TITLE: Promotion Effects on the Synthesis of Higher Alcohols. Fourth Quarterly Report, June 1983-August 1983.

AUTHOR: J. G. Goodwin;   S. C. Chuang.

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 83,  16p.

ABSTRACT:

Zn has been known as an essential element for the methanol synthesis.  Although the role of Zn in the synthesis of alcohols is still not clearly elucidated, the use of Zn-promoted catalysts may provide information permitting a better understanding of the role of Zn in CO hydrocondensation. It is therefore worthwhile to compare the effect of alkali promotion in to that by Zn. The effect of alkali promotion of Fischer-Tropsch (F-T) catalysts is well known. In general, upon promotion there is an increase in Co dissociation and hydrocarbon chain growth and a decrease in CH sub 4 selectivity. In the case of supported metals, such promotion has been found to be directly related to the alkali species-metal interaction and does not require support-metal interactions.  Surface science investigations of alkali metal atoms on transition metal surfaces have shown the presence of a transfer of charge from the alkali atoms to the metal surface atoms. Recently, an ESCA study of alkali-promoted Ru/SiO sub 2 demonstrated the apparent increase in valence electron density in Ru, even though promotion was by K exp + and Na exp + species. The use and effect of other promotes on F-T synthesis have not been studied extensively. Recent results have shown Ru supported on La sub 2 O sub 3 and ZnO to have interesting properties with respect to F-T synthesis. These properties were high olefin and low methane selectivities compared to Ru on a large number of other supports. Such catalysts, however, have a number of disadvantages. Ru/ZnO has a very low activity, while ZnO and La sub 2 O sub 3 have very low surface areas (10 to 30 m exp 2 /g) compared to SiO sub 2 or Al sub 2 O sub 3 . An investigation was carried out to determine the properties for F-T synthesis of La- and Zn- promoted Ru/SiO sub 2 and to compare these properties to those of Ru/La sub 2 O sub 3 and Ru/ZnO. (ERA citation 09:000307)

REPORT  NUMBER: DOE/PC/50810-T4

CONTRACT  NUMBER: FG22-82PC50810