Vulcanized rubber conversion

摘要

Vulcanized rubber, for example from used tires, can be devulcanized to provide a reaction product that has similar rheological properties to the original un-vulcanized rubber. The vulcanized rubber is processed at a temperature that is less than a critical temperature of a solvent, such as water or water and alcohol. The process is carried out at a pressure that is higher than the vapor pressure of the solvent.

主权项

1. A method of converting vulcanized rubber comprising:
heating in a reactor the vulcanized rubber and a solvent to a reaction temperature below 285° C.; providing a reaction pressure in the reactor that is higher than a saturated vapour pressure of the solvent at the reaction temperature, the reaction pressure provided in part by an inert gas over pressure of at least 300 psi; maintaining the reaction temperature and the reaction pressure for a reaction time sufficient to break at least a portion of crosslinks of the vulcanized rubber, wherein bulk devulcanization of the vulcanized rubber occurs when the reaction temperature and reaction pressure are maintained for the reaction time; and yielding an at least partially bulk devulcanized product.