The serious drawbacks from the use of oxygenates (MTBE, ETBE, TAME) from the refineries, in order to meet the current specifications of gasolines, could be overcome by using aqueous biphasic hydroformylation of alkenes from the light-light cracked naphtha (LLCN). This in situ and environmentally friendly catalytic process increases the concentration of molecular oxygen on the fuel by producing favorable oxygenated compounds (aldehydes or even alcohols), it improves the combustion properties and the storage stability of the fuel and it also increases the FON and the RON of the ultimate fuel. For the first time, hydroformylation of olefins present in a refinery (real) light light cracked naphtha was carried out in aqueous media. The influence of the reaction pressure (25-100 bar), temperature (30-130 degrees C) and reaction time (3-24 h), as well as the effect of the TPPTS/Rh (2-6) and olefins/Rh (125-1500) molar ratios were examined. The highest conversion of 95.4% of the olefins was observed at 70 degrees C, 100 bar, at a short reaction time (6 h). (C) 2012 Elsevier Ltd. All rights reserved.