Asphalt compositions and the preparation thereof

Abstract

Asphalt compositions and methods of forming such are described herein. The asphalt compositions and methods of forming such are generally adapted to enable open air processing while producing asphalt compositions that exhibit properties capable of meeting SUPERPAVE™ specifications.

1 - 18 . (canceled) 
     
     
         19 . An asphalt composition made by a plurality of steps comprising:
 heating a base asphalt to a temperature of from 300° F. to 400° F.;   adding zinc oxide before any acid addition, and blending the asphalt;   adding from 0.01 wt. % to 2 wt. % of a mineral acid, and further blending the asphalt; and   wherein at least a portion of one or more of the blendings after zinc oxide addition occurs in the presence of an oxygen containing gas.   
     
     
         20 . The asphalt composition of  claim 19 , wherein the asphalt is blended in the presence of air for from 5 minutes to 2 hours. 
     
     
         21 . The asphalt composition of  claim 19  further comprised of from 0.001 wt. % to 5 wt. % of additives selected from the group consisting of sulfonating agents, cross-linking agents, emissions reducing additives, and combinations thereof, and wherein said additives are at least comprised of sulfur and mercaptobenzothizole (MBT). 
     
     
         22 . The asphalt composition of  claim 19 , wherein additional base asphalt is added to form a more dilute asphalt. 
     
     
         23 . The asphalt composition of  claim 19 , wherein aggregate is added to the asphalt to form a paving composition. 
     
     
         24 . An asphalt composition made by a plurality of steps comprising:
 heating a base asphalt to a temperature of from 300° F. to 400° F.;   introducing a polymer to form a polymer modified asphalt, and blending the polymer with the asphalt, wherein said asphalt has from 5 wt. % to 15 wt. % of the polymer;   adding zinc oxide before or after the polymer and before any acid addition, and further blending the asphalt;   adding from 0.01 wt. % to 2 wt. % of a mineral acid, and blending the asphalt; and   wherein at least a portion of one or more of the blendings after zinc oxide addition occurs in the presence of an oxygen containing gas, and wherein said polymer modified asphalt is comprised of at least 85 wt. % to 95 wt. % of asphalt.   
     
     
         25 . The asphalt composition of  claim 24 , wherein the polymer modified asphalt is blended in the presence of air for from 5 minutes to 2 hours. 
     
     
         26 . The asphalt composition of  claim 24  further comprised of from 0.001 wt. % to 5 wt. % of additives selected from the group consisting of sulfonating agents, cross-linking agents, emissions reducing additives, and combinations thereof, and wherein said additives are at least comprised of sulfur and mercaptobenzothizole (MBT). 
     
     
         27 . The asphalt composition of  claim 24 , wherein additional base asphalt is added to form a more dilute asphalt. 
     
     
         28 . The asphalt composition of  claim 24 , wherein aggregate is added to the asphalt to form a paving composition. 
     
     
         29 . A paving composition comprising an asphalt composition and aggregate, wherein the asphalt composition is made from the steps comprising:
 heating a base asphalt to a temperature of from 300° F. to 400° F.;   adding zinc oxide before any acid addition, and blending the asphalt;   adding from 0.01 wt. % to 2 wt. % of a mineral acid, and further blending the asphalt; and wherein at least a portion of one or more of the blendings after zinc oxide addition occurs in the presence of an oxygen containing gas.   
     
     
         30 . The paving composition of  claim 29  wherein the asphalt composition is made with the further step of introducing a polymer after heating the base asphalt to form a polymer modified asphalt, and blending the polymer with the asphalt, wherein said asphalt has from 0.01 wt. % to 15 wt. % of the polymer, and wherein the zinc oxide may be added before or after the polymer addition. 
     
     
         31 . The paving composition of  claim 29 , wherein the asphalt is blended in the presence of air for from 5 minutes to 2 hours. 
     
     
         26 . The paving composition of  claim 29 , wherein the asphalt composition is further comprised of from 0.001 wt. % to 5 wt. % of additives selected from the group consisting of sulfonating agents, cross-linking agents, emissions reducing additives, and combinations thereof, and wherein said additives are at least comprised of sulfur and mercaptobenzothizole (MBT). 
     
     
         27 . The paving composition of  claim 29 , wherein additional base asphalt is added to the asphalt composition form a more dilute asphalt. 
     
     
         28 . A method of forming a paving composition comprising:
 forming an asphalt composition comprising the steps of:
 heating a base asphalt to a temperature of from 300° F. to 400° F.; 
 adding zinc oxide and blending the asphalt and zinc oxide together, wherein the zinc oxide is added before or after a polymer and before any mineral acid, wherein zinc oxide is used as an additive for reducing hydrogen sulfide emissions, and wherein at least a portion of one or more of the blendings after zinc oxide addition occurs in the presence of an oxygen containing gas; 
 blending a mineral acid with an asphalt to form an acid modified asphalt; 
 blending the acid modified asphalt with a polymer selected from the group consisting of block copolymers, elastomeric polymers, or a combination thereof; 
   and wherein the asphalt composition is comprised of from 0.1 wt. % to 15 wt. % of the polymer, from 0.01 wt. % to less than 5 wt. % of the acid;   diluting the asphalt composition with additional base asphalt to form a diluted asphalt having a polymer composition of from 0.1 wt. % to 5 wt. %; and   combining the diluted asphalt with aggregate to form the paving composition.