T. Howard Deighton.

The struggle for supremacy : being a series of chapters in the history of the leblanc alkali industry in Great Britain online

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(one of the 47 chemical works associated under
the name of THE UNITED ALKALI COMPANY), before
the erection of his works for the manufacture of soda
by the Leblanc process, used the ammonia-soda


process for about two years, producing several
tons a day ; but, owing to engineering difficulties,
he abandoned this method of preparing alkali
in favour of the Leblanc system. It is in the
mechanism, apparatus and appliances necessary
for the successful use of this process that Solvay
will be remembered, and not as an inventor of
the process itself. The chemical transformation,
which will be described in a future chapter, was
known almost before Solvay was born, but to
Solvay is rightly due the honour of making the
process commercially successful.

The process has these enormous advantages,
that it leaves practically no solid residue, and that
it requires singularly little fuel, less than half of
that used in the Leblanc process. Simple as the
process is it presented tremendous mechanical
difficulties, which Solvay's ingenious inventions
finally overcame. The u Solvay" ammonia
process was introduced at Northwich in 1872
by Dr. Ludwig Mond, the celebrated chemist and
inventor, to whose enlightened philanthropy we
owe the Davey- Faraday Research Laboratory of
the Royal Institution, founded and endowed by
Dr. Mond in 1896. The ultimate result has been
that the ammonia process established at Northwich
directly above the salt deposits has assumed
enormous proportions, and has revolutionised
the alkali trade of Great Britain, and largely
supplanted the classic method of Leblanc for
producing the carbonates of soda. Further details
of this economical system will be given when the


great salt mines of THE UNITED ALKALI COMPANY
near Fleetwood, and the ammonia soda works at
the same place pass under review. It may well
be asked how the historic Leblanc system can
continue to exist in the presence of the newer and
cheaper process. The answer is afforded by the
value of those waste products to which frequent
reference has already been made. The acid fumes-
given off in the first stage of Leblanc's system
furnish the basis of the manufacture of bleaching
powder and chlorates, in fact, these by-products
are more valuable than the alkali (sodium
carbonate) itself.

The grey muddy residue obtained in the
second stage of the Leblanc process has also been
converted to profit by causing it to yield up the
sulphur which it contains in a state so perfectly
pure that it commands the highest market price,
and is superior even to the famous Sicilian product.

Thus, by utilising waste products cast aside
as useless by a former generation, the modern
manufacturer turns the famous but ancient
Leblanc process to good account. The price of
alkali has naturally fallen with the advance of the
industry, especially since the introduction of the
Solvay process. In 1800 the price of soda crystals,
then manufactured from the ashes of seaweed, was
60 per ton. When Mr. Muspratt commenced
operations his soda crystals were sold at ^18 per
ton, and soda ash at 24. To-day the first quality
soda crystals may be purchased, free on board at
Liverpool, at 3 js. 6d. per ton.


POSSIBLY in no department of chemical
science has the practical genius of the
British chemist been more apparent than in the
profitable utilisation of the materials thrown aside
as waste in the processes of manufacture of
some chief product. The coal-tar colour industry
furnishes an illustrious example of this remarkable
instinct of perceiving potentialities in the most un-
promising material. Before Sir William Perkins's
epoch-making discovery of mauve, the jubilee of
which has lately been celebrated (see The Times of
July 27th, 1906), coal-tar was looked upon as a
necessary but evil accompaniment of the distillation
of coal during the manufacture of coal gas, and
large sums were paid to have the noxious stuff
carted away, buried or burnt.

It was seen in the last chapter that Leblanc's
ingenious process, for the conversion of salt into
soda, yielded two products which were looked
upon by him, and for many years by his successors,
as unavoidable wastes, nuisances inseparable from


the manufacture of soda. The one was a fuming
acid gas, thrown off in enormous volumes at the
moment when the sulphuric acid comes into
contact with the common salt ; the other was a
grey, muddy sediment with an offensive smell.
The first of these, now always called hydrochloric
acid gas, was allowed to escape into the air, with
the result that it devastated the neighbourhood,
killing off all vegetation by its corroding action.
In the early days of the soda trade no attempt
was made to condense these tremendous fumes,
and, so long as the extent of manufacture was
small, the inconvenience was borne by the neigh-
bouring public, but in 1823, after the abolition of
the salt tax, when Mr. James Muspratt, senior,
erected works in Liverpool for the manufacture
of soda by Leblanc's process, matters reached a
crisis. The noxious gas was evolved from Mr.
Muspratt's chimneys in torrents beyond endurance,
and Liverpool rose in revolt. Ultimately the
Corporation compelled Mr. Muspratt to remove
his works to Newton. This caused the attention
of practical men to be turned to the subject of
utilising this waste product. The difficulty arose
chiefly from the immense volumes of gas to be
dealt with. Though a man of remarkable enter-
prise and foresight, Mr. Muspratt was sceptical
as to the possibility of condensing the prodigious
quantity of vapour, and when an invention for the
purpose of absorbing the hydrochloric acid gas
by means of water was submitted to him by Mr.
William Gossage, Mr. Muspratt retorted that "not



all the water in the falls of Ballyshannon would
condense the gas from his works." Nevertheless,
in 1836, Mr. Gossage completely solved the
problem by devising the now familiar " condensing
towers," in which a descending stream of water
meets and absorbs the ascending fumes ; and so
successfully did " Gossage's towers" perform their
task that, in the Alkali Act of 1863, the government
made it incumbent upon all Alkali manufacturers
to condense 95 per cent, of their hydrochloric
acid fume. In actual practice, since the value
of this "waste" gas has been demonstrated, the
condensation is so complete that only a trace
of the obnoxious acid fumes escapes into the

Hydrochloric acid contains only two elements,
hydrogen and chlorine. Of these chlorine is
commercially the important member. About ten
years after its discovery it was found to possess
most astonishing bleaching properties. In April,
1785, before the French Academy of Sciences in
Paris, the famous chemist Berthollet read a paper
which was published in the Journal de Physique
for May of the same year. He there mentions
that he had tried the effect of the gas in bleaching
cloth, and found that it answered perfectly. This
at once set upon its track certain enterprising
active-minded people, who foresaw great potenti-
alities in this heavy, offensive, green gaseous body.
In 1786 the celebrated James Watt, inventor of
the modern condensing steam engine, visited Paris,
and there Berthollet exhibited his experiments to


his distinguished fellow-scientist and inventor.
On returning to England Watt commenced a
practical examination of the subject, and was
accordingly the first man to introduce bleaching
by chlorine into this country. The commercial
practice of this now universal method of whitening
cotton goods was first tried in some bleach yards
near Glasgow, the property of a Mr. Macgregor,
Watt's father-in-law. The new process could
accomplish in a few hours what had hitherto taken
open-air exposure during a whole summer to effect.
The records of the time show that it was regarded
as an amazing feat that 1,400 pieces of gray
muslin despatched on Tuesday to the bleachers
were returned on Thursday to the manufacturers
bleached and finished and ready for immediate use.
In early days chlorine gas was prepared by
heating a mixture of common salt and black oxide
of manganese with "oil of vitriol" (sulphuric acid).
The gas for the purpose of bleaching was simply
dissolved in water ; but in this form its use was
attended with grave harm to the workmen. This
was partly remedied by the addition of potash to
the water, producing a bleaching solution called
" Eau de Javelle" by its first makers. The most
important advance, however, was to absorb the
gas in finely divided slaked lime. This was the
idea of Mr. Chas. Tennant, of St. Rollox, Glasgow,
grandfather of the late Sir Chas. Tennant, Bart.,
the 1 3th April, 1799, Mr. Tennant obtained a
patent for the manufacture of chloride of lime in a


state of powder. This simple but effective process
laid the foundations of a huge and ever-extending
industry, and the St. Rollox Works, which began
in a small way over a century ago, were for a long
time the largest manufactory of bleaching powder
in the world. The preparation of chlorine as
described above was expensive, chiefly owing to
the residues which ran to waste, carrying off with
them all the manganese and two-thirds of the
chlorine. To recover these lost products was
indeed a problem well worthy of attention. To
the ardent chemist the word "waste" is like the
proverbial red rag to the bull. There is no such
thing as waste. It is only matter misunderstood,
misapplied, and in the wrong place. The problem
was ultimately solved in 1869, by Mr. Walter
Weldon, of London, who, after long -continued
devotion of time, labour and money, perfected an
ingenious and cheap process for the recovery of
the manganese. With the friendly assistance of
Sir David Gamble, Bart., C.B., Vice-President of
Manganese Recovery Process " was first practised
in the works of Messrs. J. C. Gamble and Sons, at
St. Helens (one of the constituent firms comprised
practically revolutionised the bleaching powder
manufacture by largely reducing the cost of
production. The work of this ingenious English
inventor, who died in 1885 at the early age of 52,
offers another instance of the discovery of latent
wealth in so-called "waste."


Though Weldon's invention obviated the loss
of manganese, it did not recover that portion of the
chlorine which was still finding its way down the
drain pipes in the shape of calcium chloride. The
extensive loss of so valuable an element could not
long be tolerated, and in 1870 the late Mr. Henry
Deacon, one of the founders of the firm of Gaskeli,
Deacon & Co., of Widnes (now incorporated in
the co-operation of his brilliant assistant, Dr.
Ferdinand Hurter, a remarkable and very scientific
means for the preparation of chlorine without any
use whatever of manganese, in which also all the
chlorine in the salt is recovered. This was the
Mr. Deacon who, as related in the last chapter,
was actually working as far back as 1853 the
famous "new" soda-ammonia process. Deacon's
invention gave an immediate additional value to
those troublesome fumes of hydrochloric acid
which, as described, had been the bugbear of the
early alkali manufacturers. The process, like all
great inventions, is in its essence extremely simple,
but, like many other successful experiments, it
failed to act when first applied on the large scale
necessary for commercial purposes. The laboratory
method consisted of passing pure hydrochloric
acid gas over heated copper salts at a given
temperature. The gas was decomposed into its
elements. Chlorine was evolved, and the copper
salts appeared to be inexhaustively active ; but on
the large scale how different ! The small impurities
in the vast quantities of the fuming gas quite


upset all the calculations, with the result that the
majority of those who adopted the process gave it
up in despair, and for a quarter of a century it did
not make much headway. But patience and
perseverance have finally overcome the technical
difficulties, and have rendered the "Deacon"
process the cheapest means in existence for
producing chlorine from hydrochloric acid, and
THE UNITED ALKALI COMPANY the largest chlorine
product manufacturers in the world. Thus, after
many years, the first stage of the classical Leblanc
process was rounded off by the complete and
profitable utilisation of all "waste" material
thrown off during the manufacture of saltcake.

It will be remembered that in the second
stage of the famous Leblanc process a grey muddy
sediment remained, which up to recent years was
cast away and dumped in ever-growing hillocks
outside the chemical works, there to yield, when
soaked with rain, exhalations offensive to the nose
and drainings poisonous to the neighbouring
streams. It may now be briefly described how
British chemists have extracted wealth from this
waste, and at the same time created a complete
cycle of operations in the Leblanc process, so that
no useless residue is left. Everything is now
converted into saleable products or is utilised in
some further stage of operations.

The Leblanc process first demands that salt
shall be decomposed by sulphuric acid. Now,
sulphuric acid cannot be prepared without sulphur,
and sulphur was, and still is, a costly substance.


Without entering into the complex chemical
reactions, it may be stated at once that all the
sulphur in the sulphuric acid ultimately finds its
way into this abominable refuse tipped by millions
of tons upon the banks of the Mersey, Tyne and
Clyde. Innumerable experiments were made to
recover the valuable sulphur, but, when tried upon
a commercial scale, the processes were either rank
failures or too costly to yield any profit. One of
the best of these inventions was that devised
about 1867 by Dr. Ludwig Mond, to whose
philanthropic endeavours to further the progress
of chemical research in this country reference has
already been made. But Mond's process only
succeeded in recovering about half the sulphur
from the "waste," so that there was still room for
a more efficient system which would extract all
the sulphur. Mr. William Gossage, of Widnes,
sometimes styled the "father of the alkali trade,"
devoted a fortune and 30 years of his life to the
solution of the problem, and, though unsuccessful,
he pointed out in 1861, with wonderful prescience,
the lines upon which the ultimate solution would
take place. It was reserved for Mr. Alexander M.
Chance, of Oldbury, Birmingham, in 1888, to
solve the problem which had baffled so many, and
his process is now adopted by most of the large
alkali makers working the Leblanc system. Mr.
Chance makes use in one stage of his system of a
kiln invented by Mr. C. F. Claus, of London, so
that the sulphur recovery process is usually spoken
of by the joint name Chance-Claus.


Limitations of space, and the intrinsic techni-
calities of the subject preclude any description of
this remarkable process, in which air and the
waste gases from lime kilns effect the recovery of
the precious sulphur.

The industrial use of sulphur is on the
increase. It is employed in enormous quantities
in the manufacture of gunpowder, washing-blue,
vulcanised rubber, in the bleaching of woollen and
silk goods, in disinfectants and preservatives, and
the wood-pulp paper industry alone consumes
about 200,000 tons per annum of this element.
The commercial recovery of chlorine and sulphur
from "wastes" has not only prolonged the
existence of the Leblanc system of alkali
manufacture, but has also rendered it highly
improbable that this classic process will ever
die out. The quantity of soda made by it will,
however, be measured by the demand for the
by-products, for the soda-ammonia process yields
none of these valuable "wastes." To-day it would
be almost more correct in the Leblanc works to
call soda the by-product in the manufacture of
chlorine and sulphur.


IN the year 1838 occurred a curious episode in
the soda manufacture, which shows that fiscal
weapons may often prove to be two-edged. In
that year " Bomba," King of Sicily, thought that
his miserable revenue would be improved if he
granted to a certain pushing French firm a
monopoly of the export of sulphur, the chief
product of the island. At this time sulphuric acid
was exclusively manufactured from brimstone
(sulphur) obtained from Sicily. The monopoly
was granted, and the price at once was advanced
from $ to 14. per ton, a figure which threatened
the existence of the alkali industry, at that time
mainly centred in Great Britain. Diplomatic
intervention by England ultimately secured the
withdrawal of the monopoly, but so far as the
alkali industry was concerned it was too late to
benefit Sicily ; and for more than a generation the
sulphur market was entirely disorganised. For it
was soon found by chemists that there was a
cheaper and inexhaustible supply of sulphur in
certain minerals, and they immediately began to


avail themselves of this source for the manufacture
of sulphuric acid. When still later the Chance-
Glaus process, described in the last chapter,
showed the way to the recovery of the sulphur lost
in the "tank-waste," the plight of the Sicilian
industry became worse. Wages were reduced to
starvation rates, ruin and revolution appeared to
be impending, and the Italian Government was
petitioned to assist the island by removing the
then existing export tax of about 8s. per ton.

When at first the metalliferous sulphides
began to be substituted for pure sulphur, the ore
from our own Cornish mines was used, and also
that from certain deposits near Wicklow in Ireland.
But of recent years the main supply of "pyrites"
has come from Spain, where abundant deposits of
ore are found containing a high percentage of
sulphur combined with copper, irtm, and arsenic,
together with minute quantities of silver and gold.
By roasting the pyrites, the greater proportion of
the sulphur is expelled, and the residual cinders
were for many years thrown away as worthless,
and accumulated in great heaps, being deemed
-even scarcely good enough for road metal, for
which they were sometimes used. Now these
unsightly refuse heaps contained whatever small
quantity of copper had been present in the original
ore. In some instances the pyrites had not
contained more than one per cent, of this metal,
and it was not thought worthy of extraction. But
the idea of the latent wealth in these tip-heaps
disturbed the minds of many chemists, and in



1850 the late Mr. Wm. Gossage purchased some
of these accumulations of so-called rubbish, and
erected works at Widnes, for the extraction of the
copper by smelting processes.

But when Spanish pyrites began to be used
this mode of working was superseded by a brilliant
process carried out by yet another British inventor,
Mr. William Henderson, of Glasgow, who in 1859
took out a patent for a method of converting the
copper in the "waste" to copper chloride by
grinding the pyrites cinders to powder, mixing
them with a small proportion of salt, and then
roasting the mixture in a current of air. The
copper chloride thus formed is easily dissolved out
by water, carrying with it in a soluble form all the
silver and gold. By a simple process devised by
Mr. Frederic Claudet, of London, the silver and
gold can be easily and cheaply extracted from
solution by means of iodide of potassium. The
final residue, after the extraction of the more
valuable metals, is a purplish powder consisting of
practically pure iron-oxide. In the works of THE
UNITED ALKALI COMPANY some 150,000 tons per
annum are produced of this residue, which, either
in the form of "purple ore," or pressed into
briquettes and baked to render the blocks coherent,
finds a ready and profitable sale amongst the
blast furnace proprietors, for conversion into pig
iron. Thus once more is waste turned to wealth,
and the Leblanc soda industry again reinforced
by the great value of the residuals occurring in the
manufacture of sulphuric acid from cuprous pyrites.


It was stated above that the pyrites contained a
certain amount of arsenic. Now arsenic is a very
volatile body, and at a moderate temperature is
turned into vapour. This deadly poison has,
however, certain valuable properties to the chemist,
which give it a considerable commercial value.
In the manufacture of glass and glazes it has a
distinct use, and hence commands a good price
in the market. A profitable future awaits the
discovery of a cheap and easy process for capturing
the arsenic at the moment when it is vaporised
during the roasting of the pyrites. Many highly
ingenious methods have been devised in the Central
Widnes, but like many brilliant laboratory devices,
these methods have only in part fulfilled the
hopes of their inventors when applied on the large
commercial scale. At the moment of writing a
method is being tried which promises complete
success. There are still technical difficulties to
overcome, but that these will be ultimately
conquered cannot be doubted. These experiments,
carried on at great cost, involving the services of
a staff of trained chemists (of whose work more
remains to be said), afford an instance of the
determination of this great Company to maintain
the supremacy of this country in an industry
which is of national importance.

The process of soda manufacture originally
devised by the genius of the Frenchman Leblanc,
has been so developed that modern works would
be absolutely unrecognisable by the original


inventor. Although to-day the manufacture of
alkali by this process is still practised in Germany
and in America, the apparatus, methods, and
inventions of the great pioneers who created the
alkali industry in Great Britain have been adopted
elsewhere without modification.

In the manufacture of the " heavy chemicals "
this nation has for nearly a century been pre-
eminent, and it is the intention of the Directors of
supremacy as far as British brains and skill can
secure it. In this endeavour every patriot will
wish them success, for the loss of a trade employing
millions of capital and thousands of men, and the
decay of a staple industry which, as was seen in
the first chapter, is the mother of a thousand other
industries, could not be viewed with equanimity.

About 40 years ago a cloud began to appear
upon the horizon, which for many years over-
shadowed the prosperity of the Leblanc industry.
It had long been known that if "bicarbonate of
ammonia" is added to a strong mixture of salt
and water, what is known in chemistry as a double
decomposition occurs, and "bicarbonate of soda"
is formed, which settles down as a precipitate.
This is a much shorter cut to the production of
the carbonates of soda (soda-ash and soda-crystals)
than that found by Leblanc. But, as described
in the second chapter, the chemical engineering
of the time was not equal to the problem of
conducting this process upon a profitable com-
mercial scale, until Ernest Solvay, a young Belgian


inventor, overcame the engineering difficulties and
started manufacturing alkali by the ammonia
process at Couillet, near Brussels. Leblanc
invented a process, Solvay an apparatus.

The economic revolution effected by Solvay's
invention was stupendous. No Leblanc manu-
facturer could produce soda ash so cheaply, and
when, in the "seventies," Messrs. Brunner, Mond
and Co. established works at Northwich to
manufacture alkali by Solvay's process, an era of
disastrous competition set in which threatened to
destroy the Leblanc industry. Indeed, if the
manufacturing exponents of the latter had been
confined to the production of soda, they would
before now have been driven from the field.
The by-products utilised, as already described,
for the manufacture of bleaching powder, chlorate
of potash (used enormously for making safety
matches, percussion caps, explosives, &c.), chlorate

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Online LibraryT. Howard DeightonThe struggle for supremacy : being a series of chapters in the history of the leblanc alkali industry in Great Britain → online text (page 2 of 5)