Catalyst
The catalyst is a term
that has been widely known by researchers in the chemical process. The catalyst
is generally defined as substances that speed up or slow down the reaction.
These substances will be released again after the reaction is complete. The participation
of the catalyst in a chemical reaction that the catalyst is recovered at the
end of the reaction, but often changing its physical form. It could be argued
that the catalyst reacts participate but at the end of the reaction will be
formed again. The catalyst does not affect the position of equilibrium, but
only speed up reactions by lowering activation energy.
Based on the phase in the
reaction, the catalyst is classified into two namely:
1) Homogeneous Catalysts
If the catalyst phase by
phase as the reactants.
2) Heterogeneous
Catalysts
If the catalyst phase
different from phase reactants.
Generally, catalysts are
widely used in industry are heterogeneous catalysts. Heterogeneous catalyst is
generally in the form of metal oxide catalysts. Heterogeneous catalysts
typically are formed as solids are superimposed on the surface of the solid /
rest upon (impregnation) of the reactants. Katalisisnya mechanism takes place
in five stages that occur in sequence, namely the diffusion of reactants to the
catalyst surface, adsorption of reactants on the surface of the catalyst, the
product desorption from the catalyst surface and diffusion of products leaving
the catalyst surface (Wahyuni and Priatmoko, 2000).
