Improvements in the Manufacture of Acetic Acid.
Year: 1899

page_text: Date of Application, 1st June, 1899
Complete Snonification Loft 6th Fab
1000
Mecanted
10th Ma
1000
Improvements in the Manufacture of Acetic Acid.
We, THE UNITED ALKALI COMPANY, LIMITED, of 30, James Street, Liverpool,
in the County of Lancaster, and MAX MUSPRATT, of the same place, Chemist, do
hereby declare the nature of this invention to be as follows:-
Hitherto great difficulty has been encountered in the economical obtainment
of pure glacial acetic acid from commercial pyrolignates. The usual methods
hitherto employed for the decomposition of pyrolignates, either by hydrochloric
acid or sulphuric acid (or acid sulphates) yield either an acid too weak for econo-
mical conversion into glacial acetic acid, or an acid too impure for direct rectifi-
cation.
We conduct the decomposition of pyrolignates with sulphuric acid and subse-
quent distillation in vacuo whereby acetic acid is obtained with facility
in such a state of purity as to be suitable for rectification without the necessity of
the complicated methods of purification hitherto employed. The acetic acid
obtained by the decomposition and distillation in vacuo of pyrolignates with com-
mercial sulphuric acid is subjected to a second distillation in vacuo and the strong
acetic acid obtained by this second distillation in vacuo is then introduced into
rectifying apparatus when the acetic acid is divided into a small quantity of weak
commercial acetic acid and a large quantity of practically pure glacial acetic acid.
Dated this 1st day of June 1899.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Acetic Acid.
We, THE UNITED ALKALI COMPANY, LIMITED, of 30, James Street, Liverpool,
in the County of Lancaster, and MAX MUSPRATT, of the same place, 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:-
Hitherto great difficulty has been encountered in the economical obtainment
of pure glacial acetic acid from commercial pyrolignates. The usual methods
hitherto employed for the decomposition of pyrolignates, either by hydrochloric
acid, or sulphuric acid, (or acid sulphates) yield either an acid too weak for econo-
mical conversion into glacial acetic acid or an acid too impure for direct rectifi-
cation.
By the decomposition of pyrolignates with sulphuric acid and subsequent distilla-
tion in vacuo, for example as described in the Specifications of Letters Patent

page_text: Nos. 34779 and 3987% granted on communications from Carl von der Linde,
acetic acid is obtained with facility in such a state of purity as to be suitable for
rectification without the necessity of the complicated methods of purification hitherto
employed. The acetic acid thus obtained by the decomposition and distillation
in vacuo of pyrolignates with commercial sulphuric acid is, according to this
invention, subjected to a second distillation in vacuo and the strong acetic
acid obtained by this second distillation in vacuo is then introduced into rectifying
apparatus when the acetic acid is divided into a small quantity of weak commercial
acetic acid and a large quantity of practically pure glacial acetic acid.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what
we claim is:-
The manufacture of acetic acid by subjecting acetic acid obtained by decomposi-
tion and distillation in vacuo of pyrolignates with sulphuric acid to treatment in a
rectifying apparatus substantially as hereinbefore described.
Dated this fith day of February 1900.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.