(b. Rétság, Hungary, 20 April 1901; d. Budapest, Hungary, 23 January 1944)
Szebellédy was the son of Ferenc Szebellédy, a pharmacist, and Maria Pohl. He earned a degree in pharmacy at the University of Budapest in 1923, but instead of becoming a pharmacist he turned to scientific research. In 1925 he was named assistant to Lajos Winkler at the Inorganic Chemistry Institute of the University of Budapest. An outstanding analytical chemist, Winkler had become famous for his methods of determining the amount of oxygen dissolved in water (1888) and the iodine-bromine number of fats for his work in precision gravimetry, and for his books. Szebellédy collaborated in Winkler’s analytical research. His first independent publications (1929) dealt with the classical methods of analysis. He later spent considerable time away from Budapest working with foreign scientists, notably Wilhelm Böttger at Leipzig and William Treadwell at Zurich. In 1934 Szebellédy qualified as a lecturer in analytical chemistry at the University of Budapest, and in 1939 he was appointed professor of inorganic and analytical chemistry. The extensive program of research that he subsequently undertook was prematurely halted by his death from cancer.
Among the topics that Szebellédy investigated was catalytic ultramicroreactions, introduced into analytical chemistry by I. M. Kolthoff and E. B. Sandell for cases in which it is possible to obtain an accurately measurable endpoint (1937). Most catalytic color reactions, however, proceed continuously. Working with Miklós Ajtai, Szebellédy devised the analytical application for this type of reaction (1939). With the assistance of his young co-worker Zoltán Somogyi (whose death during an air raid preceded his own), Szebellédy invented the coulometric titration method (1938), which is widely used in analytical chemistry.
Szebellédy’s paper on coulometric titration is “Die coulometrische Analyse als Präzisionsmethode”, in Zeitschrift für analytische Chemie, 112 (1938), 3137ndash;336, written with Z. Somogyi; and that on catalytic analysis is “Die quantitative Bestimmung von Vanadin mittels aktivierter Katalyse”, in Mikrochemie, 26 (1939), 87–94, written with M. Ajtai.
A secondary source is F. Szabadváry, History of Analytical Chemistry (Oxford, 1966), 190, 316, 317.