An Improved Method of Obtaining the Salts of Nicotine, or Kindred Alkaloids, in a Concentrated State from the Vegetable Substances which contain them.
Year: 1898

page_text: COMPLETE SPECIFICATION.
An Improved Method of Obtaining the Salts of Nicotine, or
Kindred Alkaloids, in a Concentrated State from the Vegetable
Substances which contain them.
I, JOHN URI LLOYD, of corner of Plum and Court Streets, Cincinnati, State of
Ohio, one of the United States of America, Engineer, 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 consists of an improved mode of obtaining the salts of nicotine or
kindred alkaloids in a concentrated state from the vegetable substances which contain
them.
The vegetable alkaloids are best represented for the purposes of this Specification
by the familiar alkaloid of the tobacco plant, nicotine; therefore for the sake of
brevity and simplicity the descriptive portion of this Specification will be restricted to
the extraction and recovery of nicotine from tobacco stems and leaf-refuse. But it is
clearly to be understood that other alkaloids than nicotine may be obtained by the
process described without departing therefrom in any material particulars.
Nicotine is liberated by volatilization from the vegetable fibre containing it, at a
temperature of about 2250 Centigrade. The recovery of volatilized nicotine is, how-
ever, conditional upon its not coming in contact with flame or with a red heat.
By means of the process and apparatus herein described, nicotine may be com-
pletely distilled from tobacco waste and recovered in solutions susceptible of being
brought to a high degree of concentration, while at the same time the operation is
carried on at small cost; all the products and by-products of the process being
available for useful purposes.
The distillation by this process is open, the requisite beat being supplied by the
combustion of part of the tobacco waste. This combustion is carefully regulated and
all the resulting ash, tar and ammonia, is preserved.
The process will be understood in detail by reference to the drawing and the
following description which is addressed thereto.
The furnace or retort S, is charged with tobacco stems and waste through the feed
hole at E. The structure connected with the furnace S consists of a system of trapped
passages, as follows:
A flue F emerges from the top of furnace S and forms a passage for the products of
combustion and volatilization from the furnace.
This passage enlarges first in the form of a trap O, which contains a baffle-plate
shown in section at G. From the bottom of trap O there is an outlet o, which dips
in the vessel 01. Passing from the trap O, the passage continues as the flue F2 to
the tank H, and from tank H to tank I as pipe F, then from tank I as pipe F* to the
steam aspirator A, which intervenes and forms part of the continuous system. From
the aspirator A the pipe F5 passes into the final trap W, wherein are suspended or
fixed a number of baffle plates, such as N. From trap W a pipe (not marked in the
drawing) leads to the outer atmosphere.

page_text: Subsidiary features of construction are the valve F1, which closes automatically to
prevent any back draught to furnace S. R is a valve in flue F2, which can be closed
by hand, for purposes hereinafter to be described. C is a storage tank to receive the
liquid drawn from tank H, such liquid carries a large percentage of nicotine and
ammonia in solution and is ready for concentration as hereinafter mentioned. C also
catches the liquid from trap 01. B is a receptacle for the liquid of tank I. J is a
pipe connecting the bottom of receptacle B with the top of tank H. K is a valve for
opening or closing pipe L, which serves as a conduit of communication between the
vessel B and the tank H¹.
In the top of tank I is a funnelled inlet M, adapted to receive the contents of the
tank L which in its turn receives the liquors from the trap vessel W, wherein they
have been condensed. Strainer plates P, P, for distributing the vapor current are
located in tanks H and I.
When the aspirator A is in action the valve R being open and valves K and L
closed, the vapors emerging from the retort S are drawn through the successive pipes
and tanks. In each tank there is a quantity of dilute sulphuric acid.
Oxalic, phosphoric or tartaric acid could be used in these tanks; or, instead of an
acid solution, any kind of oil in which nicotine is soluble (such as one of the heavier
petroleum distillates), might be substituted; but it is believed that such a substitu-
tion would involve a sacrifice of economy.
Instead of an aspirator at A, a fan or pump exhauster may be employed with good
results, but it is believed that such a contrivance is not susceptible of so nice local
adjustinent as the aspirator.
The furnace S is charged with tobacco stems and scraps through the feed hole at E.
The draught is then turned on at A, and the tobacco stems, or some suitable
kindlings, are ignited at the bottom of the column of vegetable fibre in the furnace S.
Doors D are provided with the usual dampers and air inlets in such manner that the
air is admitted evenly through the mass at the bottom of the furnace. The perforated
false bottom Q assists the even distribution of air through the furnace. Ashes may
be withdrawn from the said doors when desired.
The heat of combustion in the burning zone passes up through the mass of tobacco
and volatilizes the nicotine and kindred alkaloids. The draught carries over into the
pipes F, F, etcètera, and the connected vessels all the smoke and vapor which contain
the nicotine and other alkaloids, ammonia and tar.
The trap O, for which any ordinary tar scrubber might be substituted, intercepts a
large portion of the tar and water carried over in the vapors, which pass therefrom to
the tank H, and are sucked through the liquid in the trap formed by tank H and the
lower end of pipe F2. The grating P breaks up the stream of nicotine-laden vapor
and distributes the rising bubbles all through the liquid in tank H. The tarry
products are delivered by pipe o to trap 01, from the top of which the tar and liquids
intercepted run off into tank C.
The vapors are similarly drawn through the system comprising tank I and trap
vessel W. In each tank the vapors pass through dilute sulphuric or equivalent acid
which takes up the nicotine so that when the exhausted products of combustion are
at last passed from trap tank W to the chimney practically all the valuable ingredients.
have been intercepted.
The liquor in the distilling apparatus should be used progressively. From trap
tank W the liquid is drawn automatically into the vessel L where acid is introduced.
Tank
is supplied through M with the liquor of vessel I.. Tank I delivers its liquor
to vessel B, when liquor in tank H has reached its point of maximum concentration,
and been drawn out.
Tank H is supplied from vessel B through pipe J in the following manner :
Normally, valve R is open and valves K and L. closed. Close valve R and open
valve L, and then drain the strong liquor from H through V¹ into tank C. Then close
valves V1 and K, and open valve I. The suction at A is then increased until it is
strong enough to draw the liquor from B through pipe J into tank H. During this

page_text: interval when valve R is closed a good opportunity is offered for feeding a fresh supply
of tobacco stems into S.
All the nicotine reclaiming liquid finds its way eventually into tank C, and from
this liquid the nicotine solution may be concentrated to a desired degree in any usual
manner.
Tanks H and I may be reduplicated as many times as may be found necessary for
thorough extraction of the ammonia and alkaloids.
A series of four such tanks, and holding a column of dilute sulphuric acid (6 per
cent. solution) about eighteen inches high above the perforated screen P will take
out of the passing vapors substantially all the ammonia and alkaloids.
In operation, the tanks H and I are filled with a 6% solution of sulphuric acid to a
level of about 18 inches above the screens P. Fire is started in the burner and the
draught at A turned on. As the burning progresses through the mass of tobacco
stems in S, fresh stems are fed in through F, at a rate equal to about 100 pounds
per hour for every seven square feet of cross section of the column of fuel.
The ashes are drawn out at D. After four hours run, all the acid in tank H will
have become neutralized by the ammonia and alkaloids passing through. Tank H is
then emptied into the storage tank C, and the contents of the successive vessels in
the system are moved up one tank toward the furnace and fresh acid is introduced
into the tank L to replenish it.
The liquid in the storage tank C is allowed to clarify by settling, is then concen-
trated and the sulphate of ammonia therein separated out by percolation with alcohol,
which dissolves and carries away the nicotine salts, leaving the ammonia salts which
are insoluble in alcohol. The alcohol may be recovered by distillation.
In performing the above described operation it is important to preserve the burning
zone and the volatilization zone in the furnace in distinct separation, because the
purpose of the process will be in whole or in part defeated if the nicotine is brought
in contact with a red heat or with flame. Therefore the combustions should be made
to progress uniformly through the mass in such manner that the nicotine will all be
volatilized before the vegetable fibre reaches an incandescent heat. Then when the
flame finally reaches any given mass of fibre it will have been reduced to a charcoal-
like fuel well adapted to complete and uniform combustion.
During the process of volatilization of the nicotine, etcetera, from the column of
fibre in the tobacco furnace it is well to watch the distribution of the combustion,
charring, and volatilization zones, the better to guard against any undue local advance
of the combustion.
For this purpose there may be inserted long narrow glasses in the side of the
furnace, at convenient intervals around the drum of it. The definition of the zones
will be perceptible to the operator who may adjust the progress of combustion from
time to time.
The zones of burning, etcetera, are of course not clearly and sharply marked, and
blend to some extent, but are none the less distinct from each other to the practical
observer.
The arrangement of the several zones is suggested by the drawing. In the lower
zone Z¹ the active combustion goes on and ash is formed, in the zone Z² next above,
the stems and woody portions of the refuse become charred and ready for burning;
in the zone Z³ the liberation of nicotine, etcetera, takes place.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, declare that what
I claim is
1. The process of extraction of nicotine and kindred alkaloids of tobacco, which
consists in igniting a column of tobacco at one end while confined in a chamber,
whereby the alkaloid is liberated in advance of combustion, drawing the liberated
alkaloid vapors through the mass of unburned tobacco, and then absorbing the
alkaloid vapors in an acid solution.

page_text: 2. The herein before described method of obtaining the salts of nicotine, or kindred
alkaloids, in a concentrated state from the vegetable substances which contain
them.
Dated thou11
T
1000
WM. BROOKES & SON,
55 and 56, Chancery Lane, London, Agents for the Applicant.