TechnoCarbon Industries

THE MAJORITY OF ACTIVATED CARBON USED THROUGHOUT THE WORLD IS PRODUCED BY STEAM ACTIVATION. STEAM ACTIVATED CARBON IS PRODUCED BY TWO STAGE PROCESS. FIRSTLY THE MATERIAL IS CARBONIZED AND COKE IS PRODUCED. THE PORES OF PRODUCED COKE ARE SMALL; HENCE, THE NEXT STAGE IS A PROCESS OF ENLARGING THE PORE STRUCTURE SO THAT AN ACCESSIBLE INTERNAL SURFACE IS CREATED. THIS IS ACHIEVED BY REACTING SEMI PRODUCT WITH STEAM AT TEMPERATURE BETWEEN 900 and 1100 C. AT THIS TEMPERATURE RATE DETERMINATION FACTOR IS THE CHEMICAL REACTION BETWEEN STEAM AND CARBON. THIS REACTION TAKES PLACE AT THE INTERNAL SURFACE OF THE CARBON REMOVING CARBON FROM THE PORE WALLS AND THEREBY ENLARGING THEM. OPENING UP THE PORE STRUCTURE IS COSTLY AS THE YIELD DECREASES AND EXTRA HEAT IS REQUIRED. E.G. IN THE PURIFICATION OF WATER FOR THE ADSORPTION OF SMALL MOLECULES FROM SOLUTION. THIS CARBON IS CHEAPER COMPARE TO SUGAR DECOLORIZING CARBON WHERE LARGE MOLECULES ARE TO BE REMOVED. THUS, STEAM ACTIVATION PROCESS ALLOWS THE PORE SIZE TO BE ALTERED AND FINALLY CARBON CAN BE MADE TO SUIT DIFFERENT PURPOSES.

CHEMICAL ACTIVATED CARBON ARE PRODUCED BY MIXING CHEMICAL WITH A CARBONACEOUS MATERIAL USUALLY WOOD AND CARBONIZING THE MIXTURE. TEMPERATURE IS LOW, E.G. 400C-500C. CHEMICAL NORMALLY USED ARE PHOSPHORIC ACID AND ZINC CHLORIDE, WHICH OPEN UP THE CELLULOSE STRUCTURE OF WOOD. DURING CARBONIZATION THIS CHEMICAL ACTS AS A SUPPORT. PRESENCE OF CHEMICALS ALSO REDUCES TAR FORMATION AND LEADS TO A HIGHER YIELD. THE PHOSPHORIC ACID ACTIVATED CARBONS ARE ITSELF ACID WASHED CARBONS BUT DO NOT HAVE QUITE HIGH PURITY AS THE SPECIFICALLY ACID WASHED STEAM ACTIVATED CARBONS, AS THEY CONTAINS SMALL AMOUNT OF RESIDUAL PHOSPHATES. THE USE OF ZINC CHLORIDE AS AN ACTIVATING AGENT IS DECREASING BECAUSE OF THE ENVIRONMENT PROBLEMS AND FINAL PRODUCT CONTAINS RESIDUAL ZINC, WHICH IS UNDESIRABLE IN MANY APPLICATIONS.