Year: 1898

page_text: Date of Application, 15th Nov., 1898-Accepted, 4th Feb., 1899
I, NICOLAS BASSET, of 58, Rue Truffaut, Paris, 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:-
A number of persons have sought to treat cellulose, in order to convert it into
dextrin, and afterwards into glucose and alcohol. In fact this treatment has been
made a kind of accessory to the manufacture of paper pulp obtained from wood
fibre. Recently, it has even been proposed to treat the saw dust in a perfectly dry
condition with diluted sulphuric acid, by means of a more or less large amount of
superpressure and a superheating of the atmosphere, consequently and necessarily,
in a closed vessel. I entirely reject the idea of superpressure and the superheating
in a closed vessel because I consider that it is always undesirable to increase the cost
and difficulties of manufacture.
Concentrated sulphuric acid cannot be employed for treating cellulose, owing to
the heavy expense connected therewith, and the risk of forming double acids, which
lead to almost insurmountable difficulties in connection with the neutralisation.
On the other hand, weak acid has but very little, indeed scarcely any effect at all on
the cellulose, when the operation is carried on in the open or free air, that is to say,
under the only conditions which are really practical.
1st. Accordingly, for the sulphuric acid solution which is to act on the cellulose
I prefer a mean density of 10° .= 1075, a liquid containing per litre 95 grammes
of anhydride or 116 grammes 375 milligrammes of monohydrate. This proportion
seems to me to be the best for operations in the open air.
2nd. The raw material which contains the cellulose or a substance capable of
conversion into cellulose is disunited or divided by any suitable mechanical
means; it is washed as may be necessary in order to free it from objectionable
salts and subjected during a variable time to the action of the weakened sulphurio
acid. The temperature is raised more or less according to the object to be attained,
at from 50° to 60° more dextrin is produced and less glucose; at boiling point the
reverse is the case.
3rd. I arrange a series of vats, varying in number, and protected against the
action of the sulphuric acid, and furnished with a valve or any suitable means for
filtration by means of which the liquid can be conveyed to the next vat, with the
assistance of a pump or other liquid raising device or otherwise. The residuum of
ach vat is "exhausted" as may be considered desirable by sufficient pressure, after
being washed.
4th. Into vat No. 1, I introduce a thousand parts of sulphuric acid at a density
of 1075 and raise the temperature by any known means of heating, suitable to
he nature of the vessels.
5th. In the most ordinary case, tlat in which the object in view is the production

page_text: of glucose, the liquid is heated to boiling point after a first portion of the disunited
or divided material has been placed in it. It is then stirred and, after being
boiled twenty or twenty five minutes, there is added a second portion of the dis-
united or divided material, equal to about one seventh of the total to be used.
The liquid is again stirred and, after the lapse of the same space of time, a fresh 6
portion of the material is once more added and so on, the boiling being continued.
The means proportions, may be considered as 360 parts of sawdust to 100 parts
of sulphuric mono-hydrate.
6th. The liquid from the first vessel, being drawn off, is conveyed into the
second; to this is added the product of the partial washing of the residuum, the
liquid is heated to boiling point-and the material is added in the proportions and
manner indicated above, the same course being pursued with the third vessel, and
so on until a quantity of the material has been acted on equal to nine or ten times
the weight of the acid.
I
7th. The residuum of the vessels may be "exhausted" (by the action of a fresh
proportion of diluted acid,) a quantity of fresh material proportional to that which
has been "solubilised" being however added. Generally speaking, and without
limiting my action thereto, I prefer to wash tho residuum until it is neutralised and
to use it by any known processes, for the preparation of oxalic acid or methylio
alcohol, apart from my chief operation.
8th. Instead of employing fresh additional matter for the purpose of restoring the
proportions in vat No. 1, it is better to effect this by means of the residuum of
No. 2 which in turn is completed by a suitable quantity of the residuum from No. 3.
The last is restored by fresh material.
9th. In case only one vessel is available, the following course is pursued, except
with slight variations. Preparation of the acid solution at 10° or 105° B., boiling
produced, introduction of a portion of disunited or divided material equal to about
one seventh of the total to be used; stirring, addition of a fresh portion, after
twenty or twenty five minutes and so on until the whole has been added. Then,
continued boiling and stirring for an hour, drawing off of the liquid; washing to the
point of exhaustion and pressure of the residuum; remixing of the liquids.
10th. The liquid is a sulphuric solution in which there is acid, dextrin and
glucose in a certain proportion of water. This liquid, weakened to 5º B. or even
Tess, by the water used in washing, is boiled for an hour and a half for effecting the
conversion. It is then neutralised with lime; the neutral liquid is separated by the
ordinary means and fermentation then proceeded with:
11th. My treatment of the cellulose differs from all those which have been
attempted, by reason of the divided course or arrangement which I adopt in work-
ing in the open or free air; but in addition to this I differ from all that may
have been done inasmuch as I utilise the residuum of the cellulosic material. This
utilisation constitutes an operation apart, independent, and from an economic point
of view indispensable, and it is effected by means known and employed, industrially
for converting the cellulose into oxalic acid or methylic alcohol, entirely isolating
the ammonia resulting from the azote of the material. In the same manner the
sulphate of lime resulting from the neutralisation enables the sulphuric acid
employed to be regenerated, by a standard method known and described in
chemistry.
=
12th. On the average, 1000 parts of soft saw-dust treated with 270 to 273 parts
of acid at 66° B. reduced to 100 B. density 1.075 will give from 250 to 340 parts
of hydrocarbonated material, soluble by my method of division in the open or free
air, as indicated above. On the other hand I use as raw material not only divided
and disunited ligneous matters and saw-dust, white, soft or otherwise, but also all
kinds of vegetable matter containing a larger or smaller proportion of cellulose, such
as sca-wrack, straw, hay, grass, leaves, roots and barks, waste materials, as grape
cake, pulps from which the starch or the sugar has been eliminated, in short all
vegetable matters which produce cellulose or substances capable of conversion into
cellulose, expressly reserving to myself the use of these materials in the production,
by my method of division, of soluble cellulose or dextrin, glucose and alcohol.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
The treatment of cellulose or of materials capable of conversion into cellulose,
with the object of converting same into dextrin, and then into glucose and pure
alcohol, the said treatment consisting in the division of the cellulose material in
presence of sulphuric acid at a mean density of 1.075 (10° B.), at a temperature
not exceeding boiling point, in the open or free air by progressive action and the
subsequent utilisation of the residuum and the recovery of the acid employed by
means and processes already known and in common use, these last two operations
being independent of my process and my general method of treatment, the whole
substantially according to the preceding detailed description.
Dated this 14th day of November 1898.
F. W. GOLBY,
36, Chancery Lane, London, W.C.,
Patent Agent for the Applicant.