The invention relates to a process for preparing an ester by alkoxycarbonylation of a C2 to C20 hydrocarbon having at least one multiple bond, preferably having at least one olefinic double bond, in which the homogeneous catalyst system used is separated from the product mixture by means of membrane separation and recycled into the reaction zone. In a development of the present invention, the ester thus formed is converted into another ester by transesterification.

The invention relates to a process for preparing carboxylic acids or salts thereof by hydrolysis or saponification of an ester, which is obtained by alkoxycarbonylation of a C2 to C20 hydrocarbon having at least one multiple bond, preferably having at least one olefinic double bond, in which the homogeneous catalyst system used is separated from the product mixture by means of membrane separation. In a development of the present invention, the ester thus formed is converted into another ester by transesterification and then hydrolyzed or saponified.

A system for extracting ions from an aqueous solution without utilizing ion exchange. A semi-permeable membrane with 0.1 to 1000 nm diameter pores separates an aqueous salt solution from a chelating gel. The gel has un-crosslinked polymer (e.g. 1-10% by weight) and the balance water. The semi-permeable membrane lets ions diffuse into the chelating gel where the ions become trapped. The gel has a molecular weight that prevents its diffusion through the semi-permeable membrane.

The invention relates to the field of membrane gas separation. A method of removing components of gas mixtures which is based on passing the components of a gas mixture through a nanoporous membrane and subsequently selectively absorbing them with a liquid absorbent that is in contact with the nanoporous membrane, wherein to prevent the gas from getting into the liquid phase of the absorbent and the liquid phase of the absorbent from getting into the gas phase, a nanoporous membrane with homogeneous porosity (size distribution less than 50%) and a pore diameter in the range of 5-500 nm is used, and the pressure differential between the gas phase and the liquid absorbent is kept below the membrane bubble point pressure. An acid gas removal performance of more than 0.3 nm.sup.3/(m.sup.2 hour) in terms of CO.sub.2 is achieved at a hollow-fiber membrane packing density of up to 3200 m.sup.2/m.sup.3, which corresponds to a specific volumetric performance of acid gas removal of up to 1000 nm.sup.3 (m.sup.3 hour). The technical result is that of providing effective extraction of undesirable components from natural and process gas mixtures.

A platform has a filter system with a first set of filter modules and a second set of filter modules that is different from the first set of filter modules. Each set of filter modules includes an inflow channel and an outflow channel. A fluid inlet is connected to the first set of filter modules, a fluid outlet is connected to the second set of filter modules, and a separation interface separates the first and second sets of filter modules. The separation interface has a first interface channel to connect to the module outflow channel of the first set of filter modules, and a second interface channel to connect to the module inflow channel of the second set of filter modules. The filter system receives fluid through the fluid inlet and, after the fluid has passed through each set of filter modules, discharges the fluid through the fluid outlet.

A carbon dioxide absorption medium. The absorption medium includes a plurality of hollow fibers and a plurality of binder particles. The hollow fibers have walls comprising a selectively permeable membrane that is configured to permit passage of gaseous carbon dioxide but not liquids. The plurality bind particles are dispersed between the hollow fibers and comprise an absorbent material configured to absorb gaseous carbon dioxide and to bind the carbon dioxide in a solid state.

A reaction assembly separating plant material from water includes a first annular filter element defining an axis. The first annular filter element is defined by an outer annular coil of flat wire and an optional second filter element is defined by an inner annular coil of flat wire, being generally helical in the axial direction. A cylindrically or frustoconical filter membrane is concentrically disposed between the first and second annular filter element. The filter membrane is porous having aperture size of less than a nano-particulate size of the plant material, but greater than a nano-particulate size of the water molecule. The second annular filter includes adjustable porosity for selectively preventing particles from reaching the filter membrane and selectively cleaning the membrane by reversed flow of water through the membrane. The assembly generates radial and distal flows and differential pressure forces, for use in high throughput industrial, agricultural and municipal facilities.

Disclosed herein is a unit for ultrafiltration and purification (1) of a product stream (3) containing a biological macromolecular product as well as a substance to be separated from the product stream, comprising at least one capillary ultrafiltration module (2), characterized in that at least one pump (4) conveys the product stream into the capillaries of the at least one capillary ultrafiltration module, at least one positive displacement pump (5) conveys the product stream from the capillaries and at least one further pump (6) passes a washing fluid (9) over the outside of the capillaries, the unit includes no measure for circulating the product stream and the washing fluid into the ultrafiltration module, as well as
at least one guard filter (8), through which all fluid leaving the at least one capillary ultrafiltration module in the direction of the product stream is passed.

A fluorinated aromatic sulfone polymer [polymer (F-PS)] comprising: recurring units [units (A)] derived from at least one dihalo-diaryl sulfone [monomer (A)]; recurring units [units (B)] derived from at least one aromatic diol [monomer (B)]; at least one unit [units (PFPE)] derived from at least one fully or partially fluorinated polyether alcohol (PFPE alcohol), said polymer (F-PS) having a fluorine content ranging from 0.1% to 10% wt, is herein disclosed. Films and membranes obtained from (F-PS) are also disclosed, as well as their use in filtration methods.

In various aspects, methods and apparatuses for liquid-liquid extraction are provided. In certain aspects, an emulsion can be formed by combining a feed stream, an extractant, and a surfactant. The feed stream comprises a plurality of distinct components including a first component to be removed therefrom. The feed stream may be selected from a group consisting of: a hydrocarbon feed stream and an azeotrope. Then, a portion of the first component is extracted from the feed stream (or emulsion) by contact with a superoleophobic and hygroscopic membrane filter that facilitates passage of the first component and extractant through the superoleophobic and hygroscopic membrane filter. A purified product is collected having the portion of the first component removed. Such methods are particularly useful for refining fuels and oils and separating azeotropes and other miscible component systems. Energy-efficient, continuous single unit operation apparatuses for conducting such separation techniques are also provided.