This invention relates to a novel conductive organic membrane-coupled filtration system for the degradation of organic pollutants from wastewater. The system comprises a connected water pump and a reactor. The upper end of the reactor contained a water inlet, and the lower end consisted of a water outlet. A counter electrode and a membrane electrode are fixed on the reactor between the water inlet and water outlet. The counter electrode and membrane electrode constitute a two-electrode system connected to an external potentiostat through metal wires. The membrane electrode is made of carbon-based polyvinylidene fluoride (PVDF) membrane that can be used to enhance the electrochemical separation of small molecules and the removal of organic pollutants.

M(SiF.sub.6)(pyz).sub.3 (M=Cu, Zn, Co, or Ni) has a pore size between a size of H.sub.2 and a size of CO.sub.2, and thus exhibits prominent screening performance for H.sub.2/CO.sub.2. A strong interaction between Cu(SiF.sub.6)(bpy).sub.2 and a CO.sub.2 molecule can hinder the transport of the CO.sub.2 molecule. The above two MOFs both can achieve the H.sub.2/CO.sub.2 separation. By preparing a dense MSiF.sub.6/polymer layer, MSiF.sub.6 is uniformly dispersed in the polymer and is fixed, and subsequently, MSiF.sub.6 is converted into M(SiF.sub.6)(pyz).sub.3 or Cu(SiF.sub.6)(bpy).sub.2 by interacting with an organic ligand. Through vapor-induced in-situ conversion, MOF particles can be well dispersed without interface defects between the MOF particles and the polymer. Even at a doping amount of 80%, the mechanical flexibility and stability of the MMM can still be retained.

A virus removal membrane includes cellulose, and a primary-side surface through which the protein-containing solution is to be applied and a secondary-side surface from which a permeate that has permeated the virus removal membrane is to be flowed, wherein a bubble point is 0.5 MPa or more and 1.0 MPa or less; and when a solution containing gold colloids having a diameter of 30 nm is applied through the primary-side surface to the virus removal membrane to allow the virus removal membrane to capture the gold colloids for measurement of brightness in a cross section of the virus removal membrane, a value obtained by dividing a standard deviation of a value of an area of a spectrum of variation in the brightness by an average of the value of the area of the spectrum of variation in the brightness is 0.01 or more and 0.30 or less.

A hollow-fiber membrane according to an aspect of the present disclosure contains a polytetrafluoroethylene or a modified polytetrafluoroethylene as a main component and has an average outer diameter of 1 mm or less and an average inner diameter of 0.5 mm or less. In a measurement of a heat of fusion of the polytetrafluoroethylene or the modified polytetrafluoroethylene with a differential scanning calorimeter, when the polytetrafluoroethylene or modified polytetrafluoroethylene is subjected to a first step of heating from room temperature to 365° C., a second step of cooling from 365° C. to 350° C., maintaining the temperature, subsequently cooling from 350° C. to 330° C., and further cooling from 330° C. to 305° C., and a third step of cooling from 305° C. to 245° C. at a rate of −50° C./min and subsequently heating from 245° C. to 365° C. at a rate of 10° C./min, a heat of fusion from 296° C. to 343° C. in the third step is 30.0 J/g or more and 45.0 J/g or less.

A microporous membrane is made by a dry-stretch process and has substantially round shaped pores and a ratio of machine direction tensile strength to transverse direction tensile strength in the range of 0.5 to 5.0. The method of making the foregoing microporous membrane includes the steps of: extruding a polymer into a nonporous precursor, and biaxially stretching the nonporous precursor, the biaxial stretching including a machine direction stretching and a transverse direction stretching, the transverse direction stretching including a simultaneous controlled machine direction relax.

A method for preparing a SiO.sub.2-polyethersulfone conductive ultrafiltration membrane and the ultrafiltration membrane comprises hydrophilic CF cloth as the conductive membrane base, which provides an effective carrier for the preparation of a stable and efficient conductive membrane. After pretreatment, the silica solution was combined with the membrane via film scraping. Then phase catalysis and polymerization of PES onto the film obtained the final silica dioxide-polyethersulfone conductive ultrafiltration membrane. The silica solution was applied in the form of a coating on the hydrophilic CF cloth, in which silicon dioxide combined with the hydrophilic CF cloth, avoiding electrochemical interference. The modified hydrophilic CF cloth improved the hydrophilicity of the conductive film, with silica firmly attaching to PES and improving the stability of the SiO.sub.2-polyethersulfone conductive ultrafiltration membrane. After 8 cycles of reuse, the performance of the membrane remained stable.

A zeolite membrane and a preparation method thereof are provided. The method includes: adding an organic binder solution dropwise to zeolite, and thoroughly grinding and stirring; blade-coating a resulting mixture on a substrate at a given thickness; and drying to obtain the zeolite membrane. The preparation of a zeolite membrane does not require a complicated hydrothermal crystal growth process, and the membrane can be prepared directly from natural zeolite or artificial zeolite. A prepared zeolite membrane has the characteristics of simple preparation process, low cost, prominent water permeability, high contaminant rejection rate and high zeolite load. The zeolite membrane, when used for the rejection of contaminants in water, can not only remove macromolecular contaminants in water, but also efficiently remove ammonia nitrogen by way of ion exchange, which is suitable for advanced treatment of wastewater.

Provided is a method for preparing a defect-free DDR molecular sieve membrane. Sigma-1 molecular sieve is used as an inducing seed crystal to prepare and obtain a continuous and compact DDR molecular sieve membrane on the surface of a porous ceramic support. An ozone atmosphere or an external field assisted technology is used to remove a template in the pores of the molecular sieve membrane at a low temperature. The invention avoids the formation of intercrystal defects and cracks, an activated DDR molecular sieve membrane has a good selectivity for separating CO2, and the membrane preparation time is significantly reduced.

A cross-linked polyimide of the reaction product of a crosslinking agent and a polyimide. The cross-linking agent having at least two cross-linking moieties and the polyimide has a plurality of polyimide chains having an aryl constituent with a moiety comprised of a reactive substituent. The polyimide has crosslinks from the reaction of the reactive substituent of the aryl constituents of the polyimide chains and the cross-linking moieties of the cross-linking agent. The cross-linking may be induced by thermally treating a mixture of the polyimide and crosslinking agent above about 150° C. to a temperature where the polyimide begins to decompose under an inert atmosphere. The membrane can be used for separations involving gases such as hydrogen and light hydrocarbons.

The present invention relates to an ultrathin-film composite membrane based on a thermally rearranged poly(benzoxazole-imide) copolymer and a production method therefor and to a technique for forming a porous support by means of a thermally rearranged poly(benzoxazole-imide)copolymer and then producing, on the porous support, an ultrathin-film composite membrane comprising a thin-film active layer. The ultrathin-film composite membrane produced according to the present invention has excellent thermal/chemical stability and mechanical physical properties, thus is not only capable of withstanding high operating pressure, but also capable of minimizing internal concentration polarization and thereby obtaining high water permeance and, as a result, high power density, and thus can be applied to a pressure-retarded osmosis or forward osmosis process. Further, said ultrathin-film composite membrane has excellent chemical/thermal stability against organic solvents, has superior organic solvent nano-filtration performance, particularly maintains nano-filtration performance stably even under a high-temperature organic solvent condition, and thus can be applied as an organic solvent nano-filtration membrane.