International Congress on Analytical Chemistry A. H. W. ATEN, Hilversum, Netherlands
A
N INTERNATIONAL congress on analytical chemistry was
of the regulations for sampling sugar in bags, which is imported into the United States. A4ninteresting example showed how statistical treatment may discover inaccuracies in analytical proce dures. W.J. Gooderham (London) gave a most impressive demonstration of a new method for gas analysis, depending on volumetric measurements using soap membranes moving through gas pipets. The entire analysis of illuminating gas is carried out in a single train of absorbers. Reports by Pieters and Schmidt and by Forbes dealt with standardization of analytical methods, one by Degens with the task of the analytical chemist in industry, and one bv Boeke with the economic aspects of the rationalization of analysis. Aten junior had submitted a paper on the use of isotopic tracers in analytical chemistry, Kistemaker one on the mass spectrometer and some of its analytical applications, Gouverneur a paper on organic elemental analysis, and Deinum and Dam one about a modified Orsat apparatus for the analysis of purified c o k e oven gas. In the section for electrical methods E. Leclerc (LiBge) spoke about electrical methods for analysis in industry. Speed, sensitivity, and precision of electrical measurement techniques were discussed. Application of these methods in metallurgy, in the oil industry, and in water purification was mentioned. The same techniques are useful in some types of organic analysis, as in the determinations of vitamins. Application to the detection of rare elements in fertilizers may also be considered. Among the reports offered were two on water analysis, by Bijker and Janssen. Claassen described a continuous reading vacuum tube voltmeter for electrometric titrations. Lingane had written about controlled-potential electroanalysis and Kolthoff about amperometric titrations. dpplications of the polarographic method to the determination of alkali metals, calcium, barium, aluminum, lead, and zinc in glass and of lead, cadmium, and zinc in metals and in ores were treated by Vandenbosch and by Favre. In the spectrographic section the main lecture was delivered by E. Loeuille (Paris), who presented a very extensive treatment of the construction of prism spectrographs, the use of photographic plates, and the principles of qualitative and quantitative spectrographic analysis. Inaccuracies in current wave-length tables were reported. The methods of Gerlach and of Kayser for the analysis of alloys were discussed critically. The use of a hyperbolic rotating sector was mentioned. Milbourn had submitted a paper on factors affecting the accuracy of spectrographic analysis and D. M. Smith with G. N. Wiggins had written about improvements in the technique of spectrographic analysis of high purity materials. Spectrographic analysis after preliminary concentration was the subject of communications by R. L. llitchell with R. 0. Scott and by Sempels. Castro with Phbline described the determination of aluminum, and Herman the determination of columbium and tantalum. J. Orsag dealt with the determination of sodium in aluminum. In the fourth section G. Duyckaerts (LiBge) spoke about absorption spectra and their analytical applications. He gave many examples of chromophoric groups and stressed the necessitv of collecting extensive data on absorption spectra for analytical purposes. He mentioned the sensitivity of absorption spectra to traces of many impurities. Thus 0.1% of cyclohexanone in cyclohevane gives rise to a characteristic band. Special attention is given to the important problem of deviations from Beer’s law Molecular changes or molecular interactions may play a part: theoretically the absorption must vary with the refractive index of the mivture and-most important of all-deviations are to be expected if the wave-length band used is wider than the absorption band. For this reason use of interference filters is desirable.
heldat Utrecht (Netherlands)on June 1 , 2 , and 3,1948, under the auspices of the Netherlands Chemical Society and with the support of the Dutch chemical industry. The purpose of this congress was to provide information for industrial chemists about recent analytical developments, an aim which was facilitated by ample opportunities for personal contacts during these days. Special attention was given to the organization of analytical work in industrial laboratories and to the training of analytical chem-
ists. Approximately 350 people were present, among whom about 90 had come from other countries in Western Europe. Great Britain was represented by some 40 visitors. It mas much regretted that no participants from the United States attended. I. M. Kolthoff of Minneapolis and J. J. Lingane of Harvard University had submitted reports, which were very much appreciated and were discussed with a great deal of interest. The congress was seriously disappointed by the fact that J. Heyrovskf of Prague, who had promised to lecture about nex developments in polarography, had been refused permission to leave Czechoslovakia by the new government. Apart from a few general speeches, the activities of the congress were divided over the following five sections: General Methods and Normalization, Electrical Methods, Emission Spectrography, Optical Methods and Physical Methods of Separation, and Microbiological Methods and Detection of Traces. In each section one or two lectures were given by invited speakers from outside Holland. After those a number of reports were discussed. These papers had been sent to the members of the congress as preprints, and it was assumed that everybody present was already familiar with them. After the rector of the university and the president of the Netherlands Chemical Society had both spoken a few words of welcome and after a telegram from the Australian Microchemical Society had been read, C. J. van Nieuwenburg, professor of analytical chemistry a t the Delft Institute of Technology and president of congress, delivered the opening speech. He described the development of analytical chemistry and traced its borders. Special attention was paid to the difference between analytical chemistry as a science and chemical analysis as a routine technique. I n the course of the congress several general lectures were given, the first of which by G. Charlot (Paris) dealt with the duties of the present-day analytical engineer.. The necessity was stressed of adapting analytical procedures to the ability of unskilled per~onnel. Application of chemical theory is very profitable, as illustrated by the separation of columbium from tantalum and by the use of silver in the presence of chloride ion and of gold in cyanide solution as reducing agents. The time reserved for the lecture of Heyrovskf was filled by Professor Duval (Paris) , who spoke about analysis of mixtures by decomposition. A special apparatus, a “thermobalance,” was described, by which niivtures of calcium and magnesium are analyzed by decomposition of the oxalates and copper-silver mixtures by decomposition of the nitrates. In the final session H. W.Thompson (Oxford) delivered an enthusiastic lecture on the use of infrared spectrography. Technical improvements involving synthetic crystals were discussed and beautiful results n-ere shown, which had been obtained in the analysis of organic compounds. Everybody regretted that time did not permit the speaker to continue with a review of applications of Ranian spectrography. In the first section E. C. Wood (London) lectured on recent applications of statistics to chemical analysis. Expert advice by statisticians mav often save enormous expense. Thus a detailed mathematical study was the cause of an important simplification
994
99s
V O L U M E 20, NO. 10, O C T O B E R 1 9 4 8
T. I. Williams (London) lectured on recent developments and future possibilities in the field of chromatogaphy. Paper chromatography and partition chromatography were described in detail. The analysis of mixtures of amino acids was illustrated by several examples. Work done in recent years on the separation of rare earths in ion-exchange columns was reviewed. Remarks about theory of chromatographic processes concluded the lecture. Papers dealing with colorimetric absprption analysis, with Raman spectrum analysis, and with infrared spectrography were submitted by Coumon, by Duyckaerts and Michel, and by La Lau. Karsten, Rademaker, and Walraven described a colorimetric copper determination by means of sodium diethyldithiocarbamate, and Pieters and Hanssen the spectrophotometric determination of traces of oxygen in water. Verheus, Smit, and ICramers with Broeder had written about analytical applications of rectifying distillation, of adsorptive percolation, and of thermal diffusion. I n the last section G. Bertrand (Paris) spoke about the difficulties encountered in the determination of trace elements in biological materials. The difficult problem of ashing without loss of sulfur, halogens, or phosphorus was discussed. As large quantities of reagents are usually required, the danger of mistakes due to impure chemicals is very serious indeed. Difficulties may often be avoided by the use of gases as reagents, but it is necessary to filter the gases through long tubes filled with cotton. In the case of arsenic the danger of contamination is exceedingly serious.
W. F. J. Cuthbertson lectured on the technique of vitamin assays and on the use of microorganisms for analytical p u r p o s ~ . Rameau, Reith, and Deys had written about the determination of lead in plant material, Hoogland about the determination of aluminum, arsenic, boron, copper, fluorine, iron, manganese, magnesium, and zinc in teeth and in cereals. The separation of free choline from “combined, water-soluble” choline by adsorption on silica was described by Dusset. Van Voorst presented a complete system for the quantitative analysis of mixtures of fructose, glucose, saccharose, lactose, maltose, and reducing and nonreducing dextrin by a combination of chemical and biochemical methods. Ilstra described a microbiological technique for the determination of tryptophan. Mulder presented a note about the microbiological estimation of copper, magnesium, and molybdonum in soil and plant material. Van der Linden dealt with the determination of several organic compounds by using lactic acid bacteria. Gerretsen described the use of Aspergillus niger for the determination of plant nutrients in soil. The different speeches were summarized by P. E. Wenger (GenBve) and the congress was closed ith a speech by the president. During the congress a new nonrecording ultraviolet spectrophotometer by Hilger was demonstrated. All the papers and notes presented will be published in the Analytica Chimica Acta, except those of section 3, which will appear in Spectrochimica Acta.
Instrumental Methods of Chemical Analysis
Instruments, Techniques, and Applications of Radioactive Isotopes. BENJAMIN SCHLOSS, Nucleonics Sales Co., New York, N. Y.
York Section of the AMERICAN CHEMICAL SOCIETY Thas New planned an all-day Symposium on Instrumental Methods HE
of Chemical Analysis, a t Washington Square College, S e w York University, on Kovember 20. The meeting will be held in the auditorium of the School of Education building a t Fourth and Greene Sts., beginning a t 9: 15 A.nr. Ralph H. l f uller, S e w York University, will preside, and following introductory remarks by C. s. Rassweiler will introduce John E. Trance,chairman of the Department of Chemistry, Washington Square College, who will welcome the group on behalf of the university. The technical program will consist of several addresses, following each of which time will be available for discussion. The speakers will describe the kinds of information that may be obtained by instrumental methods and the types of problems for which such methods are particularly suitable. Morning Session
Role of Instrumental Methods in Modern Analysis.
HALLETT, General Aniline and Film Corp., Easton, Pa.
L. T.
Mass Spectroscopy and Neutron Spectroscopy in Modern Columbia University, Kew York, N.Y. Analysis. T. IVANTAYLOR, Application of Infrared Spectroscopy to Organic Chemical Problems. ROBERTC. GORE,American Cyanamid Co., Stamford, Conn.
Microchemistry and the Petroleum Industry The Division of Petroleum Chemistry and the Division of Analytical and Micro Chemistry will jointly sponsor a Symposium on Microchemistry and the Petroleum Industry at the spring 1949 meeting of the AMERICAN CmnircAL SOCIETY in San Francisco. The joint session will be under the chairmanship of Harry Levin, The Texas Company, Beacon, X. Y. The scope of the symposium is being kept broad, and will include papers dealing with petroleum and its products, other hydrocarbons or mixtures of hydrocarbons, chemicals useful as additives for modifying the properties of petroleum products, chemicals manufactured from petroleum products-oxygenated compounds such as alcohols, glycols, ketones, etc., and sulfur compounds such as thiophene produced from petroleum. Papers may describe microchemical methods of analysis, microphysicochemical techniques, and synthesis by microprocedures. Those wishing to submit papers should get in touch with the chairman as promptly as possible,
Afternoon Session
X-Ray Diffraction as an Analytical Tool. I. FASKUCHEN, Brooklyn Polytechnic Institute, Brooklyn, K.Y. Analytical Applications of Electron Diffraction and Electron Microscoov. K. H. STORKS.Bell Teleohone Laboratories. Murray Hill, N. J. Particle Size Determination by Light Scattering. P. P. DEBYE,Bell Telephone Laboratories, Murray Hill, K. J.
Symposium on Instrumental Methods of Chemical Analysis. \\.ashington Square College, New York University, -New ’Iloik, N. Y., November 20, 1918. Fourth Annual Analytical Symposium. Hotel TTilliani Penn, Pittsburgh, P a . , January 20 and 21, 1949. Second Symposium on Analytical Chemistry. Louisiana State University, Baton Rouge, La., March 2 to 5 , 1949. Second Annual Summer Symposium on Analytical Chemistry. Tl-esleyan University, Middletown, Conn., June 1949.
