Abstract: The present invention pertains to a process for manufacturing a fluoropolymer membrane, said process comprising the following steps: (i) providing a composition [composition (C)] comprising, preferably consisting of: at least one fluoropolymer [polymer (F)], a water-soluble liquid medium [medium (Mws)] comprising, preferably consisting of at least one solvent selected from the group consisting of diesters of formula (I-de), esteramides of formula (I-ea) and diamides of formula (I-da); R1 (O?)CO-Ade-OC(?O)R2 (I-de) R1O(O?)C-Aea-C(?O)NR3R4 (I-ea) R5R6N(O?)C-Ada-C(?O)NR5R6 (I-da) wherein: R1 and R2, equal to or different from each other, are independently selected from the group consisting of C1-C20 hydrocarbon groups; R3, R4, R5 and R6, equal to or different from each other, are independently selected from the group consisting of hydrogen, C1-C36 hydrocarbon groups, possibly substituted, being understood that R3, R4, R5 and R6 might be part of a cyclic moiety including the nitrogen atom to which they are bound,

Abstract: A process for the recovery of sodium sulfate from water, in particular from water deriving from a silica manufacturing process.

Abstract: A process for the recovery of sodium sulfate from water, in particular from water deriving from a silica manufacturing process.

Abstract: The present invention pertains to a process for manufacturing a fluoropolymer membrane, said process comprising the following steps: (i) providing a composition [composition (C)] comprising, preferably consisting of: at least one fluoropolymer [polymer (F)], a water-soluble liquid medium [medium (Mws)] comprising, preferably consisting of at least one solvent selected from the group consisting of diesters of formula (I-de), esteramides of formula (I-ea) and diamides of formula (I-da); R1 (O?)CO-Ade-OC(?O)R2 (I-de) R1O(O?)C-Aea-C(?O)NR3R4 (I-ea) R5R6N(O?)C-Ada-C(?O)NR5R6 (I-da) wherein: R1 and R2, equal to or different from each other, are independently selected from the group consisting of C1-C20 hydrocarbon groups; R3, R4, R5 and R6, equal to or different from each other, are independently selected from the group consisting of hydrogen, C1-C36 hydrocarbon groups, possibly substituted, being understood that R3, R4, R5 and R6 might be part of a cyclic moiety including the nitrogen atom to which they are bound,

Abstract: Hydrophobic, asymmetric membranes are formed integrally from elastomeric polymers. The membranes have a dense, discriminating layer and a thick, porous support layer and require no other support. The membranes of the invention provide an economic advantage over prior art composite membranes used for separating target organics from a mixture. Using the methods of the invention it is possible to separate two or more organic components wherein discrimination is made on the basis of molecular size.

Abstract: Hydrophobic, asymmetric membranes are formed integrally from elastomeric polymers. The membranes have a dense, discriminating layer and a thick, porous support layer and require not other support. The membranes of the invention provide an economic advantage over prior art composite membranes used for separating target organics from a mixture.

Abstract: Using the methods of the invention, an elastomeric polymer is dissolved in a suitable solvent, cast in one of the membrane casting techniques using a phase inversion technique, and immersed in a coagulation bath comprised of suitable solvent/non-solvent pairs (e.g., THF/water and ethanol). Asymmetric membranes having a dense discriminating layer and a thicker porous support layer suitable for application in pervaporation processes were obtained in a single step. An increase of the polymer concentration in the casting solution gives a more dense layer. When cast as formed using the methods of the invention, the membrane obtained is an integrally skinned membrane comprising a thin, dense separation layer over a porous support layer (asymmetric membrane) formed in a single casting operation. The resulting membrane is homogenous with respect to chemical composition.

Abstract: Hydrophobic, asymmetric membranes are formed integrally from elastomeric polymers. The membranes have a dense, discriminating layer and a thick, porous support layer and require not other support. The membranes of the invention provide an economic advantage over prior art composite membranes used for separating target organics from a mixture.

Abstract: Porous membranes of (per)fluorinated amorphous polymers having a porosity in the range 5-500 nm, preferably 20-100 nm, measured by an atomic force electronic microscope; the membrane pore average size distribution being narrow, about 80%-90% of the pores have a size ranging from minus 5 nm to plus 5 nm of the value of the distribution maximum peak.

Abstract: Amorphous fluoropolymer selfsupported manufactured articles obtained by casting from solution in a single step, characterized in that they are obtained by the polymerization of a structure (I), optionally and preferably with a monomer having a structure (II): CF2=CY1Y2  (II) wherein: Rf is a C1-C5 perfluoroalkyl radical; X1 and X2 are selected from F and CF3; Y1 and Y2 are selected from F, Cl, H, CF3, ORf; having refractive index lower than 1.35, transmittance higher than 90% in the radiation field 300-2,000 nm wave length, and thickness higher than 20-25 &mgr;m.

Abstract: Amorphous fluoropolymer selfsupported manufactured articles obtained by casting from solution in a single step, characterized in that they are obtained by the polymerization of a structure (I), optionally and preferably with a monomer having a structure (II): 1  CF2=CY1Y2  (II)

Abstract: A ceramic catalytic membrane reactor for the separation of hydrogen and/or isotopes thereof from fluid, in particular gaseous flows, formed of a tubular support (1) made of a porous ceramic material, which is coated with layers (4) of a gas-tight material at both ends thereof, and with a thin layer or film (2) of a metal or metal alloy having catalytic activity and selective permeability to hydrogen and isotopes thereof, such as Pd or Pd/Ag, on a central portion thereof, where the reaction takes place. The central portion is provided with heating. The seals (6) of the membrane reactor are located on the two gas-tight ends of the tubular support (1).

Abstract: The present invention relates to a process for preparing polypiperazinamide-based reverse-osmosis membranes comprising:(a) preparing a solution of polypiperazinamide in a polar organic solvent;(b) applying the solution on a planar support so as to form a planar body;(c) evaporating the solvent under the action of a flow of air, said air flow having, with respect to said planar support, such a speed as to produce Reynolds numbers between 5 and 100;(d) gelling the planar body by phase reversal by passing through a coagulation bath to form the membrane; and(e) washing the membrane to extract the solvent contained therein. The entire process is carried out at a temperature lower than about 30.degree. C.The invention allows the production of reverse-osmosis membranes with high flow and high mechanical characteristics.