Abstract: A shell and tube heat exchanger reactor with forced circulation is used to improve heat and mass transfer for exothermic liquid-liquid, gas-liquid and gas-liquid-solid reactions. Enhanced productivity and selectivity are obtained.

Abstract: The invention comprises particle loader assembly for loading particles into a vessel to form a particle bed comprising inner and outer radially disposed concentric layers of particles said inner layer containing at least one type of particle of different granulometry or composition or both granulometry and composition from a type of particle contained in said outer layer.

Abstract: The invention comprises an annular hollow fiber membrane module comprising a plurality of helically wound layers of semi-permeable hollow fibers, wherein the fiber wind angle varies across the axial length of the module in one or more layers. In a preferred embodiment, the module has at least one tubesheet region and an active region, and the wind angle in the tubesheet region of the module differs from the wind angle in the active region of the module. A method of making the module, and a separation module which includes the module described above is also disclosed.

Abstract: Ions (e.g. lithium) can be removed or recovered from brines containing those ions and optionally one or more other ions (e.g. other alkali metal ions) by the use of a temperature-swing, ion-exchange process and apparatus employing an ion-exchange material. The process and apparatus depends on a change in the selectivity coefficient of an ion exchange material for the ions desired to be recovered with a change in temperature, resulting in desirable ions being relatively selectively released at one temperature and undesirable ions being relatively selectively released at another temperature. The process of the invention can be used to effect the separation of any ion (or set of ions) from another ion or from a set of ions wherein the selectivity coefficient for one ion (or set of ions) has a substantial temperature dependence, compared to that for the other ion (or set of ions).

Abstract: An adsorption process and system for the selective adsorption of a more readily adsorbable component, such as nitrogen, as from air or other feed gas mixture is carried out using a composite adsorbent bed containing different adsorbent materials positioned in separate zones in which the temperature conditions favor adsorption performance of the particular adsorbent material under applicable processing conditions in each zone. A method for the selection of the adsorbent materials is based on Adsorption Figure of Merit values.

Abstract: A cryogenic cooling tower in which a process liquid from which heat is to be removed is supplied to the tower interior that has a plurality of plates vertically stacked one above the other, alternating in opposite directions and tilted downwardly at an angle relative to the tower vertical axis. A cryogenic cooling medium is supplied to the tower interior. The process liquid forms a film on the upper surface of the plate and drops from its front end to the next lower plate. While on a plate the process liquid spread into a film provides a greater surface area to react with the cooling medium to effect the heat transfer. The tilt angle of the plates can be adjusted to control the residence time of the process liquid in the tower.

Abstract: An endogenerator is provided in which CO and H.sub.2 are generated as primary products of hydrocarbon oxidation. Noble metal catalysts such as platinum (Pt) and particularly rhodium (Rh), are loaded on a porous ceramic support, of example, an alumina carrier. In the endogenerator reactor little or no CO and H.sub.2 are produced by the slow and energy-intensive reforming reactions and this allows for a compact reactor which operates autothermally without auxiliary heating means, and with high space velocities wherein space velocity is defined as the number of standard cubic feet per hour of output gas per cubic foot of the catalyst carrier. Preferred hydrocarbons are methane or propane, preferred oxidants are nitrogen/oxygen mixtures with from 5% oxygen up to 100% oxygen. The endogenerator of the present invention provides a process and apparatus that generates the required reducing gases CO and H.sub.2 for heat treating applications which require leaner atmospheres and lower carbon potentials.

Abstract: The invention comprises a PSA gas prepurifier for the removal of contaminants present in a feed gas stream. The prepurifier of the invention has a bed of adsorbent material which comprises at least two discrete layers of adsorbents, at least one of the adsorbents being comparatively strong and at least another of the adsorbents being comparatively weak.

Abstract: Multiple thermal pulses are employed to regenerate segments of an adsorber bed simultaneously in thermal swing adsorption processes. The invention is particularly applicable to air purification as it helps to reduce purge flow and improve regeneration efficiency.

Abstract: A vessel for use in a pressure swing adsorption gas separation process includes an enclosing wall which defines an enclosed space having a top region and a bottom region. An annular adsorbent bed is positioned within the enclosed space and has a porous outer wall, a porous inner wall and adsorbent material positioned between the walls. The porous outer wall is separated from the enclosing wall to create a gas feed channel therebetween, and the porous inner wall surrounds an inner tank whose wall surface is separated from the porous inner wall and creates a product flow channel therebetween. A gas feed/distribution baffle structure is positioned in the bottom region of the vessel and in fluid communication with the gas feed channel to provide a gas feed thereto. The gas feed enters the gas feed channel and the adsorbent bed via the porous outer wall and in a direction generally radially towards the inner porous wall and product flow channel.

Abstract: A PSA method incorporating the invention is applicable to the separation of a preferred gas from a mixture of the preferred gas and a less preferred gas. The PSA method uses an adsorbent bed including one or more layers of O.sub.2 equilibrium selective adsorbents, and comprises the steps of: pressurizing the adsorbent bed to a high pressure with a feed of air to enable the adsorbent bed to adsorb O.sub.2 ; extracting from the bed at bed pressure, a flow of N.sub.2 and storing at least some of the flow in a product tank; desorbing O.sub.2 from the adsorbent bed by feeding void gas in the bed enclosure to a storage tank and venting the adsorbent bed to a low pressure region; purging the adsorbent bed by feeding thereto the void gas from the storage tank; and repressurizing the adsorbent bed to an intermediate pressure with a flow of void gas from the storage tank.

Abstract: Improved anisotropic fluid separation membranes are prepared from blends of polymers with surface energy differences. The membranes are formulated by processes wherein low surface energy polymer with desirable fluid separation and permeation characteristics is preferentially concentrated in the surface discriminating layer of the membrane.

Abstract: A method and system for separating one or more components from gas mixtures uses a moving bed of adsorption material particles under continuous and substantially isobaric pressure conditions. Contaminated gases are likewise purified by removing one or more contaminants therefrom using such a moving bed of adsorption material particles under continuous and substantially isobaric pressure conditions.

Abstract: Novel polyimide gas separation membranes and the process of using such membranes to separate gases are disclosed. The polyimides are formed from rigid aromatic dianhydrides and aromatic diamines that contain sulfonic acid, salified sulfonic acid, or sulfonic ester groups. Methods of preparing improved composite gas separation membranes from the sulfonated polyimides of this invention are disclosed.

Abstract: A pressure swing process for air separation to produce concentrated gaseous oxygen at an elevated pressure without the requirement of further compression of the gaseous oxygen product. The process comprises the steps of compressing the feed air to a pressure in the range of approximately 45 psig to 105 psig, preheating the feed air to each of the adsorption beds to a temperature in the range of approximately 100.degree. F. to 200.degree. F., then directing flow of the feed air cyclically into and through at least two crystalline zeolite molecular sieve adsorption beds for selectively adsorbing at least nitrogen therein. In this manner, oxygen having a purity of approximately 88% to 93% at a recovery of approximately 30% to 45% and a bed size factor in the range of 2,500 pounds to 4,000 pounds of adsorbent per ton per day of oxygen can be delivered to a receptor tank at an elevated pressure of approximately 40 psig to 100 psig.

Abstract: Membrane separation methods and systems separate gaseous mixtures into purified component gases thereof. Purified oxygen gas (60-90% purity), for example, may be derived from ambient air in an efficient manner. Systems and methods are provided by which at least three permeator stages are used while requiring less than one compressor per stage. Energy requirements are reduced and product purity as a function of energy requirements is improved.

Abstract: Vacuum pressure swing adsorption (VPSA) processing is carried out employing a processing sequence of ten steps that serves to enhance the productive capacity thereof for air separation and other desirable applications.

Abstract: The invention involves annular hollow fiber membrane bundle comprising a plurality of helically wound layers of semi-permeable hollow fibers helically wound thereon and at least one reinforcement filament which has been helically wound concurrently with said hollow fibers into the hollow fiber membrane bundle. A preferred embodiment provides that the reinforcement filament is uniformly distributed throughout the diameter of the bundle and/or across the axial length of the bundle. Though, other embodiments provide a non-uniform distribution throughout the diameter of the bundle and/or across the axial length of the bundle.

Abstract: The production of terephthalic acid by the oxidation of p-xylene is carried out in such a manner that the oxygen concentration in the liquid phase is maximized through the use of pure or nearly pure oxygen, while simultaneously the hydrocarbon feed concentration is minimized through rapid dilution with the reactor contents.

Abstract: Ions (e.g. lithium) can be removed or recovered from brines containing those ions and optionally one or more other ions (e.g. other alkali metal ions) by the use of a temperature-swing, ion-exchange process employing an ion-exchange material. The process depends on a change in the selectivity coefficient of an ion exchange material for the ions desired to be recovered with a change in temperature, resulting in desirable ions being relatively selectively released at one temperature and undesirable ions being relatively selectively released at another temperature. The process of the invention can be used to effect the separation of any ion (or set of ions) from another ion or from a set of ions wherein the selectivity coefficient for one ion (or set of ions) has a substantial temperature dependence, compared to that for the other ion (or set of ions).