US 6,852,214 B1 · Gasoline sulfur reduction in fluid catalytic cracking

Abstract

The sulfur content of liquid cracking products, especially the cracked gasoline, of the catalytic cracking process is reduced by the use of a sulfur reduction additive comprising a porous molecular sieve which contains a metal in an oxidation state above zero within the interior of the pore structure of the sieve. The molecular sieve is normally a large pore size zeolite such as USY or zeolite beta or an intermediate pore size zeolite such as ZSM-5. The metal is normally a metal of Period 4 of the Periodic Table, preferably zinc or vanadium. The sulfur reduction catalyst may be used in the form of a separate particle additive or as a component of an integrated cracking/sulfur reduction catalyst.

Claims25

Dependent claims

A method of reducing the sulfur content of a liquid catalytically cracked petroleum fraction, which comprises catalytically cracking a petroleum feed fraction comprising a heavy hydrocarbon oil feed containing organosulfur compounds under catalytic cracking conditions of elevated temperature in the presence of an equilibrium cracking catalyst and a product sulfur reduction catalyst which comprises a porous molecular sieve having a metal component which is within the interior pore structure of the molecular sieve and which comprises vanadium in an oxidation state greater than zero in a matrix comprising alumina or silica-alumina with clay, to crack the heavy hydrocarbon feed to lighter liquid cracking products of reduced sulfur content.

In a fluid catalytic cracking process in which a heavy hydrocarbon oil feed comprising organosulfur compounds is catalytically cracked to lighter products by contact in a cyclic catalyst recirculation cracking process with a circulating fluidizable catalytic cracking catalyst inventory consisting of particles having a size ranging from about 20 to about 100 microns, comprising:

(i) catalytically cracking the heavy hydrocarbon oil feed in a catalytic cracking zone operating at catalytic cracking conditions of elevated temperature by contacting feed with a source of equilibrium cracking catalyst to crack the heavy hydrocarbon oil feed to lighter products and produce a cracking zone effluent comprising lighter cracked products and spent catalyst containing coke and strippable hydrocarbons;
(ii) discharging and separating the effluent mixture into a cracked product rich vapor phase and a solids rich phase comprising spent catalyst;
(iii) removing the vapor phase as a product and fractionating the vapor to form liquid cracking products including gasoline;
(iv) stripping the solids rich spent catalyst phase to remove occluded hydrocarbons from the catalyst;
(v) transporting stripped catalyst from the stripper to a catalyst regenerator;
(vi) regenerating stripped catalyst by contact with oxygen containing gas to produce regenerated catalyst;
and
(vii) recycling the equilibrium catalyst to the cracking zone to contact further quantities of heavy hydrocarbon feed, the improvement which comprises reducing the sulfur content of a gasoline portion of the liquid cracking products, by catalytically cracking the feed fraction at elevated temperature in the presence of a product sulfur reduction catalyst which comprises a porous molecular sieve having a metal component which is within the interior pore structure of the molecular sieve and which comprises vanadium in an oxidation state greater than zero in a matrix comprising alumina or silica-alumina with clay, to produce liquid cracking products of reduced sulfur content.

5 more elements

Dependencies are inferred from the claim text.

Gasoline sulfur reduction in fluid catalytic cracking

Life of this patent

Gasoline sulfur reduction in fluid catalytic cracking

Life of this patent

Abstract

Claims25