Abstract: A novel fractionation column (1) internal structure consists of bundles of fractionation trays in which each upper tray rests upon the next lower tray. Only the lowermost tray of the bundle is supported by the column wall. Preferably the downcomers (13) of the upper tray rest upon the tops of the downcomers (13) of the next lower tray. The two crescent-shaped terminal decking sections (19) on opposite edges of the tray are supported from below by arch-shaped structures (17) anchored to the next lower tray.

Abstract: A catalyst system comprising a physical mixture of particles of a non-acidic large-pore zeolite containing a platinum-group metal and particles comprising a refractory inorganic oxide which is metal-free is effective for the reforming of a hydrocarbon feedstock. Reforming of paraffinic feedstocks to effect aromatization, particularly of a raffinate from aromatics extraction, provides improved activity in producing gasoline-range products when using the catalyst system of the invention.

Abstract: An improved catalyst and process are disclosed for the selective disproportionation of toluene. The process uses a zeolitic catalyst which is oil-dropped in an aluminum phosphate binder and has an X-ray diffraction pattern showing characteristic intensities at specified Bragg angles. Optionally, the catalyst is selectively precoked prior to toluene disproportionation. The catalyst and process provide improved selectivity for the production of paraxylene.

Abstract: A process for the conversion of plastic to produce a synthetic crude oil by means of separating a liquefied plastic into a lower boiling fraction and a higher boiling fraction containing non-distillable particulate matter which is admixed with a hydrocarbonaceous recycle stream and filtered. The filtered stream having a reduced concentration of finely divided particulate matter and the distillable lower boiling stream together with hydrogen is contacted with a hydro-demetallization catalyst in a hydro-demetallization zone. The effluent from the hydro-demetallization zone is contacted with a hydrocracking catalyst in a hydrocracking zone to produce lower boiling hydrocarbons suitable for use as a synthetic crude oil and to produce gaseous, water-soluble inorganic compounds. A recovered hydrogen-rich gaseous stream is preferably recycled to the hydro-demetallization zone. The gaseous, water-soluble inorganic compounds are removed by scrubbing the hydrocracking zone effluent with an aqueous stream.

Abstract: A reactivation process is disclosed for a catalyst formulated to selectively upgrade naphtha to obtain an isoparaffin-rich product for blending into gasoline. The process utilizes a solid strong-acid catalyst comprising an anion-modified metal oxide, preferably comprising a sulfated support of an oxide or hydroxide of a Group IVB (IUPAC 4) metal, and a platinum-group metal component.

Abstract: A novel catalyst and the use thereof in a reforming process is disclosed. The catalyst comprises a refractory inorganic oxide, platinum-group metal, Group IVA(IUPAC 14) metal, indium and lanthanide-series metal. Utilization of this catalyst in the conversion of hydrocarbonsaromatics product.

Abstract: An improved process is disclosed for the selective disproportionation and transalkylation of toluene. The process uses a zeolitic catalyst, preferably comprising a binder, containing a weak metal in a defined reduced state which is believed to provide Lewis acidity in the catalyst. The catalyst and process provide improved selectivity for the production of paraxylene.

Abstract: Improved product purity is provided in a simulated moving bed adsorptive separation apparatus by flushing the stagnant volume of the feed valve and the transfer line connecting the feed valve to the rest of the apparatus. The invention adds another line for delivering recycle fluid as the flush stream to an additional inlet port on the feed valve. The apparatus comprises a number of serially connected adsorbent-containing chambers. The chambers are linked together with valving necessary to simulate the continuous countercurrent flow of the adsorbent and liquid phases.

Abstract: 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.

Abstract: The residue (bottoms) from a vacuum or atmospheric column is upgraded in a revamped multireactor hydrotreating zone. The hydrotreating zone is modified such that the entire effluent of the next to last reactor is withdrawn, light gases and hydrocarbons are removed from the effluent in separators and the remaining liquid is passed into a fractionation column and/or a carbon rejection zone. Gas oils and distillates from the column and/or carbon rejection zone are then returned to the last reactor of the hydrotreating zone.

Abstract: High vapor and liquid capacity counterflow fractionation trays demonstrating superior turndown and performance characteristics include a number of parallel downcomers separated by planar tray decking having unique bidirectional slotted cap valve geometries. Several different arrangements of the bidirectional valves are presented. The raised trapezoids of the bidirectional valves may be arranged in two groups which each face the nearest downcomer, or arranged in lines parallel to the downcomer sidewalls such that trapezoids of neighboring rows face opposite directions. In a third embodiment these bidirectional slotted cap valves are only located in the regions of the decking sections located next to the downcomers.

Abstract: A hydrocarbon feedstock is catalytically reformed in a sequence comprising a first bifunctional-catalyst reforming zone, a zeolitic-reforming zone containing a catalyst comprising a platinum-group metal and a nonacidic zeolite, and a terminal bifunctional catalyst reforming zone. The first and terminal bifunctional catalysts preferably comprise a lanthanide-series metal component. The process combination permits higher severity, higher aromatics yields and/or increased throughput relative to the known art, and is particularly useful in connection with moving-bed reforming facilities with continuous catalyst regeneration.

Abstract: A hydrocarbon feedstock is catalytically reformed in a sequence comprising a continuous-reforming zone, consisting essentially of a moving-bed catalytic reforming zone and continuous regeneration of catalyst particles, and a zeolitic-reforming zone containing a catalyst comprising a platinum-group metal and a nonacidic zeolite. The process combination permits higher severity, higher aromatics yields and/or increased throughput in the continuous-reforming zone, thus showing surprising benefits over prior-art processes, and is particularly useful in upgrading existing moving-bed reforming facilities with continuous catalyst regeneration.

Abstract: The chiral isomers of 3-hydroxytetrahyrofuran are separated by means of liquid chromatography using a stationary phase comprising a substituted polysaccharide carbamate. The separation may be performed using a simulated moving bed adsorbent system. Suitable mobile phase materials comprise a mixture of a light paraffin and a low molecular weight aliphatic alcohol such as a mixture of n-hexane and ethanol. Amylose is the preferred polysaccharide.

Abstract: The feedstock to an aromatization process is processed by a selective adsorption step to remove hydrocarbon species, particularly indan, which have a severe adverse effect on aromatization catalyst stability. The feedstock preferably is a paraffinic raffinate from aromatics extraction. The intermediate from the adsorption step is particularly suitable for the selective conversion of paraffins to aromatics using a high-activity dehydrocyclization catalyst with high aromatics yields and long catalyst life.

Abstract: The adsorbent bed (25) retained in an HPLC column (1) is maintained in a constant state of compression by a spring loaded hydraulically active second column (13). A relatively small spring (14) loaded piston (15) in the second column maintains a constant hydraulic pressure in the hydraulic chamber (3) of the larger diameter HPLC column (1). Multiple small diameter columns (13) can be employed if necessary.

Abstract: Economies in capital cost and operation of a hydrocarbon refining unit for desulfurization of diesel fuel are provided by a heat exchange sequence which eliminates the need for a fired heater on the product fractionation zone. The feed to the fractionation zone is heat exchanged twice against both the effluent bottoms stream of the fractionation zone and the reaction zone effluent stream.

Abstract: The capacity of a simulated moving bed adsorptive separation process is increased by flushing the contents of the transfer line just previously used to remove the raffinate stream from the adsorbent chamber back into the adsorbent chamber. This step is performed immediately upstream of the point of raffinate withdrawal. Preferably the feed stream to the process is used as the flushing liquid. This flush step eliminates the passage of a quantity of the raffinate material into the adsorbent chamber when the process conduit is subsequently used to charge the feed stream to the adsorbent chamber.

Abstract: A large hydrocracking feed stream is processed without resorting to full dual reaction trains by passing a portion of the feed stream into each of two reaction zones, with the effluents of the two reaction zones being charged into a common separation and product recovery facility. Unconverted hydrocarbons recovered in the product recovery facility are passed into only one of the reaction zones.

Abstract: Metaxylene is recovered from admixture with other C.sub.8 aromatic hydrocarbons including orthoxylene by liquid phase adsorptive separation using a sodium exchanged Y zeolite as the adsorbent. Performance is improved by maintaining the adsorbent in a narrow range of temperature and hydration. These conditions allow the metaxylene to be recovered in a single raffinate process without costly prefractionation for orthoxylene removal. A novel desorbent, indane, is also disclosed.