Ausimont S.p.a.

Rhodia Operations

Solvay Specialty Polymers Italy S.p.a.

The United States of America As Represented by the Administrator of the U.S. Environmental Protection Agency

U.S. Environmental Protection Agency

Separem S.p.a.

Enrico Drioli

Vincenzo Arcella

Patrizia Serenella Maccone

Subhas K Sikdar

John O Burckle

Binay K Dutta

Alberto Figoli

Aldo Sanguineti

Young Moo Lee

Dominique Horbez

Emanuele Di Nicolo′

Suk Young Lee

Amalia Gordano

Giuseppina Grippaldi

Naser Tavajohi Hassankiadeh

Marco Sogliano

Soccorso Gaeta

Zhaoliang Cui

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 (M)] comprising, preferably consisting of at least one solvent selected from the group consisting of diesters of formula (I-), esteramides of formula (I-) and diamides of formula (I-); R(O&#x2550;)CO-A-OC(&#x2550;O)R(I-) RO(O&#x2550;)C-A-C(&#x2550;O)NRR(I-) RRN(O&#x2550;)C-A-C(&#x2550;O)NRR(I-) wherein: Rand R, equal to or different from each other, are independently selected from the group consisting of C-Chydrocarbon groups; R, R, Rand R, equal to or different from each other, are independently selected from the group consisting of hydrogen, C-Chydrocarbon groups, possibly substituted, being understood that R, R, Rand Rmight be part of a cyclic moiety including the nitrogen atom to which they are bound, said cyclic moiety being possibly substituted and/or possibly comprising one or more than one additional heteroatoms, Ais a C-Cdivalent alkylene group comprising one or more ether oxygen atoms, Aand A, equal to or different from each other, are independently C-Cdivalent alkylene groups, optionally comprising one or more ether oxygen atoms and/or one or more functional side groups; (ii) processing the composition (C) at a temperature of at least 100&#xb0; C. thereby providing a film; (iii) cooling the film provided in step (ii) to a temperature below 50&#xb0; C.; (iv) contacting the film provided in step (iii) with a non-solvent medium [medium (M NS)] thereby providing a fluoropolymer membrane; and (v) optionally, drying the fluoropolymer membrane provided in step (iv).

Process for manufacturing fluoropolymer membranes

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

Process for the recovery of sodium sulfate

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.

Method for fabrication of elastomeric asymmetric membranes from hydrophobic polymers

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.

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.

Membranes of (per)fluorinated amorphous polymers

Amorphous fluoropolymer manufactured articles

The present invention relates to a process for preparing polypiperazinamide-based reverse-osmosis membranes comprising:

Process for preparing reverse-osmosis membrane, and membrane obtained

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Naples, Italy

Enrico Drioli