsequent bleaching operations.
Dan 1:11.
L
1004
EDMUND HUNT,
Applicants' Agent.

page_text: Improvements in Treating Vegetable Substances in order to
obtain Fibrous Materials for Textile Purposes, and Pulp for
COMPLETE SPECIFICATION.
We, THOMAS GRAHAM YOUNG, of Durris in the County of Kincardine, North
Britain, Gentleman, and JOIN PETTIGREW, Junior, of Dinside, in the same County,
Chemist, do hereby declare the nature of our said invention for "IMPROVEMENTS
IN TREATING VEGETABLE SUBSTANCES IN ORDER TO ORTAIN FIBROUS MATERIALS
FOR TEXTILE PURPOSES, AND PULP FOR MAKING PAPER AND FOR OTHER USEFUL
APPLICATIONS and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement, that is to say:―
"
Our said Invention has for its object the treatment in an improved manner of
any vegetable substance capable of yielding fibrous materials for textile purposes or
pulp for making paper and for other useful applications; and it is advantageously
applicable to wood and other vegetable substances which are not easily reduced' to
pulp by ordinary processes. Our Invention is applicable to the vegetable substances
in a raw or more or less manufactured condition.
Our Invention consists in boiling the vegetable substance in a solution of or con-
taining nitrous acid; and in subsequently treating the substance with a solution of
an alkali, of an alkaline earth, or of an alkaline salt.
In carrying out our Invention the wood or other vegetable substanco is placed in
a suitable vessel or boiler and a solution of the acid is added to it in quantity
'sufficient to cover the substance. The strength of the solution will require to be
varied in different cases, but in treating ordinary pine wood the solution may
contain about 20 per centum of acid. The action of the acid is aided by heat which
may be applied so as to raise the temperature within the vessel or boiler to about
the boiling point of the solution.
The vessel or boiler is connected by a pipe or pipes to a condenser in such a way
that liquefiable vapors arising from the solution may be condensed and returned to
the vessel or boiler. The time during which the boiling should continue will vary
with the various vegetable substances treated, about 40 minutes being a suitable
time for ordinary pine wood, whilst a shorter time is sufficient for esparto grass.
When the boiling operation is completed the solution is run off, and adhering
acid can be removed by washing or otherwise.
The partly trented fibrous materials aro next placed in a suitable vessel or boiler
to be treated with an alkali or alkaline earth or alkaline salt. As an example it
inny be stated that for treating wood a suitable solution contains about 5 per centum
by weight of caustic soda for the original weight of the wood. In this alkaline
solution the fibrous materials are kept at a boiling temperature or nearly so for
about 30 minutes, under atmospheric pressure; or a higher pressure may be used,
in which case less time will be required.
The first part of the herein before described processes acts on the resinous or other
matters associated with the fibres; and the second part of the process removes
these matters in such a way that the fibres are reduced to a pulp which may be

page_text: washed and bleached and afterwards dealt with like ordinary pulp. The spent
soda solution may be treated in the ordinary way for recovering the soda.
The acid used in the first part of the process may be obtained in the vessel or
boiler by acting on a nitrite with an acid or acid salt; and the presence of small
quantities of other acids or of other impurities will not prevent the desired action
from taking place.
The gaseous oxides of nitrogen resulting from the oxidising action on the matters
associated with the vegetable fibres may be recovered by leading them from the
condensers to a tower in which they are acted on by air and steam.
The acid solution may be used for acting on two or more successive charges of
vegetable materials; and when exhausted or much contaminated with foreign
matters it may be subjected to distillation whereby a large portion of the acid may
be recovered so as to be usable over again. The residue in the still will contain
some oxalic acid and some nitric acid, both of which may be recovered.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed, we declare that what
we claim is
1. The treatment of vegetable substances capable of yielding fibres suitable for
paper making and other purposes with a solution of nitrous. acid substantially as
and for the purposes hereinbefore described.
2. The combination of the process forming the subject matter of the preceding
claim with the subsequent treatment of the product theroby obtained with
a solution of an alkali or alkaline earth or alkalino salt, substantially as herein-
before described.
Dated this manteninth d
1007
EDMUND HUNT,
Applicants' Agent.