Liquid washing effect observed in isothermal pilot unit

Claim 1

A METHOD OF HYDROGENATING A CHARGE MIXTURE OF HYDROCARBONS HAVING A 10 PERCENT POINT OF ABOUT 380* TO ABOUT 470*F., A 90 PERCENT POINT OF ABOUT 580* TO ABOUT 625*F., AND AN END BOILING POINTOF ABOUT 530* TO ABOUT 660*F., WHICH COMPRISES SUBJECTING THE AFORESAID HYDROCARBON MIXTURE SUBSTANTIALLY DEVOID OF ADDED DILUENT HYDROCARBONS TO REACTION TEMPERATURE OF AT LEAST ABOUT 750*F. AND A REACTION PRESSURE OF AT LEAST ABOUT 500 P.S.I.G. IN THE PRESENCE OF A PARTICLE-FORM CATALYTIC MATERIAL AND AT LEAST ABOUT 800 CUBIC FEET OF HYDROGEN PER BARREL OF HYDROCARBON MIXTURE WHILST ABOUT 0 TO ABOUT 35 PERCENT OF THE AFORESAID HYDROCARBON MIXTURE IS IN THE LIQUID PHASE UNTIL THE COLOR OF THE PRODUCT PRODUCED BECOMES DARKER THAN THAT OF THE PRODUCT AS ORIGINALLY PRODUCED, AND/OR CATALYST ACTIVITY DECREASES, REDUCTION THE REACTION TEMPERATURE BELOW 750*F. TO PROVIDE REACTION CONDITIONS UNDER WHICH THE VOLUME OF THE AFORESAID HYDROCARBON MIXTURE WHICH IS IN THE LIQUID PHASE IS INCREASED TO AT LEAST 20- 100 PERCENT OF SAID HYDROCARBON MIXTURE AND THE BALANCE IF ANY IS IN A VAPOR PHASE, SUBJECTING THE AFORESAID HYDROCARBON MIXTURE TO A TEMPERATURE BELOW 750*F. IN THE PRESENCE OF HYDROGEN WHILE ABOUT 20-100 PERCENT OF THE HYDROCARBON MIXTURE IS IN THE LIQUID PHASE UNTIL THE PRODUCT COLOR AND/OR CATALYST ACITVITY IS SUBSTANTIALLY IMPROVED BY CONTACT OF THE CATALYST WITH THE LIQUID PHASE MATERIAL THUS DERIVED SOLELY AND CREATED IN SITU FROM THE CHANGE MIXTURE, CHANGING SAID REACTION TEMPERATURE TO A REACTION TEMPERATURE OF AT LEAST ABOUT 750*F. TO PROVIDE REACTION CONDITIONS UNDER WHICH THE VOLUME OF THE AFORESAID HYDROCARBON MIXTURE WHICH IS IN THE LIQUID PHASE IS DECREASED SO THAT ONLY ABOUT 0-35 PERCENT OF SAID HYDROCARBON MIXTURE IS IN THE LIQUID PHASE, AND IN THE PRESENCE OF HYDROGEN BUT IN THE SUBSTANTIAL ABSENCE OF ADDED DILUENT HYDROCARBONS SUBJECTING THE AFORESAID HYDROCARBON MIXTURE HAVING ONLY ABOUT 0-35 PERCENT IN THE LIQUID PHASE TO A REACTION TEMPERATURE OF AT LEAST 750*F. AND A REACTION PRESSURE OF ABOUT 500 P.S.I.G., WHEREBY THE HYDROCARBON CONVERSION IS CARRIED OUT WITH THE SAME HYDROCARBON CHARGE MIXTURE THROUGHOUT THE ENTIRE OPERATION.