Improvements in the Manufacture of Ethyl Alcohol.
Year: 1898

page_text: Date of Application, 9th Aug., 1898-Accepted, 15th Oct.. 1898
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Ethyl Alcohol.
I, FREDERIC R. COUDERT, Junior, of 100, Broadway, New York City, United States
of America, Lawyer, 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 :—
This invention relates to a process for manufacturing ethyl alcohol consisting
essentially in subjecting acetylene gas to the action of a reducing agent which absorbs
the acetylene and converts it into ethylene; the agent may be regenerated by the
action of nascent hydrogen, and is therefore capable of producing an indeterminate
quantity of ethylene from acetylene. The invention therefore includes the reduction
or regeneration of the reducing agent by the action of nascent hydrogen generated
by electricity or by chemical action.
The object of the invention is to produce a very pure quality of alcohol at very low
cost.
For this purpose the apparatus shown in the accompanying drawing may be used in
the manner about to be described, by way of example.
Figure 1 is a diagrammatic view partly in elevation and partly in vertical section,
showing the general construction and relation of the several parts of the apparatus.
Figure 2 is a vertical section of a portion of the absorption apparatus to an enlarged
scale.
The successive steps and the general principles of the process are as follows:-
There is first introduced into a suitable vessel, 5, a determined quantity of calcium
carbide (CaC), for instance one ton, say 1000 kilogrammes.
To this is added
sufficient water to decompose it forming calcium oxide and acetylene gas. From one
ton of calcium carbide there are developed about 400 kilogrammes of acetylene gas.
The acetylene gas (CH2) so formed, is transmitted through the pipe 6, and brought
into contact with, and absorbed by a solution of a reducing salt contained within the
vessel 7, such for instance as a double salt of ammonium and chromous sulphates.
Chromous sulphate is known only in solution, and it is well known that the
ammoniacal solution of this salt absorbs oxygen, nitric oxide, and acetylene.
The formula (NH4)2SO4 + CrSO₁ + Aqua for the ammonium chromous sulphate is
based by analogy upon the formula K2SO4 + CгSO4 + 6H2O, but it is also possible that
the forinula is (NH4)2SO4 + 2 Cr SO. + Aqua.
The strength of the solution should be sufficient to yield hydrogen by weight,
equal approximately to ten per cent of the acetylene gas used, i.e., for 400 kilogrammes
of acetylene gas there should be available 40 kilogrammes of hydrogen. The result
of this action is the formation of ethylene gas (C.H.) and the oxidation of the
reducing agent to form a compound containing chromic oxide Cr₂O₂:
The following equation shows how the nascent hydrogen required to transform
the C₂H₂ into C₂H₁ may be obtained from the solution of chromous and ammonium
sulphate.

page_text: convert 400 kilogrammes of acetylene into 430 kilogrammes of ethylene is
approximately 11-216 kilogramines. In practice it is preferable to heat the solution
of the reducing salt to approximately 40° C which may be accomplished by means of
the burner 8, or other suitable source of heat. The heating of the solution is not
essential, the increase of temperature merely adds to the rapidity with which the
process takes place.
The oxidized reducing salt may be readily reduced to its former state by submitting
it to the action of nascent hydrogen, which may be conveniently produced by any
suitable electrolytic apparatus, such for instance, as that shown in Figure 1, and
which consists of the dynamo 9, and electrodes 10 and 11. These electrodes are
enclosed within the vessel 7 and immersed in the solution contained within the
vessel. The positive electrode 10, is enclosed in the tube 12, open at the bottom
and at the top, which communicates with the atmosphere so that the oxygen gas set
free by this electrode may escape into the atmosphere.
The hydrogen which is generated at the negative electrode is set free directly
in contact with the solution of the reducing agent, and as the hydrogen is nascent,
it acts to reduce the oxidized solution to its original condition, probably according to
the equation:
Cr.2(SO4) (NH)₂SO + H₂
==
Nan
2 Cr.SO₁ + H₂
It will be observed that it is not necessary to make use of the large quantity of the
reducing salt mentioned (11.216 kilogramines) as a given quantity (the amount
depending upon whether the reducing salt is acted upon constantly or at
intervals), is capable of producing an indeterminate quantity of ethylene from
acetylene.
The nascent hydrogen necessary to reduce the salt may be produced by well
known chemical means; for instance, by the action of dilute sulphuric acid on iron
or zinc.
Instead of using the particular salt mentioned, any other suitable reducing agent
which will transform the acetylene into ethylene and may be itself regenerated,
without appreciable loss of weight, may be used. The ethylene gas which is produced
is slightly heavier than the acetylene gas; 400 kilogrammes of acetylene gas produce
about 430 kilogrammes of ethylene gas.
The ethylene gas produced as above described is transmitted by the tube 13 to the
absorption apparatus 14. Any suitable absorption apparatus may be employed. That
shown at 14 consists of a series of cells 15, arranged in progressive order downward,
and a series of pipes 16, dipping into the cells, and arranged in progressive order
upward. These cells are filled with sulphuric acid from a suitable receptacle 17. The
ethylene passing through the pipe 13 reaches the pipe 16, thence through the
sulphuric acid cell 15, thence through the pipe 16a to cell 15a, and so on through
the series, the gas being fully absorbed before reaching the top of the series of cells.
Preferably the sulphuric acid is heated to about 85° C. (For 430 kilogrammes.of
ethylene there will be required about 1400 kilogrammes of concentrated sulphuric
acid.) By this combination of ethylene and sulphuric acid, there is formed hydrogen-
ethyl-sulphate, which gradually works its way downward into the retort 18. To the
solution of hydrogen-ethyl-sulphate in the retort 18, there is added about thirty-three
per cent. of water, the mixture is .then raised to the boiling point by means of a
burner 8, or other suitable heating apparatus whereupon ethyl alcohol vapour passes
off, through the tube 19, and is condensed in the vessel 20, (any suitable condenser
will serve the purpose) and finally passes into the vessel 21 as chemically pure ethyl
alcohol. This completes the process.
It will be understood from the foregoing that the particular apparatus shown and
described is in nowise essential, as any suitable apparatus known to chemists may be
employed. Neither is it essential that the process be carried out by acting at
intervals upon the reducing salt by nascent hydrogen, as it is evident that the

page_text: acetylene gas may be continuously discharged into the reducing solution, and this
solution continuously acted upon by the nascent hydrogen set free by the action of
the electric current traversing the solution.
The process above described may be indicated by the following formulæ :-
It will be observed from the above formulæ that the only materials consumed are
water, calcium carbide, and hydrogen. The reducing or converting agent is, as
previously explained, transformed from the state of sesqui-oxide to its original state,
(protoxide) by nascent hydrogen generated chemically, or by electrolytic action,
which latter requires but a small expenditure of mechanical energy.
The sulphuric acid, after the ethyl alcohol has been separated from it is in a con-
dition to be used again. Thus by the process described an ethyl alcohol is produced
which is chemically pure, and not accompanied by other alcohols, fusel oils, ethers,
etc., poisonous in character, or by other products of fermentation, as is the case with
alcohol produced in the usual way. Further, the cost of producing the alcohol,
owing to the low cost of calcium carbide, is much less than by any known process.
In practice it has been found that the cost of the alcohol produced is very little in
excess of that of the calcium carbide consumed.
It should be understood that the invention is not limited to the employment of the
particular chemical specified, as the agent for converting or transforming (these terms
are used as synonomous) the acetylene into ethylene gas. The materials, however,
which have been mentioned are those which I consider best adapted to accomplish
the results stated. There are other chemicals which have a similar action, and are
readily regenerated by nascent hydrogen, without appreciable loss of weight.
Although these various chemicals are not mentioned in the specification, they are
well known to chemists, and may all be considered equivalents and within the scope
of the invention.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described process for manufacturing ethyl alcohol, by decomposing
calcium carbide by water to form acetylene, subjecting the acetylene to the action of
a double salt of ammonium and chromous sulphates or other equivalent agent to form
ethylene, absorbing the ethylene so produced in sulphuric acid, forming hydrogen
ethyl sulphate heating the solution of this in water so as to effect distillation of ethyl
alcohol, and regenerating the reducing agent by subjecting its solution to the action
of nascent hydrogen.
2. As part of the process above referred to the conversion of acetylene into ethylene
by the action of a substance capable of effecting that conversion and of being itself
regenerated by the action of nascent hydrogen.
3. As part of the process above referred to the regeneration of the reducing agent
employed to transform acetylene into ethylene, by subjecting the said agent to the
action of nascent hydrogen.
Dated this 9th day of August 1800
ABEL & IMRAY,
Agents for the Applicant.