This process using calcium acetate has the objection that an insoluble residue of sulphate of lime is left in the still and is difficult to remove.

A large part of the necessary equipment for the manufacture of acetic acid must be made of copper and is therefore expensive. Since the acetic acid industry has been established in this country for over 60 years, the manufacture of necessary equipment has become well established in this country and the American producers are in no way at a disadvantage in procuring equipment.

Acetic acid from calcium carbide.-Large war demands for acetone as a solvent for explosives led to the commercial development of a process for making acetic acid from calcium carbide. It was intended to convert the acetic acid produced by this process into acetone, but this proved too expensive and only acetic acid was produced.

This process was developed at Shawinigan Falls, Quebec, by the Canadian Electro Products Co. Calcium carbide, which is produced at Shawinigan Falls in large quantities, is first treated with water to form acetylene gas, which is then chemically combined with water in the presence of mercury salts as acatalyst to form acetaldehyde. The acetaldehyde is then oxidized to acetic acid. The acid produced is of high purity and concentration in contrast to that produced from acetate of lime, which requires several distillations to concentrate and purify it.

The original plant, with a capacity of 700 to 800 tons of acetic acid (100 per cent) per month, was destroyed by an explosion in the latter part of 1918. During the war the Canadian firm erected another plant with funds advanced by the United States Government. This plant was practically completed at the signing of the armistice, and soon after was put into operation. The disposition of claims of the Canadian firm against the United States Government, amounting to over $1,000,000, has not been announced up to the present time (December, 1920). The Canadian firm, however, controls the patent rights on the process and the necessary water power at Shawinigans Falls and is alone familiar with the technical details.

The productive capacity of the present plant is about 650 tons per month of 100 per cent acetic acid.

Acetic acid by fermentation. In the production of acetone by fermentation of molasses acetic acid is produced as an intermediate product and then converted into acetone. The United States Industrial Chemical Co., at Curtis Bay, Md., produced about 35 tons of acetic acid (100 per cent) from molasses residues during the war. The molasses is first fermented to alcohol, which is recovered and converted into acetic acid by another fermentation, which involves percolation over wood shavings carrying the proper bacteria.

Organization. In recent years many of the manufacturers of acetate of lime have taken up the production of acetic acid instead of selling the acetate of lime to other manufacturers to work up into acetic acid and acetone. Some of the larger consumers, such as paint manufacturers, purchase acetate of lime and produce their own acetic acid for the manufacture of pigments. The question of whether it is more economical to produce acetic acid at the source of acetate of lime (wood distillation plants) or at the point of consumption must be decided by local conditions.

Production and consumption. The production of acetic acid increased in quantity from 58,000,602 pounds in 1909 to 75,303,375 in

1914, while the value decreased from $1,336,874 in 1909 to $1,272,294 in 1914. The value is probably a truer indication of the industry, owing to the various strengths of acetic acid that are produced. The number of establishments producing acetic acid has remained practically constant at 13 since 1899.

Exports. Acetic acid is not shown in the export tables of commerce and navigation. If acetic acid is exported the quantities have been small. It usually is the practice to export acetic acid in the form of acetate of lime and convert this into acetic acid at the point of consumption.

IMPORTS INTO THE UNITED STATES.

The imports of acetic acid have decreased from about 1,000,000 pounds in 1910 to about 28,000 pounds in 1914, and the larger part imported in 1914 was free of duty under the act of October 3, 1913. From 1914 to 1918 the imports increased and have been between 200,000 and 500,000 pounds, or less than 1 per cent of domestic production. During the fiscal year 1919 the imports show a marked increase to 1,252,649 pounds, valued at $224,482. The first six months of the calendar year 1920 shows a marked increase in imports of acetic acid to 2,029,975 pounds, valued at $259,927.

The following table shows the imports of acetic acid since 1910:

Imports of acetic acid for consumption in the United States.

1 Product of specific gravity not exceeding 1.047.

2 Product of specific gravity exceeding 1.047.

3 From July 1 to Oct. 3, 1913.

4 From Oct. 4, 1913, to June 30, 1914.

5 Of this total, 1,227,988 pounds valued at $218,092 came from Canada.

PRICES.

The price of crude acetic acid (28 per cent) has increased two to three times over the normal prewar price of about 2 cents per pound. Glacial acetic acid (99 per cent) has shown a greater increase, the price in 1916, reaching a high level of about six times the normal price of about 8.5 cents per pound. From February 13, 1918, to January 1, 1919, the price of acetic acid was fixed by the Government at 15 cents per pound of 100 per cent acetic acid, and the price of glacial acetic acid at 19 cents per pound. During 1919 the price of the 28 per cent grade of acetic acid declined from about 5 cents per pound to 23 cents in July. This price was in force until about April, 1920, when there was an increase to 3.62 cents and a further increase in July to 34 cents per pound.

A compilation of prices on 28 per cent and 80 per cent acetic acid from Canadian and domestic trade journals shows that the price in Canada is considerably higher than the price in this country. The difference at times was as much as 100 per cent of the United States prices. Care should be exercised in drawing conclusions on the basis of trade journal quotations, as they often do not represent prices at which the larger portion of the goods are sold at.

Comparison of prices of acetic acid in Canada1 and the United States.2

1 Canadian prices are compiled from Canadian Chemical Journal.

2 Prices in United States are compiled from Oil, Paint, and Drug Reporter, and are for spot, wholesale, New York market.

TARIFF HISTORY AND TARIFF CONSIDERATION.

Acetic acid prior to the passage of the act of 1913 was dutiable. The duty with the exception of the period covered by the act of 1894 has been specific. A lower duty was assessed on acetic acid of a specific gravity less than 1.047 and a higher duty on acetic acid exceeding this specific gravity. The act of 1894 levied an ad valorem duty of 20 per cent. The act of 1913 placed acetic acid on the free list. This resulted in an increase in imports. The imports since 1914, notwithstanding this increase, have been small in comparison with domestic production.

Canada imposes on crude acetic acid of any strength not exceeding 30 per cent a duty of 25 per cent ad valorem, and on acetic acid n. o. p. a duty of 15 cents per gallon on any strength not exceeding strength of proof (strength of proof 6 per cent of absolute acid), and 2 cents for each degree of strength in excess of proof.

This difference in the duties existing in Canada and the United States on acetic acid gives the manufacturer in Canada an advantage over the producer in this country. The Canadian producer is able to keep the price of acetic acid at a higher level than the price prevailing in the United States. The manufacturer in Canada is able to ship acetic acid into the United States, but the Canadian duty naturally prevents manufacturers in this country from competing in the Canadian markets. This competition from Canada is likely to increase, owing to the synthetic production of acetic acid from calcium carbide as described in the preceding pages.

Should a duty be levied on acetic acid in this country, an ad valorem duty would seem to be preferable, owing to the numerous strengths of acetic acid.

The following table shows the duties levied on acetic acid by the various tariff acts since the act of 1883:

NOTE. Acetic acid having a specific gravity of 1.047 contains approximately 35 per cent of actual acetic acid.