The Pains and Pleasures of Industrial Analytical Chemistry - Analytical

ANACHEM AWARD ADDRESS

The Pains and Pleasures of The personal reminiscences of Dr. Stenger as related in his Anachem Award Address, October 15, 1970, provide interesting insight into the sort of problems that challenge industrial analytical chemists. The contributions of the analytical chemist are essentia] in many areas of industry.

Tfold.

HE PURPOSE OF T H I S PAPER IS t w O -

First, I should like to show students of chemistry t h a t in dustrial analysis is not necessarily a routine, boring occupation. I t can be frustrating at times, but it can also be fascinating, instructive, hu morous, and even exciting. I t is usually pleasant, and it is always worthwhile if one dedicates himself to learning about what goes on in chemical systems. I n this usage, perhaps, the term "chemical sys t e m s " m a y also include people. Secondly, I hope to encourage every analytical chemist as to the value of his or her individual efforts. T h e key to enjoying analytical work lies in knowing t h a t the results will be useful and important. I n industrial chemical analysis there are pleasures to bo enjoyed, and pains both to be t a k e n and to be suffered. Hence, the title of the paper. I t might have been " T h i r t y five Years of Industrial Analytical Chemistry," but nobody would want to hear or read something of t h a t duration. In any case, it is nec essary to draw from personal expe riences to illustrate my points. One of the great pleasures of 36 A ·

being an analytical chemist is t h a t of being able to associate with ex ceptionally fine people. We have many in our own organization, our competitors and customers have others, and, of course, there are m a n y in government labs and in the universities. For a person working in an industrial laboratory the op portunities for outside contacts are greatly increased by activity in technical organizations. I t has been my privilege to work with the ACS Committee on Analytical Reagents and also to work earlier with the A S T M Committee on Chemical Analysis of Metals. Memories of the distinguished chemists who be came my friends in those groups will always be treasured. The list would start with G. E. F . Lundell, W. D . Collins, and E d w a r d Wichers, and would include m a n y of the pre vious Anachem Award winners. Through the Analytical Division of the ACS I encountered m a n y others. One of these was Ν . Η . F u r m a n of Princeton University. H e had translated the first German edition of Kolthoff's "Volumetric Analysis," so we could commiserate on the diffi culty of trying to keep Professor

ANALYTICAL CHEMISTRY, VOL. 43, NO. 3, MARCH 1971

Kolthoff satisfied with our slow progress. I got a real lift from F u r man's confession t h a t whenever he spent an evening with the Saturday Evening Post, he felt guilty know ing that, in the meantime, Kolthoff had probably written three papers.

Initial Challenges

When I first came to the Dow Chemical Co. at Midland, Mich., it was my intention to gain a year of industrial experience and later go into teaching. Several things h a p pened that first year to change my mind. A number of us were hired at about the same time, and the company, still a fairly small organi zation, arranged for us to tour some of the operating plants and to hear a few lectures on what was being done. I n one of the lectures, I v a n Harlow, then chief chemist, spoke about the composition of brines oc curring in different geological strata beneath Midland. I t was quite in teresting to learn t h a t the brines varied in their bromine contents, and also t h a t one could identify the source, independent of dilution, by determining the ratio of calcium to

REPORT FOR ANALYTICAL CHEMISTS VERNON A. STENGER Analytical Laboratories, The Dow Chemical Co., Midland, Mich. 48640

Industrial Analytical Chemistry magnesium. Previously I had been interested in rock analysis and had not thought much about brines. Later that year I visited a wellknown university to apply for a teaching position. During the interview I told the professor about those Midland brines. He did not seem impressed and I did not get the appointment, but he did me quite a favor by asking a simple question which I could not answer. He wanted to know how much fluoride was present in any of the brines. I still do not have an exact answer, but there is less fluoride than we can detect by any sensitive method tried. The reason I appreciated the question is that it opened my eyes to the possibility of learning much more about brines than I then knew, and it gave me an added interest in trace analysis. Subsequently, in about 1938, the company drilled into a deeper stratum yielding brine with a higher bromine content. Walter Kramer and I carried out the first complete analysis of this brine and discovered that it contained about 40 ppm of iodine. Others at Dow developed a process for recovering the iodine, and as a result, Michigan has become the leading state for iodine production in the U. S. We found significant concentrations of strontium and lithium in the brine, too. Later, Robert Goodenough, working in our group, developed processes for the recovery of those elements. The processes have not been used commercially but they are available in case a demand should arise. Need-

less to say, one of the pleasures of my career has been the opportunity to participate in developments such as these. During that same first year Willard Dow sent a man over to the laboratory who said he could extract gold from sand. The sand could be taken from a river bank, or almost anyplace. A. W. Beshgetoor, our lab director, asked me to look over the process with him. The man had a big iron bowl, rather flat but rounded, into which he would put the sand, some water, and a little mercury. After stirring the mixture, he would pour off the sand and water, and the mercury remained as a surface layer on the iron. With a rubber spatula he would scrape off the mercury, dissolve it in nitric acid, and end up with a small golden crystal in the acid. We sent a crystal to a spectroscopist, who soon reported back that it was, indeed, gold. Meanwhile, we found that the metal would dissolve only in aqua regia, and that it would give the Cassius purple test. Obviously the man was showing us gold, but was it actually coming from the sand? Mr. Beshgetoor took him out to lunch, and while they were gone I operated the process a little myself. First I found that sand was not necessary. Just putting mercury and water in the bowl would produce gold. Then I found that the bowl, water, and spatula were not necessary either. Our man was using mercury which contained just enough gold to be interesting. When they returned

from lunch I reported my findings, much to Mr. Beshgetoor's enjoyment. The promoter packed up his equipment and left, saying, "Here I have a valuable discovery, and you chemists are just too damned skeptical to appreciate it!" The incident made me wonder why a capable executive like Dr. Dow would allow such a fellow to take up our time. I may have speculated also that chemical company management might occasionally need the aid of a chemist to screen out bad proposals from good ones. Back in Minneapolis I had sought a job with a paper mill, and had been told that they could afford a chemist only in periods of great prosperity. Be that as it may, the gold affair also taught me that an analytical chemist should not be content with carrying out a qualitative or quantitative analysis alone, but should look at the whole problem. Later I had an opportunity to talk with Dr. Dow about the incident. He said that the man had been a company customer, but had evidently taken on some new partners who had involved him in this shady deal. I said, "Then you did know all the time that it was probably a fake?" H e laughingly replied, "Yes, but wasn't it fascinating?"

Problem-Solving in Analytical Chemistry

The point about an analytical chemist looking at the whole problem can stand some belaboring; Dr. Laitinen editorialized upon it rather gently in the September 1970 issue

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ANALYTICAL

CHEMISTRY.

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points were t h a t an analytical chemist should know enough about existing methodologies to choose the best one for application to a given sample, perhaps modifying it if nec essary to fit the particular situation, and t h a t there is also an analytical science which seeks, as its own goal, the improvement of analytical methodologies without regard to specific problems. Years ago, D r . Lundell wrote about the " a n a l y s t s " and the "determinators." T h e ana lysts were those who could t a k e a sample as it was, apply suitable methods allowing for interferences, and come up with a correct anal ysis. T h e determinators were those who preferred to develop methods for single substances. T h e y generally worked with pure solutions and were not concerned about interferences. Nowadays, with more and more instrumental methods in vogue, the analysts and determinators are coming closer to gether. Some m a y only be syringehandlers, button-pushers, or turn table-feeders; the interferences are supposed to be t a k e n care of auto matically. Before a determinator can use an automatic system, howover, a good analytical chemist has probably been needed to set it up, perhaps with the aid of a computer export. ΐ like to think of an industrial analytical chemist taking on a whole problem, in the following sense: A product is found to de part from specifications in some way, perhaps showing an off-color, turbidity, or low melting point, or possibly a foreign peak in a spec trum or chrornatogram. T h e first finest ions for the chemist are: what is it, and how much? For the pro duction supervisor, though, the questions a r e : how docs it get in, and how can it be kept out or re moved? T h e complete answer re quires characterization, measure ment, some chemical detective work, and a knowledge of the physi cal and chemical properties of the impurity and of the rest of the sys tem. T h a t the answer be reached promptly is usually quite urgent; to produce bad material is uneconomi cal, and to shut a plant down is al most unthinkable. Problems of this kind can be p r e t t y demanding. The

analytical chemists who can handle them will be treated with respect. I am concerned t h a t chemistry students these days m a y be led to rely too much upon instruments, without learning enough about classical separation methods and the descriptive chemistry that should be taught in analytical courses. These kinds of knowledge are needed to solve our chemical problems. We should face this fact in our technical organizations and in our dealings with colleges and uni versities. There is an old saying: To be a good chemist one must first be a good analytical chemist. T h e converse m a y be even more true—to be a good analytical chemist one must first be a good chemist. We can teach instrumental analysis in industry, but we should not have to teach basic chemistry. Neverthe less, we all must continue to be stu dents of chemistry. Contributions in Product Development

I t should not be thought t h a t in dustrial chemical analysis deals only with quality control. Often the problem is with the use of a product. Years ago I was asked to participate in the early develop ment of methyl bromide as a fumigant. M e t h y l bromide was a new and mysterious compound, volatile and quite toxic, and people were afraid to use it. Air. Beshgetoor m a y have selected me for the as signment thinking t h a t I was ex pendable. Questions arose as to how to determine whether, during a fumigation, the vapor would re main in a vault or warehouse long enough to be lethal to insects, whether it might poison someone outside, and how much might re main as a residue in a fumigated food. S. A. Shrader, M r . Besh getoor, and I developed methods for use in answering such questions, and published them. T h e necessary toxicological d a t a were determined in the Biochemical Research L a b oratory established somewhat earlier under D o n Irish. One of my pleasures during t h a t period con sisted in receiving supplies of fine fresh foodstuffs, fumigating them, and preparing samples after peri ods of airing. I would carry out separations of the organic and in organic bromide, and D r . Shrader

would determine the bromide in each fraction using Kolthoff and Yutzy's modification of the v a n der Meulen method. We established t h a t practically any food would lose all of its methyl bromide within two days and t h a t only a trace q u a n t i t y of inorganic bromide would remain. F o r a given food, the amount of inorganic bromide remaining would be fairly propor tional to the concentration of fumigant and the duration of exposure. Incidentally, we could also carry home a fair amount of the food. T h e Stengers and Shraders ate un usually well in those days. At one time we had over 100 lb of fine Wisconsin cheese in the lab. Among other foods tested were hams, dehydrated vegetables, cere als, bakery products, butter, ice cream, chocolate, various kinds of nuts, etc. Thus, we established, not only by analyses, but by practical eating tests, t h a t the foods were suitable for consumption. We, and others, recognized a problem in the fumigation of wheat flour: if an excessive concentration of methyl bromide were used, or if the same flour were fumigated repeatedly, a bad odor might be produced when it was baked into bread or when the bread was toasted. The odor was eventually attributed to the methylation of sulfhydryl groups in the protein, releasing a trace of methyl mercaptan or thio-ether upon heating. W e got to be pretty good at recognizing such odors in complaint samples, and could con firm the cause, when it was overfumigation, by determining the bro mide residue. M y wife took part in this kind of work at home, bak ing the flour into bread or rolls which we tasted and smclled. Most commercial millers are highly re liable and when presented with our data would accept the fact that the flour had been overexposed. There were a few small outfits, however, t h a t tried to blame fumigation for problems caused by old or moldy wheat. Our testing program thus saved the company considerable money in the early days. I t has been continued as a service to fumigators, but whereas we used to de termine bromides chemically, now they are done by X - r a y fluorescence or bv neutron activation, with a


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Report for Analytical Chemists saving in time. However, in case of question, we would still rely on the old chemical method. In one case there was a fatal accident during the fumigation of a flour mill. Two of the fumigators died from methyl bromide exposure and it was later established t h a t they had failed to replace their gas mask canisters following previous fumigations. The charcoal had become saturated with methyl bromide. Nothing could be done for the men, but the milling company was in trouble. A city toxicologist had decided t h a t if methyl bromide killed the men it must also have poisoned the tremendous amount of flour stored in the warehouse. Therefore, he ordered an embargo on shipments. D o w was notified and asked to provide technical assistance. Oscar Daniels and I worked all afternoon getting laboratory equipment packed and preparing bromide-free hydrochloric acid to be used in analysis of the flour. Then, with some other company representatives, we drove most of the night to reach the site of the accident. P a r t of the evening was taken up at the Canadian border, trying to help customs officials classify our lab apparatus properly; a threatened crisis there was solved by the decision t h a t nickel crucibles, used for alkalineashing of the flour, could be classified as kitchenware. After less t h a n three hours of sleep, we went to work analyzing the flour, at 8 A.M. Fortunately some F D A men had been called in and they were acquainted with our paper on residue determinations. On t h a t basis, they agreed t h a t if the residues did not exceed what we felt to be reasonable for an ordinary fumigation, the flour could be released. This was my first experience demonstrating t h a t a publication might have tangible value. The millers furnished us with samples of flour t a k e n from freight cars t h a t had already been loaded. As we turned out the bromide results and the data were favorable, the car would be hauled away. A vice president of the milling company stood by, and his spirits rose visibly as each car rolled out. We kept working right through until 2 A.M. the next morning, and he stayed

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with us until the last car was gone. I have seldom seen anyone more appreciative. Ever since then, our company has enjoyed an excellent relationship with his. Work with Rare Earths

Another pleasure to be enjoyed by an industrial chemist is a very simple one, t h a t of working with chemicals. T h e larger the company, the greater is the chance of encountering a wide variety of the less common elements and compounds. When alloys of magnesium and the rare earth elements were being studied, our group did much of the analytical work. We began by running total rare earths as oxalates, with ignition to oxides. Different sources of the rare earths were used, so that the individual elements varied in concentration. If I had to do one kind of routine analysis for the rest of my life, it would involve, preferably, the precipitation and filtration of rare earth oxalates. While the precipitates rest in the filter paper they show such beautifully delicate shades of light violet or green, according to the relative amounts of neodymium or praseodymium present. As the work progressed we added a determination of cerium volumctrically, then colorimetric methods for neodymium and praseodymium. Finally, Warren Crummett added spectrophotom e t r y determinations of other elements, applying ultraviolet methods pioneered by H . E. Kremers of the Lindsay Light and Chemical Co. Later a sebacate precipitation was introduced by Wengert, Walker, and Loucks to give more complete recoveries of the rare earths and to allow separations from zirconium and thorium. We might have profited from flame photometry and atomic absorbance in those days, had they been available. Eventually, X - r a y fluorescence proved to be of great value, and now, activation analysis is showing tremendous sensitivity for some of the elements. M y points are, it was a pleasure to run these analyses and to see how the results could be correlated with the properties of the alloys, it was a challenging task to modify and expand the methods, and it is still

Report for Analytical Chemists

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gratifying to learn how newer techniques can be applied. Pains of Failures and Need for Reliable Data

What about the pains of industrial chemical analysis? There are, to be sure, the actual headaches of the job while a problem remains unsolved, but these arise from its urgency and excitement, and later become subjects of our reminiscences. All good vocations should have some headaches. A more real and undesirable pain is that which comes from failure to do a job correctly. In one of my early assignments, I was given a sample of calcium chloride from an electrolytic cell in which a researcher was trying to prepare calcium metal. The sample contained a dark sludge which interfered seriously with the electrolysis. I diagnosed the sludge as carbon, and thought that a sufficient proof consisted in rinsing and drying it, then igniting to get rid of the combustible part. Only a white residue, high in calcium, remained. The researcher tried to eliminate carbon from the system, but he always produced the sludge, and finally he gave up. Several years later I learned about the effect of boron on the electrolysis of magnesium, and the fact that calcium chloride from brine usually contains some borate impurity. Then I realized that by not actually proving the presence of carbon, and by failing to consider any other element, I had almost single-handedly kept the company out of the calcium business. This may not have been too bad, for an economic evaluator might have done the same with even less evidence, but it was no excuse. The job was done poorly and the memory is painful. The suffering of pains of that kind can be avoided by taking the proper pains in one's work. Analytical chemists have always been concerned with accuracy. More and more they must become concerned with completeness of analyses and with the total reliability of conclusions, especially in respect to the systems involved in ecology. Traces of substances once thought harmless are now seen to cause problems. Other substances may be blamed, somewhat unjustly, as pol-

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lutants ; for example, phosphate detergents have taken a beating which a few people, including myself, think should have been administered to organic materials in sewage. Trichlorophenoxy acetic acid (2,4,5-T) and related compounds have been threatened with banishment as herbicides because of reported teratogenic effects on animals. These effects were not caused by the 2,4,5-T, but by an impurity present in the sample that was tested. The active impurity has been identified as a tetrachlorodiphenyldioxin; for a number of years its presence has been held below safe limits by those manufacturers who earlier recognized that the impurity could cause trouble. AVith pure 2,4,5-T, there is no problem. Another frequently maligned compound is DDT. The presence of D D T has been reported in almost every important living species. However, the gas chromatographic method frequently used for DDT determination has been classed as unacceptable by E. F. McFarren et al. who reported in the March 1970 issue of ANALYTICAL CHEMISTRY [ANAL. CHEM. 42, 358 (1970) ]. I do

not doubt that D D T is a threat to the environment if used improperly or too widely, but it would certainly be desirable to have all judgments made on the basis of completely reliable data. To get at the truth, conscientious analytical chemists, toxicologists, and biochemists must work together. One cannot say enough about the importance of the analytical chemists' contribution. Without it, the others can be completely misled. Mercury?—Questions and Answers

Some of you may be interested in the question of mercury and its determination in the environment. This is a fascinating question with many aspects. It illustrates, again, the importance of analytical chemists looking at the whole picture. Gunnel Westôô in Sweden had developed a gas chromatographic method for the determination of alkyl and aryl mercuric compounds extracted from fish with benzene and dilute hydrochloric acid. She \vas interested in those compounds because of their use as slimicides, but it turned out that regardless of 42 A

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what compound was used, the mercury found in fish was present as a monomethylmercuric ion. The determination of mercury in foods in this country generally was being done by the dithizone method, but the digestion procedure used in the analysis would not convert methyl mercury completely to inorganic form, so low results were being obtained on fish. When the discovery of mercury in Great Lakes fish was made by Norvald Fimreite at the University of Western Ontario, it was done by neutron activation analysis. Chemists at the laboratories of Dow Chemical of Canada quickly recognized the importance of using an adequate digestion treatment prior to other types of analysis. They modified a procedure (previously used by others) so that it would give complete recoveries of alkyl mercury. This procedure was then employed in connection with the so-called flameless atomic absorbance method, in which the ultraviolet absorbance of mercury vapor is determined. Cross checks of their procedure between laboratories, and with the neutron activation method, have shown good agreement in analytical results for mercury, both in fish and in bottom sediments. A number of questions about the behavior of mercury remain to be answered. Several theories have been proposed as to how mercury might go from inorganic form in water or a bottom sediment, into methylated form in a fish. One theory assumes anaerobic conversion in the mud to volatile dimethyl mercury which enters fish via the gills. Another assumes aerobic conversion to monomethyl mercury by bacteria, with subsequent transfer up the food chain. Still another assumes that a fish itself can methylate mercury taken in either through the gills as elemental vapor, or via the stomach as inorganic ions, or in an adsorbed state on silt particles. There is some evidence for each mechanism. It is desirable to learn which is more important, to know what kinds of methods might be most fruitful for alleviating the situation. Before all the questions can be answered, we need to develop highly sensitive methods for each individual form of mer-


cury. At present the most sensitive methods can go down only to about 0.05 ppb inorganic mercury in water. At the conference on Environmental Mercury Contamination held in Ann Arbor, Mich., in early October 1970, a number of sources from which mercury may enter the environment were mentioned. Among them, in addition to losses from some segments of the chloroalkali industry, were the burning of fossil fuels, use of mercurial compounds for slimicides in paper mills and for fungicides both in paints and in agricultural seed treatments, use of elemental mercury in the electrical industry for manufacture of batteries and mercury vapor lamps, use of mercuric catalysts, and the disposal of domestic sewage sludges. It will be up to analytical chemists to evaluate all of the sources and to provide the data on which proper action can be based. This will be true not only for mercury, but for all environmental contaminants. Analytical chemists, especially those in industry, are going to be busy for a long time. It is interesting that both Finnish and Swedish chemists have found fairly high mercury contents in fish from certain lakes in northern parts of their countries, remote from any known source of pollution. We have encountered some similar cases in northern Michigan and Ontario, and Canadian authorities have found several in various parts of Canada, including Hudson's Bay. The possibility of geological origin remains to be investigated. Another interesting fact is that mercury will be found in the hair of a person who has been exposed to it. The average person has about one or two ppm in his hair. J. K. Miettinen of the University of Helsinki, Finland, has made a thorough study of data from his own country, Sweden, and Japan. No symptoms of mercury poisoning have been found in any subject whose hair contains less than 60 ppm. R. E. Jervis of the University of Toronto has reported 150 ppm as an upper safe limit. With more than these amounts, a subject may or may not show symptoms, depending, perhaps, upon differences be-


tween individuals as well as upon differences between their exposures. It seems likely that a few severe exposures might produce a greater effect than many very small dosages because the body can more easily handle the smaller quantities. One of the victims in a New Mexico case last winter showed 2500 ppm mercury in the hair. People who have had mild occupational exposures may show from 10 to 30 ppm. By analyzing sections of the hair of a long-haired person and knowing its growth rate, one can approximate the time and intensity of exposure. Most of these analyses have been done by neutron activation, which is advantageous because very small samples can be employed. However, hair can also be analyzed by the atomic absorbance method following the digestion procedure used for fish analysis. A 100-mg sample is sufficient for hair in the range of 1 to 10 ppm. Economic Pains

I would be remiss if I neglected to recognize the pains that can be felt in an industrial environment during times of economic readjustment. No doubt similar situations occur in government and in academic or institutional life, but industries are likely to react more swiftly. In my experience, management people, especially lab management, do not like these situations any more than do the victims. Also, I believe, that during a period of reorganization, the best chemists, being the most sensitive individuals, usually suffer more mentally than do the poorer ones who may have too high opinions of their own abilities. The good chemist knows he has some weaknesses and can easily see why he might be released. Others may not have such worries. A change is not necessarily bad for the individual, however. At one time when Mr. Beshgetoor and I had to release some people, they took it well and later we were happy to learn that they had found better positions elsewhere. Professional Pride

The final pain that should be mentioned is one which analytical chemists bring on themselves. Because many chemists and some en-

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(13),

50A,

(1969) ] pointing out t h a t we should take pride in w h a t we do, t h a t we are indispensable, a n d t h a t we should feel indispensable. T h e sad fact is t h a t we are not always so confident, and people in other pro fessions can sense this. T o illus t r a t e : I once h a d t o visit a custo mer on a complaint problem where we faced a possible lawsuit. One of our lawyers cautioned me before I left as to what I should do if the customer brought u p the question of a financial settlement. H i s sugges tion was to say, " I am only a chem ist. If y o u w a n t t o talk about money, you will have to t a l k with our lawyers." A t the time I h a d no reply to that, b u t after years of thinking about it, I can now advise on what to say in a similar situa tion. I t is: "Sir, I am a chemist. I a m here to help you technically in every way I can. However, if you insist on talking about money, you will have t o t a l k with some one who is only a lawyer or a n accountant." I n subsequent experiences with lawyers I have had to educate them in technical matters t o a t least as great an extent as they have had to train me concerning the law. Our professions should be on an equal footing, except t h a t whereas we are always seeking t h e truth, there arc lawyers who sometimes seek to ob scure it. Charles M a n n , late pro fessor of chemical engineering a t Minnesota, handled the matter well in an anecdote he once related a t a student gathering. H e was serving as an expert witness in a lawsuit and t h e opposing attorney w a s browbeating him during cross-ex amination, but was unable to shake an opinion which D r . M a n n h a d given in testimony. Finally, in ex asperation, t h e lawyer said, " B y what right do you express such a n opinion?" D r . M a n n looked t h e lawyer in the eye and replied, " B y the right of being a scientist!" H i s side won t h e case.


44 A · ANALYTICAL CHEMISTRY, VOL. 43, NO. 3, MARCH 1971

We base our opinons a n d con clusions on solid experimental grounds. W e are scientists, and we have all t h e rights a n d privileges t h a t go with t h a t estate. W e a r e working in the branch of chemistry t h a t h a s t h e largest number of members in the American Chemical Society. T h e results which we ob tain a r e needed. Our work is in teresting, honorable, a n d useful. We can be, and should be, proud of our profession. T o summarize, there a r e both pains a n d pleasures in industrial analytical chemistry. I feel t h a t the pleasures we enjoy far outweigh any pains t h a t we have to suffer. The pains t h a t we take a r c mea sures of our professional ability, and the means whereby wc can render the greatest service to society.

Vernon A. Stenger, analytical scien tist with The Dow Chemical Co., Midland, Mich,, received his B.S. in chemical engineering and M.S. in chemistry from the University of Denver in 1929 and 1930, respec tively. He earned his Ph.D. degree under I. M. Kolthoff at the Univer sity of Minnesota in 1933. He has been with Dow in Midland since 1935. He was honored at Detroit by receiving the Detroit Anachem Award in 1970 for his outstanding contributions to analytical chem istry through research, administra tion, and other activities advancing this division of chemistry as a pro fession. Dr. Stenger is a member of the ACS and has served on the Advisory

Board

CHEMISTRY.

of

ANALYTICAL

The Pains and Pleasures of Industrial Analytical Chemistry - Analytical

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