C 14 dating benzene synthesis dating relationships 1950

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When three molecules of acetylene are thus attached, angular rotation is possible and a ring structure of benzene is thereby formed. the ring formation sometimes does not take place until after more than three acetylene molecules become so attached to a catalyst site, resulting in ethyl benzene being synthesized, thereby decreasing the benzene yield. In preparing benzene according to the practice of this invention the acetylene is passed through the catalyst mass. The process of claim 3 wherein the oxide conferring Lewis acid properties is W0 References Cited UNITED STATES PATENTS 2,846,490 12/1953 Witt 260673 2,990,434 6/1961 Smith 260673 PAUL M.

As indicated, the catalyst thus contacted contains an alumina base material making available a large surface area.

This discovery of carbon 14 in nature led to its development as an archaeological and geological calendar. PROCEDURE In order to prepare the benzene using the foregoing catalysts, the catalysts were first dehydrated. Results obtained by the use of these promoters in accordance with the procedures set forth were as follows: Based on the results obtained as shown in Table II, cobalt molybdate catalysts were selected for use in studying other variables in this benzene synthesis process. Analysis of a number of benzene samples showed the benzene purity to vary from 98-100% with acetone being the primary contamination and trace amounts of water and ethyl benzene also present.

A process is preferred whereby benzene can be synthesized from acetylene gas at near ambient temperature which will yield only pure benzene and no carbon isotope fractionation. This invention is a result of the study of this reaction. BENZENE SYNTHESIS WITII DEIIYDRATED CATALYTIC MATERIALS Conditions: Catalyst: As given. Table I also shows that catalysts are improved by cobait modification. The ratios of the peaks corresponding to the mass 28 and mass 27 molecules of acetylene for five separate analyses gave an average value of 0.0220.Such metal oxides are V205, Nb205, T3205, Cr O M003, W03 and M0205. Such variations and modifications are deemed to be Within the scope of this invention. A process for synthesizing substantially pure benzene by cyclic trimerization of acetylene which comprises trimerizing the acetylene in the gaseous phase at a temperature of 20 to 150 C.Normally there is no advantage to employing more than 30 weight percent metal oxide based on the catalyst. by bringing it into contact at said temperature with an oxide of one of the metals of Group VB and Group VIB of the Pen'odic Table having a valence V of 4 V 7, the oxide being supported on an activated alumina carrier, the metal being in said valence state in the oxide to confer Lewis acid properties on the combination, said carrier containing 3 to 30 weight percent of said oxide based on the total. The process of claim 1 wherein the cyclic trimerization temperature is 25 C. We recommend downloading the newest version of Flash here, but we support all versions 10 and above. P, isotopes used extensively as tracers in biomedical and biological research, was the trigger that prompted the commercial development of LS counters, first by Lyle Packard, the founder of the Packard Instrument Company, USA and then by many others in the USA and Europe.

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