Upgrading of cyclic naphthas
AssigneeUop LLC
InventorsLeonid B. Galperin, Jeffery C. Bricker, Jennifer S. Holmgren
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Abstract
A process combination is disclosed to selectively upgrade naphtha to obtain an isoparaffin-rich product for blending into gasoline. A naphtha feedstock is subjected to ring cleavage to convert naphthenes to paraffins using a nonacidic catalyst followed by isomerization of paraffins to obtain an increased proportion of isoparaffins. Ring cleavage also may be effected on the product of isomerization and separation by fractionation or adsorption.
Claims17
A process combination for selectively upgrading a naphtha feedstock comprising paraffins and naphthenes to obtain a product having an increased isoparaffin content comprising the steps of:
- (a) contacting the naphtha feedstock and a paraffinic intermediate in an isomerization zone maintained at isomerization conditions comprising a temperature of from 40.degree. to 250.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.2 to 15 hr.sup.-1 with a solid acid isomerization catalyst comprising at least one platinum-group metal component and recovering an isoparaffin-rich product;
- (b) separating the isoparaffin-rich product to obtain an isoparaffin concentrate and a cyclics concentrate;
- and,
- (c) converting the cyclics concentrate in a ring-cleavage zone with a nonacidic ring-cleavage catalyst, consisting essentially of at least one platinum-group metal component and a support selected from the group consisting of a nonacidic inorganic oxide, a metal-oxide solid solution and a nonacidic large-pore molecular sieve, at cleavage conditions comprising a temperature of from 100.degree. to 550.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.1 to 30 hr.sup.-1 to produce the paraffinic intermediate.
A process combination for selectively upgrading a naphtha feedstock comprising paraffins and naphthenes to obtain a product having an increased isoparaffin content comprising the steps of:
- (a) contacting the naphtha feedstock and a paraffinic intermediate in an isomerization zone maintained at isomerization conditions comprising a temperature of from 40.degree. to 250.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.2 to 15 hr.sup.-1 with a solid acid isomerization catalyst comprising at least one platinum-group metal component and recovering an isoparaffin-rich product;
- (b) separating the isoparaffin-rich product by molecular-sieve adsorption to obtain an isoparaffin concentrate and a cyclics concentrate;
- and,
- (c) converting the cyclics concentrate in a ring-cleavage zone with a nonacidic ring-cleavage catalyst, consisting essentially of at least one platinum-group metal component and a support selected from the group consisting of a nonacidic inorganic oxide, a metal-oxide solid solution and a nonacid large-pore molecular sieve, at cleavage conditions comprising a temperature of from 100.degree. to 550.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.1 to 30 hr.sup.-1 to produce the paraffinic intermediate.
A process combination for selectively upgrading a naphtha feedstock comprising paraffins and naphthenes to obtain a product having an increased isoparaffin content comprising the steps of:
- (a) contacting the naphtha feedstock and a paraffinic intermediate in an isomerization zone maintained at isomerization conditions comprising a temperature of from 40.degree. to 250.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.2 to 15 hr.sup.-1 with a solid acid isomerization catalyst comprising at least one platinum-group metal component and recovering an isoparaffin-rich product;
- (b) separating the isoparaffin-rich product to obtain an isoparaffin concentrate and a cyclics concentrate;
- and,
- (c) converting alkylcycloparaffins and cyclohexane in the cyclics concentrate in a ring-cleavage zone with a nonacidic ring-cleavage catalyst, comprising at least one platinum-group metal component and a support selected from the group consisting of a nonacidic inorganic oxide, a metal-oxide solid solution and a nonacidic large-pore molecular sieve, at cleavage conditions comprising a temperature of from 100.degree. to 550.degree. C., pressure of from 100 kPa to 10 MPa and liquid hourly space velocity of from 0.1 to 30 hr.sup.31 1 to produce the paraffinic intermediate.
Dependencies are inferred from the claim text.