摘要:
The present invention provides a method for preparing an asphalt and thermoplastic elastomer composition. The process comprises heating an asphalt cut in a stirred tank to a temperature sufficient to allow the stirring of the asphalt in the tank. A thermoplastic elastomer or rubber is added to the asphalt while continuing to stir the asphalt. The mixture is stirred at a speed and for a period of time sufficient to increase the distribution of the elastomer into the asphalt. The stirring speed is reduced and the temperature is increased to add crosslinking agents to the tank. Stirring is continued for a period of time sufficient to improve the distribution of the crosslinking agent dispersion in the asphalt. Crosslinking agents include compositions of mercaptobenzothiazole, zinc oxide and elemental sulfur; compositions of mercaptobenzothiazole, zinc oxide, and mixed polythiomorpholine; and compositions of zinc 2-mercaptobenzothiazole and dithiodimorpholine.
摘要:
The present invention provides a method for preparing an asphalt and thermoplastic elastomer composition. The process comprises heating an asphalt cut in a stirred tank to a temperature sufficient to allow the stirring of the asphalt in the tank. A thermoplastic elastomer or rubber is added to the asphalt while continuing to stir the asphalt. The mixture is stirred at a speed and for a period of time sufficient to increase the distribution of the elastomer into the asphalt. The stirring speed is reduced and the temperature is increased to add crosslinking agents to the tank. Stirring is continued for a period of time sufficient to improve the distribution of the crosslinking agent dispersion in the asphalt. Crosslinking agents include compositions of mercaptobenzothiazole, zinc oxide and elemental sulfur; compositions of mercaptobenzothiazole, zinc oxide, and mixed polythiomorpholine; and compositions of zinc 2-mercaptobenzothiazole and dithiodimorpholine.
摘要:
The present invention provides a method for preparing an asphalt and thermoplastic elastomer composition. The process comprises preparing a crosslinking elastomer concentrate that is added to a heated asphalt cut in a stirred tank and then aged to improve SHRP high temperature grading. The crosslinking elastomer concentrate is prepared by adding thermoplastic elastomer and crosslinking agents to a suitable carrier oil, preferably an aromatic oil such as Hydrolene H series. This concentrate is maintained at a temperature that promotes association between the crosslinking agents and the elastomer for a time sufficient for association to substantially complete. In one embodiment, the associating time is in excess of 2 hours up to 24 hours. The asphalt is heated to a temperature sufficient to allow the stirring of the asphalt in the tank. The crosslinking thermoplastic elastomer concentrate is added to the asphalt while continuing to stir the asphalt. The mixture is stirred at a speed and for a period of time sufficient to increase the distribution of the elastomer into the asphalt. Stirring is continued for a period of time sufficient to improve the distribution of the crosslinking thermoplastic elastomer in the asphalt. The composition is then aged as a liquid for 12 to 48 hours to increase the SHRP high temperature grade.
摘要:
Alkylation systems and methods are described herein and generally include contacting an alkyl aromatic hydrocarbon with a cerium promoted zeolite catalyst and then contacting the alkyl aromatic hydrocarbon with an alkylation catalyst to form a second aromatic hydrocarbon.
摘要:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase in a reaction zone containing a molecular sieve aromatic alkylation catalyst comprising cerium-promoted zeolite beta. A polyethylbenzene is supplied into the reaction zone and into contact with the cerium-promoted zeolite beta having a silica/alumina mole ratio within the range of 20-500. The reaction zone is operated at temperature and pressure conditions in which benzene is in the supercritical phase to cause ethylation of the benzene and the transalkylation of polyethylbenzene and benzene in the presence of the zeolite beta catalyst. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated byproducts of no more than 60 wt. % of the ethylbenzene. The alkylation reaction zone is operated under conditions providing a composite byproduct yield of propyl benzene and butyl benzene relative to ethylbenzene, which is no more than one half of the corresponding yield byproduct for zeolite beta promoted with lanthanum. The production of ethylbenzene in the critical phase alkylation reaction zone is attended by recycle of a polyalkylated aromatic component of the reaction product back to the reaction zone.
摘要:
A process for the regeneration of a deactivated zeolite beta catalyst such as rare earth promoted zeolite beta catalyst deactivated in the course of an aromatic alkylation reaction. A zeolite beta conversion catalyst deactivated with the deposition of coke is heated to a temperature in excess of 300° C. in an oxygen-free environment. An oxidative regeneration gas is supplied to the catalyst bed with oxidation of a portion of a relatively porous coke component to produce an exotherm moving through the catalyst bed. At least one of the temperature and oxygen content of the gas is progressively increased to oxidize a porous component of the coke. Regeneration gas is supplied having at least one of an increased oxygen content or increased temperature to oxidize a less porous refractory component of the coke. The regeneration process is completed by passing an inert gas through the catalyst bed at a reduced temperature.
摘要:
The present invention provides a dispersing agent that facilitates the delivery of a cross-linking agent to polymer modified asphalt. The present invention further includes a composition comprising a liquid hydrocarbon, the dispersant and cross-linking agent, and methods of preparing the composition and of preparing cross-linked polymer modified asphalt composition.
摘要:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase over a molecular sieve aromatic alkylation catalyst comprising cerium-promoted zeolite beta. An aromatic feedstock having a benzene content of at least 90 wt. % is supplied into a reaction zone and into contact with the cerium-promoted zeolite beta having a silica/alumina mole ratio within the range of 50-150 and a cerium-aluminum ratio of 0.5-1.5. Ethylene is supplied to the alkylation reaction zone in an amount to provide a benzene/ethylene mole ratio of 1-15. The reaction zone is operated at temperature and pressure conditions in which benzene is in the super critical phase to cause ethylation of the benzene in the presence of the cerium zeolite beta alkylation catalyst. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated by-products of no more than 60 wt. % of the ethylbenzene. The critical phase alkylation reaction may be followed by the transalkylation of a polyalkylated aromatic component.
摘要:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase in a reaction zone containing a molecular sieve aromatic alkylation catalyst comprising cerium-promoted zeolite beta. A polyethylbenzene is supplied into the reaction zone and into contact with the cerium-promoted zeolite beta having a silica/alumina mole ratio within the range of 20-500. The reaction zone is operated at temperature and pressure conditions in which benzene is in the supercritical phase to cause ethylation of the benzene and the transalkylation of polyethylbenzene and benzene in the presence of the zeolite beta catalyst. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated byproducts of no more than 60 wt. % of the ethylbenzene. The alkylation reaction zone is operated under conditions providing a composite byproduct yield of propyl benzene and butyl benzene relative to ethylbenzene, which is no more than one half of the corresponding yield byproduct for zeolite beta promoted with lanthanum. The production of ethylbenzene in the critical phase alkylation reaction zone is attended by recycle of a polyalkylated aromatic component of the reaction product back to the reaction zone.
摘要:
A process for the preparation of an asphalt and polymer composition in which a minor amount of polymer component is subjected to a crosslinking. An asphalt base material is heated in a mixing chamber at a temperature sufficient to melt the asphalt and allow stirring of the asphalt within the chamber. A thermoplastic elastomer is added to the chamber in an amount not greater than 12 wt. %. While the asphalt elastomer formulation is stirred, a crosslinking agent is added in an amount effective to crosslink the thermoplastic elastomer. The crosslinking agent formulation comprises at least two components. One component is a thiopolymer incorporating organic sulfur prepared by the reaction of 6-tertiary butyl cresol and sulfur dichloride which reacts to produce a reaction product comprising 4,4-thiobis(6-tertiary butyl-m-cresol) and the thiopolymer, followed by subsequent separation of the 4,4-thiobis(6-tertiary-butyl-m-cresol) from the thiopolymer product. The second crosslinking component comprises a source of sulfur to crosslink the thermoplastic elastomer. The second crosslinking component may be selected from the group consisting of elemental sulfur, polythiomorpholine, specifically dithiodimorpholine, zinc-2-mercaptothiazole and mixtures thereof