’!
i
1
1
i
i
*
i
Staff-Industry coCCamoratme R. L. DEMMERLE Associate Editor
.
W. A. TAEBEL AND W. F. ANDERSON E i m r & Amend, New York, N. Y.
in collaboration with
,
T
HE quality of reagent chemicals rank6 with the precision . . ’ . of scientific mstruments as a major physical determinant of the accuracy of the work of chemists and chemical engineers. Alm& every development in chemistry and its allied fields may be attributed, directly or indirectly, to improvements in the
The quest for purity began in the era of the alchemist. Most recipes for the much sought philosopher’s stone contained d e tailed instructions regarding the purification of the ingredients (I#,18, 18). Failures in transmutation of the base metals were often ascribed to the existence of impurities in the starting m a t e rials (17). Many of the operations now used for the purification of chemicals had their oricin durinp this oeriod. Because of the relirioioua fervor of the times, the recorded dacriptions and nomenclature of these operations had a strong spiritual f l a v o v t h a t is, distillation was termed ascension and condensation, dascension. T h e important purifying step now known as sublimation was likened by the alchemists to an “upward flight of doves” and called ex-
manufacture, performance, and standardization of laboratory apparatus and chemicals-the tools of the chemist. The modern acientiat, although quick to lavish Drake and a& ~. tention on improved instrumentation, has at the same time taken for granted the predictable nature and high quality of the chemical reagents that line his laboratory ShelveS. Behind their informative labels and constantly increasing variety, however, lie years of effort by many individuals and organizations.
~
2
~.
~~~
~
~~~~
~~~
~~
January 1950
INDUSTRIAL AND ENGINEERING CHEMISTRY
altation or elevation. When the operation was repeated several times, it was supposed t o yield the quintessence of the original substance (19). The dawn of the science of chemistry placed new emphasis on the need for experimental materials of a reasonably certain composition. Although the early chemists were able t o secure some of their materials from apothecary shops, much of their time had t o be spent in the preparation of their reagents from natural substances. Many of the basic discoveries during chemistry’s first 100 years were coincident with the synthesis or fractionation of laboratory reagents from crude commercial mateiials (14). It was common practice for the chemists of t h a t time t o exchange with their colleagues the purified compounds they had prepared, in order t o gain a greater variety of reagents in their laboratories. About the middle of the nineteenth century, the demands of photography and increased medical and pharmaceutical knowledge led t o the beginning of a fine chemicals industry in Europe, principally in Germany ( 5 ) . The chemist benefited immeasurably from this development and until World War I reagents from German firms such as C. A. F. Kahlbaum and E. Merck filled a high percentage of the demands of the world’s laboratories. I n America, the industrial revolution brought the establishment of some of our currently well-known fine chemical concerns, but there was a much greater emphasis on the building of a heavy chemicals industry. Laboratory supply houses were forced t o imporf the majority of their reagents already packaged for distribution or in bulk for subsequent packaging. T o a lesser extent, they shopped among the domestic chemical industries for selected cuts of its production suitable for reagent use. American enterprise in reagent manufacture began t o take form about the beginning of this century. Merck & Company, a n established importer, began domestic manufacturing about this time (9). Baker and Adamson was founded in 1901 and a few years later the firm was bought and enlarged by the General Chemical Company (6). I n 1904, J. T. Baker, one of the founders of Baker and Adamson, formed his own firm at’Phillipsburg, -U. J. (6). Other American companies began t o devote more of their attention t o the manufacture of reagent grade chemicals, but the infant industry still had t o face the keen and experienced competition of foreign firms in the American market. As recently a s 1914, the majority of fine chemical and reagent firms in business in this country were either the branch offices or sales agents of German companies (4). The British blockade of Germany in World War I caused the United States t o expend more effort in developing its limited facilities for the production of fine chemicals. The reagent segment of the industry acquired its share of attention but the shortage of laboratory grade chemicals, especially organics, grew worse and had assumed critical proportions at the time the United States entered the war. The appearance of reagents of inferior quality on the market caused President Stieglitz of the AMERICAN CHEMICAL SOCIETYt o appoint a special committee on analyzed reagents under W. F. Hillebrand t o recommqd specifications for these materials (10). A year later this Eonmnitte_e-wassucceeded by a permanent committee under the chairmanshig of E. Emmett Reid (6). The wartime shortages caused chemists once again t o prepare many of their reagents. I n 1914, C. J. Derick of the University of Illinois initiated a system of vacation-time laboratory work during which students prepared the reagents most urgently needed for the coming semester. I n 1916, Roger Adams took over the project and enlarged it to supply chemists outside the university (6). At about this same time the Imperial College at South Kensington in England founded an exchange bureau through which British chemists and institutions could barter chemicals (80). I n the decade that followed the war, American facilities for the manufacture of laboratory reagents expanded considerably.
3
Eastman Kodak organized its organic chemicals department i n 1919 as a domestic source of fine organic reagents. The Mallinckrodt Chemical Works announced the creation of a reagent chemical department in 1922, a consequence of its long experience in the production of photographic and other fine chemicals (6). Four years later the General Chemical Company built a plant at Marcus Hook, Pa., to expand the capacity of its Baker and Adamson division (8). I n 1927, Merck & Company consolidated with Powers, Weightman, and Rosengarten Company, another fine chemicals company (9). Although there was a tendency on the part of some t o return t o German sources, American firms by the mid-twenties were in a position to supply a wide variety of reagent grade chemicals. Improvement in the techniques used in manufacturing reagent grade chemicals has resulted in raising their general level of purity. Absolute purity, as determined by sensitive analytical procedures, has been approached in many products. I t s complete achievement, however, would be technically and economically infeasible and cannot be considered the goal of the industry. he working principle that is followed in the preparation n t is t o lower and keep its impurities beneath the conns t h a t would interfere with the course of the prepondera n t majority of the reactions in which it may be used. I n those cases where a commercially available reagent is not sufficiently p u e for a particular purpose, the user or manufacturer, working on special order, can usually carry the purification t o the desired higher state. STANDARDIZATION
As the reagent industry grew, it became apparent t h a t the increased exactness of chemistry made it necessary t h a t the chemist be informed and assured of the maximum limits of impurities in his reagents. Critics asserted t h a t the term “chemically pure” was by itself meaningless (15)and t h a t the initials C.P. stood only for the conscience of the producer. Similar fault was found with the indiscriminate use by British manufacturers of the term “analytical reagent”; one authority claimed t h a t the initials A.R. merely designated a product that was all right (20). It is generally believed t h a t informative labeling of reagents began in Germany in 1888 when Krauch, under the auspices of E. Merck, published the first book on standards and methods of testing reagent chemicals (11). Labels began t o appear with the analyses for impurities given in the ambiguous terminology of trace, faint trace, and very faint trace, a marked contrast to current labels which often list the results of as many as fourteen different determinations. According t o Haynes, Eimer & Amend of New York was the first firm t o market a line of reagents bearing an exact analysis of the impurities present ( 7 ) . Early attempts in this country t o establish uniform standards for drugs, medicines, and some chemicals were the publication of the first Pharmacopeia of the United States in 1820 ( I @ , and the first National Formulary in 1888 (3). Subsequent revisions of these works have included numerous specifications for chemicals suitable for reagent use. However, the emphasis placed on medicinal and pharmaceutical chemicals has limited their value t o chemists. I n recognition of this situation the Committee on Analytical ReAMERICANCHEMICALSOCIETY’S agents in 1921 published a series of specifications and testing methods for common laboratory reagents. Since t h a t time, this work has been republished and enlarged until i t now includes specifications for more than 150 reagents ( 1 , 2). These standards serve as a valuable yardstick in maintaining the high and uniform quality of the reagent grade chemicals made in this country. EDGEWATER, N. J., PLANT OF ElMER & AMEND
Eimer & Amend, a major supplier of laboratory apparatus and chemicals, began in 1851 as a drug store on the lower East Side
INDUSTRIAL A N D ENGINEERING CHEMISTRY
4
