Flexible process for transformation of ethanol into middle distillates implementing a homogeneous catalytic system and a heterogeneous catalytic system

摘要

The invention describes a process for the production of middle distillate hydrocarbon bases from an ethanol feedstock that is produced from a renewable source that is obtained from biomass, comprising a stage for purification of said feedstock, a stage for dehydration of said purified feedstock into an effluent that is for the most part ethylene and comprises water, at least one stage for separating water, a first stage for oligomerization of the effluent that is for the most part ethylene into at least one olefinic effluent that comprises at least 80% by weight of olefins that have four or more carbon atoms, in the presence of a homogeneous catalyst that comprises at least one bivalent nickel compound, whereby a second oligomerization stage produces middle distillate hydrocarbon bases in the presence of an amorphous or zeolitic catalyst that has at least pore openings that contain 10 or 12 oxygen atoms, producing middle distillate hydrocarbon bases, and a fractionation stage.

主权项

1. A process for the production of a kerosene hydrocarbon base from an ethanol feedstock that is produced from a renewable source that is obtained from biomass, said process comprising:
a) a stage for purification of said ethanol feedstock, b) a stage for dehydration of the purified ethanol feedstock obtained from purification stage a) into an effluent, wherein said effluent is for the most part ethylene and also comprises water, and wherein said dehydration is conducted in the presence of an amorphous acid catalyst or a zeolitic acid catalyst, c) at least one stage for separation of the water that is present in said effluent obtained from dehydration stage b), d) a first stage for oligomerization of at least a portion of the effluent obtained from separation stage c) to form at least one olefinic effluent that comprises at least 80% by weight of olefins that have four or more carbon atoms, relative to the total mass of the olefins that are contained in said least one olefinic effluent, and wherein oligomerization is performed in the presence of a homogeneous catalyst that comprises at least one bivalent nickel compound, said homogeneous catalyst being soluble in a liquid phase of ethylene and its oligomerization products, e) a second stage for oligomerization of at least a portion of the olefinic effluent obtained from first oligomerization stage d), to produce an effluent comprising middle distillate hydrocarbon bases, wherein oligomerization in the second oligomerization stage e) is performed in the presence of an amorphous catalyst, and wherein said second oligomerization stage e) is performed in at least one fixed-bed reactor operating at a temperature of between 50 and 400° C., at an absolute pressure of between 2 and 15 MPa, and at an hourly speed by weight of between 0.1 and 50 h−1, and f) a stage for fractionation of the effluent obtained from the second oligomerization stage e) to obtain said kerosene hydrocarbon base.