Selective naphtha reforming systems

A system for reforming a hydrocarbon feedstock, comprising:

• a) A first reforming unit that contains a first reforming catalyst comprising a solid support that comprises acidic sites,
• wherein the first reforming unit is operable to receive a hydrocarbon feedstock comprising
• paraffins and naphthenes, each of which comprises from four to twelve carbon atoms, wherein the hydrocarbon feedstock is characterized by a boiling point ranging from −12° C. to 230°C.,
• wherein the first reforming unit is operable to facilitate contact between the hydrocarbon feedstock and the first reforming catalyst to produce a first reformer effluent comprising predominantly aromatics,
• wherein the first reforming unit is further operable to maintain a temperature, a pressure and a hydrogen to hydrocarbon ratio that facilitates the catalytic aromatization of naphthenes in the feedstock by the first reforming catalyst, while simultaneously facilitating the catalytic dehydrogenation, catalytic cracking, or both, of less than 50% of paraffins in the hydrocarbon feedstock;
• b) A separation unit operable to separate the first reformer effluent into a first fraction that comprises an increased percentage (by weight) of aromatics relative to the first reformer effluent, and a second fraction that comprises an increased percentage (by weight) of paraffins relative to the first reformer effluent;
• c) A second reforming unit that contains a second reforming catalyst comprising a solid support that does not contain acidic sites,
• wherein the second reforming unit is operable to receive the second fraction and facilitate contact between the second fraction and the second reforming catalyst and further operable
• to maintain a temperature, a pressure and a hydrogen to hydrocarbon ratio that are suitable
• to facilitate catalytic dehydrogenation of at least 50 wt. % of paraffins present in the second
• fraction to produce a second reformer effluent comprising predominantly olefins containing four or five carbon atoms and unreacted paraffins, wherein the second reformer
• effluent is characterized by an increased research octane number relative to the second fraction;
• d) a distillation unit operable to separate the second reformer effluent into a light hydrocarbons fraction comprising hydrocarbons containing one to four carbon atoms, and a heavy hydrocarbons fraction comprising hydrocarbons containing five or more carbon atoms, and
• e) an oligomerization reactor containing an oligomerization catalyst, wherein the oligomerization reactor is operable to receive the light hydrocarbon fraction and facilitate contact between the light hydrocarbon fraction and the oligomerization catalyst at conditions of temperature and pressure suitable to produce an oligomerization product comprising larger hydrocarbons containing five or more carbon atoms that are characterized by a decreased vapor pressure.