intellect：是指思考或领悟的能力，不受感情或意志的影响 intelligence：指处理问题或情况的能力；也指展开、运用智慧的能力

I would say that intellect deals with the amount of knowledge someone has and the ability to understand it. Intelligence is the ability to use knowledge, innovate and think. This is why an intelligent person doesn't have to be an intellectual.