A Fischer-Tropsch catalyst activation system including separation apparatus configured for separating a product gas comprising primarily hydrogen from a gas stream comprising hydrogen, an activation reactor fluidly connected with the separation apparatus via an activation gas inlet line whereby the product gas may be introduced into the activation reactor, and a circulation loop fluidly connecting a gas outlet of the activation reactor with the activation gas inlet line or with another gas inlet of the activation reactor and fluidly connecting the activation reactor with one or more apparatus configured for removal of H2O. A method of activating a Fischer-Tropsch catalyst is also provided.