TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The catalyst used in step (a) is a zeolite catalyst including zeolite having pores containing 10 or 12 oxygen atoms. The catalyst used in step (a) is an amorphous acid catalyst comprising at least a porous refractory oxide, preferably alumina, alumina activated by depositing mineral acid or alumina-silica.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The step of purification of the feed comprising butanol and pentanol is carried out prior to step (a). The step (b) is a decantation step in which an aqueous phase is separated from an organic phase. In step (g), 90-100% of the total mass of the intermediate product is treated. In step (h), at least 90% of the total mass of the middle distillate product is treated. The step (f) is carried out in 2 fractionating columns operative in series, where the column includes an internal wall. The process comprises a step of separation of the product obtained from hydrogenation to allow fractionation to a kerosene fraction, a diesel fuel fraction, a fraction having a boiling point of higher than 360 degrees C and/or light fractions. EXAMPLE - A feed including butanol and pentanol was subjected to dehydration isomerization at a temperature of 400 degrees C, a pressure of 0.85 MPa and at feed rate 5 per hour in the presence of a ZSM-23 catalyst to obtain an olefinic effluent containing butylenes and pentenes. The effluent was directed towards a decantation unit to carry out the separation of water at 50 degrees C and 0.75 MPa to obtain organic effluent. The organic liquid effluent was purified to withdraw the major part of remaining water and compounds capable of attacking the catalytic bed downstream. The sulfurated elements, nitrogenized and oxygenated elements and remaining water was removed using a molecular sieve 3A. The purified effluent was oligomerized in the presence of IP811 catalyst (amorphous silica-alumina catalyst) at a temperature of 60 degrees C, a pressure of 3 MPa and rate of 2 per hour. The resulting effluent was subjected to selective oligomerization with 75% of the total flow of the effluent of fractionation in the presence of IP811 catalyst at a temperature of 110 degrees C, a pressure of 6 MPa and rate of 2 per hour. The resulting oligomerization product was fractionated to separate a 328 g/hour of light product including 2-5C compounds, 296 g/hour of an intermediate product including 6-9C compounds and 690 g/hour of a middle distillate product including kerosene fraction (10C+ fraction). The intermediate product containing 8C compounds was oligomerized in the presence of IP811 catalyst at a temperature of 110 degrees C, a pressure of 6 MPa and a rate of 2 per hour. The middle distillate product was hydrogenated in the presence of a LD746 catalyst, where the major part of olefins was hydrogenated while minimizing the production of light hydrocarbon molecules. The hydrogenation step was carried out at a temperature of 160 degrees C and a pressure of 2.5 MPa and a ratio of hydrogen-hydrocarbon of 100 to produce a mixture of 9-16C alkanes.