Process for sulfuric acid extraction of tertiary olefins

Claim 1

A PROCESS FOR THE RECOVERY OF THE TERTIARY OLEFINIC CONTENT OF A MIXTURE CONTAINING AT LEAST ONE TERTIARY OLEFIN CONTAINING 4 TO 6 CARBON ATOMS AND AT LEAST ONE CLOSE BOILING OTHER HYDROCARBON, CONSISTING ESSENTIALLY OF CONTACTING THE MIXTURE WITH SULFURIC ACID HAVING AN H2SO4 CONCENTRATION BELOW 65 PERCENT UNDER CONDITIONS INCLUDING A TEMPERATURE NOT EXCEEDING 40*C. SUCH THAT SUBSTANTIALLY ONLY THE TERTIARY OLEFINIC CONTENT OF THE MIXTURE IS ABSORBED IN THE ACID, SEPARATING THE RESULTING ACID FROM THE UNABSORBED OTHER HYDROCARBON CONTENT, HEATING WITHOUT DILUTION THE ACID CONTAINING THE ABSORBED TERTIARY OLEFINIC CONTENT WITH INDIRECT HEAT AT THE RATE OF BETWEEN 1* TO 20*C. PER MINUTE TO A TEMPERATURE ABOVE 40*C. BUT NOT ABOVE ABOUT 70*C., AND RECOVERING THE RESULTING TERTIARY OLEFINIC CONTENT OF THE MIXTURE AND AN ACID HAVING SUBSTANTIALLY THE SAME H2SO4 CONCENTRATION AS THE ORIGINAL ACID.