The training of analytical chemists for industrial research

training necessary for analytical chemists who are working in industrial research or development or on problems arising from sales service. In the fie...
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THE TRAINING OF ANALYTICAL CHEMISTS FOR INDUSTRIAL RESEARCH* 1. W. STILLMAN Experimental Station, E. I, d u Pont de Nemours & Company, Wilmington, Delaware

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DISCUSSING the question of what industry expects in the way of training for analytical chemists, it is necessary &st to outline the problem which is under consideration. For the purpose of this discussion the needs for analysts assigned to control work will not he reviewed. Instead, it is the intention to consider the training necessary for analytical chemists who are working in industrial research or development or on problems arising from sales service. In the field of analytical research analytical chemists are needed who have the inherent abilitv and trainiuc t o develoo new procedures independently. A distinction often is made between the terms "analytical chemist" and "analyst," and it is a valid one. The analytical chemist can he defined as one who is familiar with the means of carrying out an analysis but who is concerned primarily with the information to be obtained from the analysis and with the interpretation of this information. The analyst, on the other hand, appreciates the end in view but is concerned primarily with the means to be used. In other words, the "analytical chemist" is one who is able to develop new methods, use them, and properly evaluate the data obtained. An "analyst" is mainly a user of analytical methods. This discussion will consider the training required by the analytical chemist.

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INDUSTRIAL ANALYSIS

I t was not so long ago that the industrial analytical chemist was called upon t o identify and determine only those constituents of materials which were present in comparatively large amounts and t o make use of only relatively simple conceptions and methods. In the inorganic field determinations of the so-called "common" elements were called fo*. For an organic sample the estimation of carbon, hydrogen, nitrogen, sulfur, and halogens, sometimes supported by a saponification number, iodine number, or similar data, would generally su5ce to identify or estimate the major constituent. Now the situation is quite different. Practically any element in the periodic table may be encountered and frequently in trace amounts. The importance of these trace amounts can be illustrated by catalysts where very small amounts of certain elements are added as promoters and by fertilizers where some elements, when Contribution No. 268 from the Chemiml Department, Experimental Shtion, E. I. du Pont de Nemours and Company, Wilmington, Delaware.

present even in small amounts, have been found to have a pronounced effect on plant growth. Accurate aualyses for the less common elements present in uuusually low amounts are indispensable to research in these fields. In the organic field establishing the elementary composition of the sample marks the completion of only ths first step in the analysis. Questions to be answered are: How many substances are present? What functional groups are in these substances, and how are these functional groups arranged in the molecular structures? Are com~oundsinvolved which have the same ultimate composition and which respond to the same chemical reactions? Industrial analysis, therefore, is no longer limited to the detection and estimation of elements or relatively pure compounds but has been widened to provide detailed information about the compositions of complex materials and their properties. Increasingly complicated physical and physical-chemical measurements are widely used in the analytical field. Although not new, the specialized techniques of microanalysis are being emphasized and provide valuable information. The sample may consist of a hit of inorganic corrosion product on a telephone relay which is misbehaving, or it may be a few milligrams of a crystalline compound which has been obtained as the en.tire product from a long, tedious organic synthesis. The techniques of microanalysis have been developed to handle the minute samples available in such cases. These brief glimpses indicate some of the problems which the analytical chemist in industry faces every day. What, then, should be his training to have a successful career in this field? TRAINING FOR INDUSTRY

Perhaps a few requirements should be sketched to clarify the picture of what is expected of the analytical chemist. He should have the ability to define the scope of a problem. This mill include s broad appreciation of the objectives of the person for whom the aualysis is to be made. The analytical chemist should be able to recognize the possible approaches to his problem which ale open to him and should have some idea as to the relative merits of each. Having selected an avenue of approach, it may still be necessary for the analytical chemist to develop an entirely new analytical method. When he has decided upon a course of action, he should be in a position to see that the necessary manipulations

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are carried through, either by himself or by a suitable specialist. Finally, he will have to evaluate the data obtained and present the results in a suitable form that gives all the information obtainable by the procedures employed. The analytical chemist, if he is to do a complete job, must approach his work with an open mind and must not admit defeat until all avenues of approach have been considered. It is important for the analytical chemist to have the ability to work vith others on a cooperative basis. He may be called on to serve as a member of a.research team. In his own analytical field a complete analysis may not he a "one-man" job but the result of the efforts of several persons working closely together. As has just been pointed out, there must he a free exchange of information and understanding between the analytical chemist and the research chemist on all analytical problems. The development of good personality traits should not be neglected in the training of the analytical chemist. There are two broad levels of training and experience that are required for industrial analytical work, but a t both levels the point of view described in the previous paragraphs must be maintained. The analytical chemist, who is to supervise analytical work or who is to devote full time to analytical research, should have had graduate training. Before assuming a supervisory position, it would be advisable for him to spend some time carrying on industrial analytical research. For the analyst who is to carry out the actual analyses, a bachelor's degree from a college having a strong curriculum in chemistry and physics should be sufficient. In no case should the point of view he accepted that a person who could not qualify in other branches of chemistry would be satisfactory for analytical chemistry. As pointed out by R. B. Seymour,' "A premedical student who cannot make the grade does not become a routine physician nor does an orderly become a doctor of medicine after he has had six months' experience." THE COLLEGE TRAINING

The writer does not presume to dictate to educators exactly which courses should be given to provide the desired training but perhaps a few suggestions along broad lines will be in order. Tomany educatorsanalytical chemistry has meant primarily systematic inorganic analysis. The subject of the analysis of organic compounds has been treated somewhat incidentally along with the study of organic chemistry. This has tended to minimize the importance of organic analysis a t a time when, if anything, it should be receiving more emphasis than inorganic analysis because of the rapid expansion of the synthetic organic chemical field. Organic analysis should be treated as an integral part of analytical chemistry, and the principles to be applied should be studied alongside those of inorganic analysis. Dr. L. T. Hallett, through his many contacts with

industrial analytical chemists, is in a unique position t o present their point of view, and his editorial of December, 1945¶ gives an excellent outline of the training which can he suggested as desirable. One basic principle stands out clearly here and also in the comments of other leaders in the analytical field.a The first requirement in a curriculum should be that it emphasize the fundamental principles of chemistry and physics. There should be no foreordained plan to turn out a t the end of four years a complete analytical chemist. Rather, there should be presented to the student the basic knowledge in the sciences of chemistry and physics upon which as a foundation he can build later, either through graduate study or through actual experience in the laboratory while practicing his profession. The first course in ge7 era1 chemistry in the jreshman year i s the most important of all and should be presented by the most sldled teacher available. It should point the way to future work by making the fundamental principles stand out, using the descriptive material for illustrations. The course in qualitative analysis should illustrate principles, and it should not cover in detail the complete group separation scheme. In the laboratory, semimicro techniques may be used and experiments should be selected to demonstrate typical reactions. Much detail can be omitted. The qualitative course might include a brief description of the emission spectrograph and its use for identifying the inorganic elements. In quantitative analysis the reactions on which the methods are based should be the main focus, and reasons for any unusual steps in the procedure should be clearly given. The teaching of both qualitative and quantitative analysis affords an excellent opportunity to show how the principles of physical chemistry are applied in practice. If taught from this viewpoint, the student learns why certain steps are taken and does not become a slave to the details of a procedure. In the laboratory the student should be taught the different techniques that he will be called upon to use, and the emphasis should he on the importance of careful attention to each detail of the process, the development of manipulative skill, and a familiarity with the different analytical instruments. Experiments should be designed so that each demonstrates a principle, and there should not be a repetition of routine determinations. Attention should be given to precision and accuracy, not only from the abstract point of view but also to show how these principles may be used to select a suitable procedure to attain the desired objective. When a method that will give an accuracy of 1 0 . 5 per cent is adequate, it is poor policy to waste time and energy on attaining an accuracy of 0.01 per cent. The judgment required to make such a decision should he cultivated. The hroad training in chemistry for the student should he continued with courses in inorganic, organic, and 1

Anal. Chern., 19,941 (1947).

Ind. Eng. C h a . , Anal. Ed., 12, 748 (1945). Editorials, Anal. Chem., 19, 821-3, 941-2 (1947).

MARCH. 1950

physical chemistry. Since physics is used just as much as chemistry in analytical work today, courses in this subject should he required. Included in the courses in physics which should he placed early in the curriculum, there should be discussions of heat, light, and electricity. Especially important in the application of physics to analysis is the field of optics. Microscopy and the transmission of radiant energy in theultraviolet, visible, and infrared regions are important examples. Practically all recording instruments employ electronic circuits, and an understanding of the fundamental principles involved will he very useful. In the labor* tory there should be demonstrated among other things t4e principles of light absorption, the use of electrical instruments such as the potentiometer, and the assembly of simple electronic circuits. Mathematics should he studied for its usefulness and for mental discipline. English is the most important of the nontechnical subjects. The student must l e m to express himself well. He should he taught to pick out the essential points from his work and present them concisely and clearly. The conclusions to be drawn should stand out and should not he submerged in a tedious narrative. The analytical chemist will want to take his place as a useful citizen in his community so there should he time in his schedule for a balanced selection of the socalled cultural courses. The groundwork in a broad study of the different branches of chemistry and physics having been laid, there may be time in the senior year of college for electing a course in a more specialized field. The student interested in analytical chemistry should he encouraged to take a course in advanced quantitative analysis, in microanalysis, or in instrumental analysis. The advanced quantitative analysis might cover some of the more difficult and less common procedures, hoth inorganic and organic, and possibly include an introduction to such techniques as chromatography and partition as analytical tools. A course in microanalysis might include the use of microscopic techniques, spot tests, and the methods of Pregl for organic analysis. In instmmental analysis the emphasis should be on the principles of design and operation of the instmments und on the dewlopmrnt of ndequate interpretations of the d x t n ol)tained irom rht. instrummts. The ohiectivc of a survey course should not he to develop a &shed instmment operator. Such skill is easily attained with practice. h t h e r , the student should receive a clear impression of each type of instrument so that he knows its general field of application together with some of its advantages and some of its disadvantages. GRADUATE TRAINING

of analytical chemistry the graduate student will want more specific knowledge such as special methods of analysis, procedures for making difficult separations, techniques for avoiding interferences, and the extension of methods to the determination of trace amounts of elements. He will want to know more about the various analytical instruments available, details of the principles on which their operation depends, their particular application, and the advantages and disadvantages of the automatic or semiautomatic operation of certain instmments. Certain of the elective courses outlined for the senior year of undergraduate work could be of graduate caliber. Originality of thinking should he developed through the study of available procedures for a particular analysis and the devising of entirely new methods. Some attention should be given to the use of statistics in connection with analysis and to the meaning of precision and accuracy for a particular method. For a research problem to he used to prepare a thesis for an advanced degree, some analytical need, technique, or instrument should he selected as the basis, and independence of thinking should he encouraged. The joint efforts of professor and student should he toward developing the ability of the student to conduct independent research. There are many occasions in industrial research work where no satisfactory analytical method exists to supply the information needed. This is particularly tme in organic reseirch where mixtures of similar compounds are frequently encountered. If properly organized, the research work should serve to test and utilize the fundamental knowledge learned in class and give the student the experience in drawing upon such information which he will need later in undertaking analytical research in industry. During the course of the research there should develop an expert knowledge of and skill in the operation of the technique or instrument. Most important, however, should be the ability to develop a research program, to interpret the results obtained, and to describe a d e quately in a report what the work has accomplished. In seminar work there should be assignments to review critically the literature on a particular type of analysis and if procedures available appear to he inadequate to suggest other lines of approach. Plans might be developed for handling the separation and determination of the constituents in a complex research product using the techniques of hoth chemistry and physics or the identification and determination of the constituents in an unknown commercial product. These plans may or may not be tested by actual laboratory work, as seems advisable.

It is during graduate study that specialization should CONCLUSION heein. It is honed that in the nrescntotion of thcnnderIn brief, then, the curriculum for training a prospecgraduate courses there has been woven in some evaluation of the contributions which each field is making to tive analytical chemist should develop the following: scientific knowledge so that the student will have the Intellectuel ability with s clear understanding of the basic necessary facts to permit him to choose a field of s p e principles involved in both chemical and physical analyses. cialization which will challenge his interest. , In the field Manipulative skill, first in the major standard techniques uaed

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in analysie and later, when time is available, in more specific and specialized techniques. Creative ability and originality in thinking so that the resultant analytical chemist will he able to undertake research in devising new approaches and new procedures when necessary and will not be restricted by conventional methods. Ability to make sensible interpretations of data and to express results clearly and concisely.

Instruments should be discussed from the point of view of the principles of design and operation, general uses, advantages, and disadvantages and not from the point of view of machine operation. Instruction should teach how to analyze a problem and to select the best approach, due consideration being given to the various techniques available. No opportunity for developing judgment should be lost.

We recommend that emphasis be placed on the following points:

With a fundamental training of this sort and with the many excellent reference books at his disposal together with the experience of his supervisor and associates t o draw upon, the analytical chemist should he in a position to undertake his career with the prospect of success and satisfaction.

Organic analysis should he given fully as much attention a s inorganic analysis. Leoture material and laboratory experiments should be designed to illustrate principles or to demonstrate techniques.