초록 ▼

A hydrocarbon feedstock is catalytically reformed in a sequence comprising a zeolitic-reforming zone containing a catalyst comprising a platinum-group metal and a nonacidic L-zeolite and an aromatics-isomerization zone containing a catalyst comprising a medium-pore molecular sieve, a platinum-group

A hydrocarbon feedstock is catalytically reformed in a sequence comprising a zeolitic-reforming zone containing a catalyst comprising a platinum-group metal and a nonacidic L-zeolite and an aromatics-isomerization zone containing a catalyst comprising a medium-pore molecular sieve, a platinum-group metal and a refractory inorganic oxide. Optionally, the zeolitic-reforming zone is preceded by a continuous-reforming zone associated with continuous catalyst regeneration, The process combination features high selectivity in producing a high-purity BTX product from naphtha.

대표청구항 ▼

[ We claim:] [1.] A process combination for the upgrading of a hydrocarbon feedstock to a concentrated BTX (benzene, toluene and xylenes) product comprising the steps within the same hydrogen circuit of:(a) contacting the hydrocarbon feedstock in the presence of free hydrogen in a zeolitic-reforming

[ We claim:] [1.] A process combination for the upgrading of a hydrocarbon feedstock to a concentrated BTX (benzene, toluene and xylenes) product comprising the steps within the same hydrogen circuit of:(a) contacting the hydrocarbon feedstock in the presence of free hydrogen in a zeolitic-reforming zone at zeolitic-reforming conditions comprising a pressure of from about 100 kPa to 6 MPa, a temperature of from 260.degree. to 560.degree. C., and a liquid hourly space velocity of from about 0.5 to 40 hr.sup.-1 with a zeolitic reforming catalyst comprising a nonacidic large-pore zeolite having a pore size of at least 6 .ANG., a refractory inorganic oxide and a platinum-group metal component to produce an aromatics-enriched effluent; and,(b) contacting the aromatics-enriched effluent without extraction of aromatics therefrom in an aromatics-isomerization zone at aromatics-isomerization conditions comprising a pressure of from about 100 kPa to 3 MPa, a temperature of from 300.degree. to 500.degree. C., and a liquid hourly space velocity of from about 0.2 to 100 hr.sup.-1 with an aromatics-isomerization catalyst comprising a medium-pore molecular sieve having a pore size of between about 5 and 6.5 .ANG., a refractory inorganic oxide and a platinum-group metal component to obtain the concentrated BTX product wherein a xylene concentrate from fractionation of the BTX product contains no more than about 5 mass-% ethylbenzene.