A substance that increases the activity of a catalyst, when present in small quantity in the reaction mixture.

A reagent which speeds resin cure. See ACCELERATOR.

an accelerator of catalysis, but not a catalyst by itself

a substance which increases the efficiency of the catalyst

Any component added to a catalyst to increase activity or selectivity. Examples are tin added to platinum reforming catalysts to improve selectivity to coke formation and chloride added to isomerization catalysts to increase activity.

A substance that improves the activity of a catalyst, but which itself is not a catalyst.

A chemical, itself a weak catalyst. See accelerator.