Supported copper or especially nickel catalysts are very important for hydrogenation of various organic compounds in the practice. Activity, selectivity and stability can be greatly improved using co-catalysts: e.g. chromium compounds with Cu (Adkins catalyst for fatty alcohol production) or molybdenum compounds with Ni (for hydrodesulfurization [HDS], hydrodeoxygenation [HDO], hydrodenitrogenation [HDN], etc. catalysts in petroleum refining.Recently, we discovered novel highly efficient bimetallic supported catalysts which were exceedingly active and selective in the hydrodeoxygenation (HDO) of octanoic acid to octanol at moderate pressure and temperature in addition very effective in reduction of acetic acid to ethanol. The catalysts contained indium as co-catalyst and a metal of high hydrogenation activity, such as, copper or nickel, on various support. A significant synergism can be observed when indium with another metal of hydrogenation activity is applied. Appearance of Cu2In or Ni2In phases, intermetallic compounds on the surface of metal particles results in significant increase of desired hydrogenation activity, i.e., in stepwise hydrogenation of carboxylic acids stopped at alcohol formation and in inhibiting hydrogenations when hydrodecarbonylation of carboxylic acids (loss of one carbon atom) and hydrogenolysis of hydrocarbon products (loss of further carbon atoms) proceed. Moreover, in presence of mobile indium atoms or of indium containing nano clusters mono- or bimolecular alcohol dehydration capability of the support is selectively poisoned.In order to have more information about the role of indium, experiments are carried out using quite different hydrogenation metals, Cu and Ni. Hydrogenation experiments are carried out with long chain fatty acid like octanoic acid for production of octyl alcohol and short chain acetic acid (produced in large amounts from biomass) for production of ethyl alcohol, ethyl acetate or acetaldehyde. The main question is how the co-catalyst second metal of moderate hydrogenation activity as gallium, cadmium, tin, but first of all indium, modify the activity of the supported hydrogenation metal and the surface properties of the support.
|Title of host publication||Indium|
|Subtitle of host publication||Properties, Technological Applications and Health Issues|
|Publisher||Nova Science Publishers, Inc.|
|Number of pages||27|
|Publication status||Published - Jan 1 2013|
ASJC Scopus subject areas
- Chemical Engineering(all)