Process for the production of carbon black

Abstract

A process for producing surface modified carbon black is disclosed. The process comprises the step of treating carbon black with a sulfur compound in an amount in the range of 0.005%-1% of the carbon black to effect in situ formation of surface groups to produce the surface modified carbon black which when combined with a polymer composition alters the carbon black-polymer interaction to decrease the hysteresis of the polymer composition. The curing time required for polymer composition comprising the surface modified carbon black is also decreased. The preferred sulfur compounds are sulfite or sulfate salts.

1 . A process for producing a surface modified carbon black comprising the step of treating carbon black with a sulfur-containing compound to obtain the surface modified carbon black which when combined with a polymer composition alters the carbon black-polymer interaction to decrease the hysteresis of the polymer composition by at least 1%. 
     
     
         2 . The process as claimed in  claim 1 , wherein the sulfur-containing compound is selected from the group consisting of sodium sulfate, sodium sulfide, sodium sulfite, sodium polysulfide, sodium thiosulfate, phenylene disulfide, alkali metal sulfate, alkali metal sulfite, alkali metal sulfide, alkaline earth metal sulfate, alkaline earth metal sulfite, alkaline earth metal sulfide, and mixtures thereof. 
     
     
         3 . The process as claimed in  claim 1 , wherein the sulfur-containing compound is used in an amount in the range of 0.005-1% of the carbon black. 
     
     
         4 . The process as claimed in  claim 1 , wherein the decrease in the hysteresis of the polymer composition is in the range of 1% to 20%. 
     
     
         5 . The process as claimed in  claim 1 , wherein the sulfur-containing compound is added during the manufacturing of the carbon black. 
     
     
         6 . The process as claimed in  claim 1 , wherein the sulfur-containing compound is added after the manufacturing of the carbon black. 
     
     
         7 . The process as claimed in  claim 1 , wherein the method step of treating carbon black with a sulphur-containing compound is carried out by a technique selected from the group consisting of pouring, spraying, injecting, dispersing and diffusing. 
     
     
         8 . The process as claimed in  claim 1 , wherein the sulfur-containing compound is in the form of dispersion. 
     
     
         9 . The process as claimed in  claim 1 , further comprises a step of mixing the sulfur-containing compound with process water to pelletize the carbon black.