Antonym of DISSIPATE

Dissipate : (with reference to a feeling or emotion) disappear or cause to disappear.
Sustain : strengthen or support physically or mentally.
Conserve : protect (something, especially something of environmental or cultural importance) from harm or destruction.
Preserve : maintain (something) in its original or existing state.
Maintain : cause or enable (a condition or situation) to continue.

Antonym of Dissipate is Conserve