F. E. C. SCHEFFER H. S. VAN KLOOSTER Rensselaer Polytechnic Institute, Troy, New York
W I T H the retirement of Professor Scheffer on September 1, 1953, the pursuit of phase-mle studies in Holland comes, if not to a full stop, a t least to a temporary halt. I t is generally recognized that this branch of physical chemistry, which originated with Willard Gibbs in 1878, was first developed theoretically as well as experimentally by van der Waals, Bakhuis Roozeboom, van't Hoff, and van Laar. This field of research has been ably explored by several other Dutch scientists following these pioneers, notably by Schreinemakers, Smits, Aten, Biichner, Reinders, and, last but not least, by Scheffer. In late years other branches of chemical knowledge, such as colloid and nuclear chemistry, have forged ahead and have pushed the phase rule somewhat in the background, but as Professor Scheffer pointed out in a recent lecture, the phase rule remains indispensable for chemical and metallurgical engineers in solving numerous technical problems. It is interesting to note that the thermodynamical treatises of van der Waals, long out of print, have recently been translated into Russian. Moreover, experiments carried out in Soviet Russia at pressures of 10,000 atmospheres have led to remarkable
results of unmixing in the gas phase, and Scheffer confidently expects that active interest in phase-rule work is bound to revive. Frans Eppo Cornelis Scheffer was born in 1883 in Veendam, a small town in Groningen, the northernmost province of Holland. After the usual primary and secondary education in his home town he matriculated a t the municipal University of Amsterdam, where he studied chemistry under Bakhuis Roozeboom, physics under van der Waals, and mathematics under Korteweg. After Roozeboom's death in 1907 Scheffer obtained his Ph.D. degree in May, 1909, cum laude, with Roozeboom's successor, Smits, as his promotor, with a thesis on "Heterogeneous equilibria in dissociating compounds." Scheffer's appointment as chemistry teacher in a secondary school in Amsterdam enabled him to continue his studies in Smits' laboratory. His postdoctoral work, partly in cooperation with Smits, dealt with the effect of dissociation on the vapor pressure of solids, the allotropy of ammonium halides, gaseous equilibria, and three-phase equilibria in the binary system hydrogen sulfide-water. Scheffer's success as a competent teacher and his growing reputation as a
APRIL, 1954
promising scientist led to his appointment as professor of analytical chemistry a t the Technical University of Delft. He entered upon his academic career in 1917 with a public lecture on "The significance of physical chemistry for analytical chemists." He was fortunate in having as a senior colleague the noted analytical expert ter Meulen, with whom Scheffer wholeheartedly cooperated in the solution of pressing analytical prohlems. In 1920 Scheffer switched from analytical chemistry t o inorganic chemistry, which subject until then had been in the charge of Professor W. Reinders. This change enabled Reinders to devote his time exclusively to physical chemistry. The old laboratory a t the West Vest, which for many years served both Scheffer's and Reinders' needs, was replaced at the end of World War I1 by an up-to-date laboratory in the Juliana laan. A considerable number of doctoral theses (26 in all) have come out of Scheffer's laboratory in the 36 years (1917-53) of his professorship a t Delft. A glance a t the titles reveals the wide range of Scheffer's interests in theoretical as well as in practical problems. Among the latter we find equilibria in permutites, copper chloride as catalyst in the Deacon process, catalytic cyclization of aliphatic hydrocarbons, methane in water gas, physicochemical studies in the treatment of crude phosphates with nitric acid, and the scientific examination of pictures. This last-mentioned topic, which is treated fully in a booklet of the same title, written by Scheffer's pupil, A. M. de Wild, and published by Bell and Sons in London (1929), brought Scheffer'sname before the general public. He was appointed chemical consultant to a committee of art connoisseurs chosen to judge the authenticity of a painting, "The Laughing Cavalier," supposedly by Frans Hals. This involved the testing of microscopic quantities of dyes removed without injury to the painting and the use of X-rays. Scheffer carried out this assignment with incomparable skill and ingenuity and thus was able to prove conclusively that the disputed picture was not a genuine Hals but afairly recent imitation.
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Scheffer's phase-rule studies, carried out to a large extent in close cooperation with his pupils, cover a great variety of topics. With Smittenberg, Scheffer studied several binary systems, among others, hexane-water, hydrogen sulfide-water, and ethylene-water. Vapor pressure data were obtained for bromine, nitrogen tetroxide, phosphorus trioxide, and phosphorus pentoxide. With his pupil (and now colleague) Meyer, Scheffer investigated the dissociation of carbon monoxide, the equilibria of tin with water and with carbon dioxide, and the formation of carbides in the system metal-carbon-oxygen. Nickel carbide and its properties were the subject of two articles which appeared 25 years apart (1928 and 1953). Most of these papers appeared in the Recueil, in the Proceedings of the Royal Academy of Amsterdam, and in the Zeitschrift fur Physikalische Chemie. A few of Scheffer's postwar publications were published in American journals and thus attained a larger circulation. These last-mentioned researches deal with the remarkably high solubility of slightly volatile naphthalene and hexachloroethane a t high temperatures and pressures (up to 270 atmospheres) in supercritical ethylene. For the benefit of his own students and for Dutch chemists in general Scheffer has written two brief texts, both published by Waltman in Delft, one on "Applications of Thermodynamics to Chemical Processes" and more recently, "Heterogeneous Equilibria in Unary and Binary Systems." Scheffer is a member of the Dutch Royal Academy of Sciences and holds an honorary degree from the University of Ghent. Now that he has retired from teaching and research, it is hoped that Professor Scheffer,still hale and hearty a t 70, may find the time to condense the accumulated wisdom of 40 years of research in a text suitable for postgraduate students in English-speaking countries. No finer tribute could he paid to the memory of the great protagonist of the phase rule by one of his last survivingpupils in this year of 1954, which marks the centenary of the birth of Bakhuis Roozeboom.
