TITLE: Chemical Trapping of CO/H sub 2 Surface Species. Quarterly Report, September 1986.

AUTHOR: D. G. Blackmond;   I. Wender.

INST.  AUTHOR: Pittsburgh Univ., PA. Dept. of Chemical and Petroleum Engineering.

SPONSOR: Department of Energy, Washington, DC.

LANGUAGE: English

PUB.  TYPE: Technical Report

PUB.  COUNTRY: United States

SOURCE: Department of Energy [DE],  Sep 86,  6p.

NTIS ORDER NO.: DE87000637/INW

ABSTRACT:

The organometallic complex represents a system in which the species bound to the metal atoms is well-characterized; if we can follow the action of a trapping reagent on this known ''surface'' complex, perhaps we may obtain information about the mechanism of the reaction that will enable us to extend its use to catalytic surfaces where the adsorbed species is unknown. Experiments have been performed with ethylidyne tricobalt enneacarbonyl as a model organometallic complex. The chemical trapping reagents which have been employed include CH sub 3 I and (CH sub 3 ) sub 2 SO sub 4 . The complex and trapping reagent are mixed with a solvent such as dodecane. Reactions have been monitored between 80 deg C and 130 deg C.  The lower temperature limit represents the point at which the complex begins to react with the reagent, while the upper limit is near the temperature at which the complex begins to decompose. The results of the highest and lowest temperature experiments are shown. At low temperature, the predominant product indicates that two of the three CO-C bonds have been alkylated by the reagent, while the third was hydrogenated. The high temperature reaction showed significantly more neopentane, which is the expected product if the trapping reagent is 100% efficient. In addition, at high temperature there is a significant amount of C sub 2 and C sub 1 products which are listed as ''other.'' A blank run with the trapping reagent alone in the solvent showed that most of these products come from decomposition of the trapping reagent itself. Hence, the high temperature results indicate an even higher fraction of the expected product, neopentane, than is noted in the figure. (ERA citation 12:000273)

REPORT  NUMBER: DOE/PC/80526-T5

CONTRACT  NUMBER: FG22-85PC80526