In the production of isobutylene-based elastomers the product obtained from the polymerization process is often in the form of a stream. Described herein are an apparatus and a process for removal of hydrocarbon liquids from the elastomer. The process comprises the steps of obtaining a stream comprising hydrocarbon liquids, either solvents or diluents, and an isobutylene-based elastomer; passing the stream through a kneader to volatize the hydrocarbon liquids from the elastomer.