Vents and micro-structures of rubber molds may become clogged with rubber that is difficult to remove. These vents and micro-structures can be cleaned of rubber, even if heat aged, by subjecting the mold to high temperatures in the presence of a solvent to devulcanize any rubber present. If the rubber used with the mold being cleaned includes carbon black, a solvent may be used to dissolve the devulcanized polymer, leaving the carbon black which can be removed by water jets or other cleaning means.

Vents and micro-structures of rubber molds may become clogged with rubber that is difficult to remove. These vents and micro-structures can be cleaned of rubber, even if heat aged, by subjecting the mold to high temperatures in the presence of a solvent to devulcanize any rubber present. If the rubber used with the mold being cleaned includes carbon black, a solvent may be used to dissolve the devulcanized polymer, leaving the carbon black which can be removed by water jets or other cleaning means.

Methods of depolymerizing polyolefin-based material into useful petrochemical products using styrene oligomers or polymers, and heat are described. The styrene oligomers or polymers improve the depolymerization reaction by decreasing the halftime for the depolymerization, which results in a higher depolymerization rate and a shorter residence time in the depolymerization unit, allowing for a predictable depolymerization reaction, and decreasing the branching or aromatic formations in the product.

Methods of depolymerizing polyolefin-based material into useful petrochemical products using styrene oligomers or polymers, and heat are described. The styrene oligomers or polymers improve the depolymerization reaction by decreasing the halftime for the depolymerization, which results in a higher depolymerization rate and a shorter residence time in the depolymerization unit, allowing for a predictable depolymerization reaction, and decreasing the branching or aromatic formations in the product.

A method is provided for deconstructing macromolecules (MM) into lower molecular weight (MW) fragments in high yield by promoting first desirable reactions (Reactions1) that result in chemolytic scission of bonds in the backbone, chain, matrix, or network that defines the MM and obtain a first product mixture (Product1). The method includes conveying the prepared feedstock in a flowpath toward a reactor while adding a first agent of a first type (A1T1) suitable for promoting Reactions1, and a second agent (A2) suitable for promoting Reactions1 to obtain a first reaction mixture which is heated under controlled pressure.

Methods for depolymerization of a plastic polymer. An embodiment includes supplying a plastic polymer and aromatic bottoms from an aromatic recovery complex, the aromatic bottoms comprising C9+ aromatic compounds; dissolving the plastic polymer in the aromatic bottoms to obtain a dissolved plastic polymer solution comprising dissolved plastic polymer and C9+ aromatic compounds; and catalytically cracking the dissolved plastic polymer solution in the presence of a catalyst such that the dissolved plastic polymer and the C9+ aromatic compounds are cracked to obtain light products.

A method for reclaiming rubber comprises the steps of: (i) providing a starting material comprising a vulcanized rubber polymer; (ii) subjecting the starting material to mechanical stress and at a temperature of at least 200° C. to achieve at least a partial destruction of the cross-links and the backbone structure of the rubber polymer into fragments; and (iii) reconstituting at least part of the fragments in the presence of a branching/grafting agent to obtain a renewed rubber composition.

A method for reclaiming rubber comprises the steps of: (i) providing a starting material comprising a vulcanized rubber polymer; (ii) subjecting the starting material to mechanical stress and at a temperature of at least 200° C. to achieve at least a partial destruction of the cross-links and the backbone structure of the rubber polymer into fragments; and (iii) reconstituting at least part of the fragments in the presence of a branching/grafting agent to obtain a renewed rubber composition.

Methods for depolymerization of a plastic polymer. An embodiment includes supplying a plastic polymer and aromatic bottoms from an aromatic recovery complex, the aromatic bottoms comprising C9+ aromatic compounds; dissolving the plastic polymer in the aromatic bottoms to obtain a dissolved plastic polymer solution comprising dissolved plastic polymer and C9+ aromatic compounds; and catalytically cracking the dissolved plastic polymer solution in the presence of a catalyst such that the dissolved plastic polymer and the C9+ aromatic compounds are cracked to obtain light products.

Roadway resurfacing often requires removal of the existing asphalt from the roadway for reuse. One method of resurfacing a roadway is hot-in-place recycling. Hot-in-place recycling employs substantial heat to remove the oxidized or aged asphalt. This heat further oxidizes the asphalt, creating a material that lacks many desirable properties (e.g., flowability) and flexibility. The disclosure provides compositions and methods that enhance oxidized asphalt, making it more viable for use in resurfacing roadways. Accordingly, compositions comprising recycled asphalt pavement and a rejuvenating agent are disclosed. The compositions combine a rejuvenator and fresh asphalt flux to make a modified asphalt rejuvenator. The modified rejuvenator is then mixed with recycled asphalt pavement to form a rejuvenated asphalt composition.