Aviation or motor fuels

Claim 1

A PROCESS FOR THE PRODUCTION OF A BLENDED HIGH GRADE AVIATION OR MOTOR FUEL HAVING AN ENGINE PERFORMANCE NUMBER AT LEAST SUBSTANTIALLY EQUAL TO THAT OF ISO-OCTANE BLENDED WITH 1.25 C.C. T. E. L. FLUID PER U. S. GALLON AS A MINIMUM STANDARD OF PERFORMANCE WHICH COMPRISES BLENDING AN ISOPENTANE FRACTION CONSISTING OF SUBSTANTIALLY PURE ISOPENTANE, AN "ISOHEXANE" FRACTION HAVING A BOILING RANGE OF 45-64* C., AND "ISOHEPTANE" FRACTION HAVING A BOILING RANGE OF FROM 70* C. TO ABOUT 92* C. TOGETHER WITH A PROPORTION OF TETRA ETHYL LEAD FLUID NOT EXCEEDING 6 CCS. PER IMPERIAL GALLON, SAID FRACTIONS BEING PRESENT EACH IN SIGNIFICANT AMOUNT TO PRODUCE A FINISHED BLEND OF THE STATED ENGINE PERFORMANCE NUMBER AND BEING DERIVED FROM THE DISTILLATION OF A STRAIGHT RUN PETROLEUM DISTILLATE OBTAINED FROM PARAFFINIC CRUDE AND BOILING IN THE AVIATION OR MOTOR SPIRIT RANGE UNDER CONDITIONS OF PRECISION IN FRACTIONATION INCLUDING THE USE OF NOT SUBSTANTIALLY LESS THAN 50 THEORETICAL PLATES AND A REFLUX RATIO OF NOT SUBSTANTIALLY LESS THAN 10:1, SAID ISOPENTANE FRACTION BEING ADDED IN SUCH PROPORTION NOT EXCEEDING 20% BY VOLUME OF THE FINISHED BLEND AS IS NECESSARY TO ENSURE THE REQUIRED VOLATILITY OF THE BLEND, SAID "ISOHEXANE" FRACTION BEING ADDED IN A PROPORTION NOT EXCEEDING 25% BY VOLUME OF THE FINISHED BLEND UP TO THE LIMIT OF VAPOUR TO LIQUID RATIO UNDER WHICH VAPOUR LOCK IS AVOIDED AND SAID "ISOHEPTANE" FRACTION BEING ADDED IN SUCH PROPORTION AS TO CONSTITUTE SUBSTANTIALLY THE REMAINDER OF THE BLAND.