World Wide Sales Offices of AMCEl and PAN AMCEL for Chemical Products of
CORPORATION
OF
AMERICA
Argentina, Buenos Aires Compafiia Sudamericana de Industrie y Comercio S.A. (Insud) Austria, Vienna XIX Eugen Farber Belgium, Gand Cocentra, S.P.R.L. Brazil, Sao Paulo..."Brasimet" Comercio e Industria S.A. Canada, Montreal, P.Q 'Canadian Chemical Co., Ltd. Canada, Toronto, Ont 'Canadian Chemical Co., Ltd. Canada, Vancouver, B.C 'Canadian Chemical Co., Ltd. Chile, Santiago M. Hochschild y Cia. Ltda. Colombia, Bogota 'Celanese Colombiana, S.A. Costa Rica, San Jose Servicios Técnicos Cuba, Havana Lainz y Compaliia Denmark, Copenhagen Johan Foge Jensen Ecuador, Quito Schiller y Cia. El Salvador, San Salvador Charles F. Rich & Co. England, London A. Revai & Co. (Chemicals) Ltd. France, Paris Pautrot & Bonnet Guatemala, Guatemala City Enrique Bauer Arzu Hawaii, Honolulu T. H. Davies & Co., Ltd. Holland, Amsterdam N. V. Consolco Hong Kong Optorg Co. (Malaya) Ltd. India, Bombay Banwari Lai & Co., Ltd. Indonesia, Djakarta-Kota Messers. N. V. Agung Israel, Tel-Aviv Manfred Gottesmann Italy, Milano Usvico (Société Industriale Commerciale) Malaya, Kuala Lumpur Getz Bros. & Co. Malaya, Singapore Getz Bros. & Co. Mexico, Mexico D.F 'Celanese Mexicana, S.A. Norway, Oslo Christen Hoeg Paraguay (offices in Montevideo, Uruguay) Armando Bachmann Sue. Peru, Lima George Checkley Philippines, Manila F. E. Zuellig Co., Inc. Rhodesia, Bulawayo John Beith (Rhodesia) (Pty.) Ltd. So. Africa, Durban (Portuguese East Africa, Nyasaland) John Beith (S.A.) Pty. Ltd. Spain, Barcelona Extrados Curtientes y Productos Qulmicos, S.A. Sweden, Stockholm A. B. Metal & Bergprodukter Switzerland, Basle..Chemische Fabrik Schweizerhall A.-G. Taiwan (Formosa), Taipei Dah Chung Trading Co. Thailand, Bangkok F. E. Zuellig & Co. Uruguay, Montevideo Armando Bachmann Sue. Venezuela, Caracas 'Celanese Venezolana, S.A. Vietnam (So.), Saigon & Loas. .Getz Bros. & Co. (Vietnam) West Germany, Hamburg Karl 0 . Helm •Affiliated Companies—Celanese Corporation of America
Amcel and Pan Amcel offer these chemical products of Celanese Corporation of America Acids Alcohols Aldehydes Anhydrides Esters Glycols
Ketones Polyols Vinyl Monomers Plasticizers Gasoline Additives Functional Fluids
AMCEL CO., INC. and PAN AMCEL CO., INC. 180 Madison Ave., New York 16 Affiliates
of Celanese Corporation
of America
For latest information on Celanese Chemicals see a d on Third Cover. Circle No. 60 Α οι Readers' Service Card, Page 101 A 60 A
IEC
INSTRUMENTATION
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with purged systems. Enclosure of the analysis unit in an explosion-resistant housing will be necessary to remove a major limitation. The basic work of simplifying and unitizing the construction has been done in this present instrument, and the final step to an explosionproof mass spectrometer is believed to be in progress. This mass spectrometer, with a resolution of 35 and a mass range from 2 to 80, will provide the basic data for accurate analyses of many chemical and petroleum process streams, but will be inadequate for other applications. The most serious limitation to continuous process use is the reduction of the data-to-stream analysis. The development of small, reliable, and economical equipment for direct readout and computation of the mass spectrum will be required before full use of the mass spectrometer can be made in process control. This will require advances in computer components and techniques and, until such equipment is available, process applications will be limited to those for which the mass spectrum will directly provide the analysis information' required. As a class, multicomponent hydrocarbon samples require computation, and this type of sample dominates in petroleum and petrochemical work. Simple computation is adequate and acceptable in many cases, particularly in pilot-plant and process-investigation work where skilled manpower is available. However, the full potential of process mass spectrometry will be greatly restricted until the readout is in sample-component percentages rather than in complex mass spectra. In a comparison of process mass spectrometry and process chromatography, the former has the advantage of speed of analysis. A single peak can be monitored with an instrument response of 1 second, enabling control of extremely fast processes if adequate sampling systems are devised. A multicomponent analysis may be needed for control. Several minutes are required for scanning a spectrum, and with a continuous sample system and rapidly changing process conditions, the sample at the end of a scan may be different from that at the start. This
INDUSTRIAL AND ENGINEERING CHEMIST!
A Workbook Feature
must be carefully considered. The speed of the mass spectrometer can be utilized for control only when a single peak provides the required information. High-speed readout-computer systems will be required for general applicability of the mass spectrometer to process control. The chromatograph analysis is representative of the stream composition at the instant the sample is taken, irrespective of the time lapse before the data is presented. The chromatograph spectrum is interpreted without computation, permitting direct analysis of many streams, which require computation with the mass spectrometer. However, a column must be developed for each application, often a compromise of resolution and analysis time must be made, and the time required to separate a large number of components tends to become very long. The gas chromatograph is not well adapted to continuous, automatic process control. The problems in applying mass spectrometry to continuous process control have been more with installation and operation than with analysis. Previously, the instruments have been small laboratory equipment and have required a small laboratory for their successful utilization. Maintenance and reliability have been a problem because of the exacting requirements placed on process analyzers. Instrument, installation, and maintenance costs have been high. The CEC 21-611 offers minor improvements in performance over preceding instruments, but, far more significantly, it presents a major advance in overcoming some of the application problems. This may result in a marked increase in continuous mass spectrometry in laboratory, pilot-plant, and continuous process control. The small mass spectrometer may prove to be a better competitor for the gas chromatograph than is generally believed possible.
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