The catalyst a substance increases the rate of a chemical reaction but which is left unchanged by the reaction. It works by providing a convenient extended surface for the reaction and by lowering the activation energy for the reaction. The reacting particles gather on the catalyst surface and collide more frequently with each other, thus increasing the reaction yield Introduction. The enzyme is an example of the catalyst used in the textile industry; such as, textile processing with bacteria or fungi culture. See also surface design in the Eco-Fashion Encyclopedia.