With the purpose of obtaining of high-octane, ecologically clean components of engine fuels have been investigated through synthetic reactions of allyl-tret buthyl ethers (MTBE and ETBE) with the presence of modified silica-alumina catalysts.The optimal conditions of their obtaining (temperature 293-300 K, pressure 0.5-0.6 MPa, speed of volume of raw supply
1.0-1.2 h-1) have been detected.