The work introduced an innovative pathway for converting biomass-derived carbonyls into long-chain ethers, examining their low-temperature oxidation in a modified Cooperative Fuel Research (CFR) engine. The conversion of 2-butanone achieved 100 % and the selectivity of sec-butyl isopropyl ether reached the maximum of 83.13 % under optimal reaction conditions. Conversion of biomass-derived carbonyls increased from 31.77 % at 1 h to 36.28 % at 12 h, with the mass yield of long-chain ethers rising from 53.94 % to 62.86 %. At the same compression ratio, the maximum in-cylinder pressure and temperature increased as the long-chain ethers blending ratio increased. At the critical compression ratio, the net heat release rates (NHR) for blended fuels with 10 vol%, 20 vol% and 30 vol% long-chain ethers at the low-temperature heat release peak were 9.6 J/deg, 10.1 J/deg, and 10.0 J/deg better than that of n-heptane (6.3 J/deg), respectively. CO emissions from blended fuels before compression ignition were higher than n-heptane, while the value for the blended fuel with 30 vol.% long-chain ethers was reduced by 44.97 % compared to n-heptane after autoignition.