摘要:
A method of rejuvenating a deactivated molecular sieve catalyst, deactivated by use in an olefin oligomerization or aromatics alkylation process, which method comprises contacting the deactivated catalyst with a stream of rejuvenation gas comprising a hydrocarbon product fraction from the process at an elevated temperature and pressure for a time sufficient to effect an increase in catalytic activity of the deactivated catalyst.
摘要:
A process unit for the zeolite-catalyzed conversion of light refinery olefins from an FCC unit such as ethylene, propylene, and butylene to gasoline boiling range motor fuels comprises at least two sequential, serially connected reactors connected in parallel to a fractionation section with at one or two fractionators for separating the reactor effluents into product fraction with an optional recycle stream or streams. The configurations according to this scheme allow the adjustment of reactor temperature and/or pressure and/or space velocity to be based on the reactivities of the olefin compounds present in the LPG streams so that the gasoline produced in each reactor will be separated immediately, to reduce over-polymerization of the gasoline in the low severity reactor and to ensure that gasoline formed in the low severity reactor will not be sent to the higher severity reactor e.g. with a higher reactor temperature, where excessive polymerization to undesirable higher molecular with products may take place.
摘要:
A process for the removal of sulfur compounds and benzene of a catalytically cracked petroleum naphtha comprising benzene, organic sulfur compounds and olefins, by fractionating the cracked naphtha into a relatively low boiling range, olefinic, light catalytic naphtha (LCN) and an olefinic heavy catalytic naphtha (HCN) which boils above the range of the LCN the boiling ranges of the LCN and the HCN being defined by a cut point selected to maintain most of the benzene in the cracked naphtha in the LCN together with olefins in the boiling range of the LCN. The LCN is subjected to an optional non-hydrogenative desulfurization step followed by a fixed bed alkylation step in which the benzene in the LCN is alkylated with the olefins contained in this fraction. The HCN is treated by a similar an alkylation step using the olefins contained in this fraction to alkylate the sulfur compounds, forming alkylated products which boil above the gasoline boiling range. The LCN and HCN are then fractionated to remove light ends and higher boiling sulfur reaction products (disulfides, alkylated thiophenes) boiling above the gasoline boiling range.
摘要:
A process for the removal of sulfur compounds and benzene of a catalytically cracked petroleum naphtha comprising benzene, organic sulfur compounds and olefins, by fractionating the cracked naphtha into a relatively low boiling range, olefinic, light catalytic naphtha (LCN) and an olefinic heavy catalytic naphtha (HCN) which boils above the range of the LCN the boiling ranges of the LCN and the HCN being defined by a cut point selected to maintain most of the benzene in the cracked naphtha in the LCN together with olefins in the boiling range of the LCN. The LCN is subjected to an optional non-hydrogenative desulfurization step followed by a fixed bed alkylation step in which the benzene in the LCN is alkylated with the olefins contained in this fraction. The HCN is treated by a similar an alkylation step using the olefins contained in this fraction to alkylate the sulfur compounds, forming alkylated products which boil above the gasoline boiling range. The LCN and HCN are then fractionated to remove light ends and higher boiling sulfur reaction products (disulfides, alkylated thiophenes) boiling above the gasoline boiling range.
摘要:
A process for the production of high octane number gasoline from light refinery olefins, typically from the catalytic cracking unit, and benzene-containing aromatic streams such as reformate. A portion of the light olefins including ethylene and propylene is polymerized to form a gasoline boiling range product and another portion is used to alkylate the light aromatic stream. The alkylation step may be carried out in successive stages with an initial low temperature stage using a catalyst comprising an MWW zeolite followed by a higher temperature stage using a catalyst comprising an intermediate pore size zeolite such as ZSM-5. Using this staged approach, the alkylation may be carried out in the vapor phase. Alternatively, the alkylation may be carried out in the liquid phase using the heavier olefins (propylene, butene) dissolved into the aromatic stream by selective countercurrent extraction; a separate alkylation step using the ethylene not taken up in the extraction is carried out at a higher temperature.
摘要:
A process for the production of high octane number gasoline from light refinery olefins and benzene-containing aromatic streams such as reformate. The process achieves good utilization of both the ethylene and the propylene present in the mixed olefin feed from the unsaturated gas plant while reducing gasoline benzene levels. The light olefins including ethylene and propylene are reacted with the light aromatic stream containing benzene and other single ring aromatic compounds to form a gasoline boiling range product containing akylaromatics. The reaction is carried out with a two-catalyst system which comprises a member of the MWW family of zeolites and an intermediate pore size zeolite such as ZSM-5 using a fixed catalyst bed in both stages. Use of the two catalyst system enables the conversion of the ethylene and propylene components of the olefin feed to be converted to alkylaromatics under favorable conditions.
摘要:
Systems and methods for determining the flow distribution of a fluid through a component with a sensing cable including an optical fiber sensor array aligned with a heating element disposed in the component. An excitation source is configured to propagate at least one heat pulse through the heating element along at least a portion of the sensing cable to affect an exchange of thermal energy between the heating element and the fluid exposed to the sensing cable. An optical signal is adapted to receive a signal from each of a plurality of sensor locations and measure a temperature profile corresponding to the heat pulse at the sensor locations. A control unit is configured to determine a flow of the fluid by determining one or more properties of the fluid exposed to the sensing cable at each of the plurality of sensor locations based on the temperature profile corresponding thereto. The present invention can be effective in accurate and high spatial resolution of flow distributions through vessel components, such as a particulate bed (such as a reactor catalyst bed), a wash bed including packing material, an absorbent bed, a structured bed, a filter, or the like.
摘要:
A divided wall column can allow for fractionation of multiple streams while maintaining separate product qualities. Effluents from multiple stages of a reaction system can be processed in a single divided wall column. The divided wall column can produce multiple cuts from each separated area, as well as at least one output from a common area. At least one reaction stage can advantageously have a continuous liquid phase environment.
摘要:
A process for the alkylation of a benzene-containing refinery stream such as reformate with light refinery olefins which is capable of achieving high benzene conversion levels operates in a fixed bed of an MWW zeolite catalyst, preferably MCM-22, in single pass mode in the liquid phase at a relatively low to moderate temperatures with pressure maintained at a value adequate to ensure subcritical operation. High levels of benzene conversion with conversions of at least 90% and higher, e.g. 92% or 95% or even higher are achievable. A high octane product is produced, comprising mono-, di- and tri-alkylbenzenes with lesser levels of the tetra-substituted products. By operating with staged olefin injection, the end point of the alkylation product can be maintained at a low value while, at the same time, achieving high levels of benzene and olefin conversion.
摘要:
A structure and method are provided for adding a catalyst bed platform to an existing reactor without welding to the structural portion of the reactor walls. The structure is constructed from components that can be passed through an existing opening in a reactor. The structure allows a catalyst bed in an existing reactor to be divided into catalyst beds with a reduced length to diameter ratio.