1369 results about "Pervaporation membrane" patented technology

The invention discloses a preparation method and an application of an anti-pollution hydrophilic separating membrane. The preparation method is characterized in that a pyrocatechol derivative is used as an accelerant and a curing agent between a separating membrane material and a hydrophilic material, when blending casting film liquid of the separating membrane is prepared, the pyrocatechol derivative is added to blending liquid of the separating membrane material and the hydrophilic material, and the pyrocatechol derivative is subjected to polymerization cross-linking in a phase conversion process of the membrane preparation, so that the effect of fixing the hydrophilic material is achieved. The preparation method of the anti-pollution hydrophilic separating membrane has strong universality and is suitable for the blending of multiple hydrophilic materials and multiple membrane materials. The preparation method is simple, easy to operate, mild in conditions, economic, high-efficiency, environmentally-friendly, easy for industrialization and suitable for the preparation of multi-functional hydrophilic micro-filtration membranes, ultra-filtration membranes, nano-filtration membranes, reverse-osmosis membranes, positive-osmosis membranes, pressure-delay osmosis membranes, pervaporation membranes and the like which are used for liquid and gas separation and membrane reactors.

The invention discloses a high-strength antipollution layer composite reverse osmosis membrane and a preparation method thereof. The composite reverse osmosis membrane comprises a non-woven fabric layer, a porous supporting layer and a dense polyamide layer, wherein the PVA antipollution layer with high crosslinking degree, which is formed through high-temperature crosslinking after being coated with a PVA solution and a solution containing a crosslinking agent and a catalyst in turn, is arranged on the surface of the dense polyamide layer. The composite reverse osmosis membrane increases the acting force between the antipollution layer and the dense polyamide layer and improves the strength of the PVA antipollution layer by constructing the PVA antipollution layer with high crosslinking degree on the surface of the dense polyamide layer of the prior reverse osmosis membrane so as to improve the scour resistance, the dissolution resistance and the antipollution ability of the reverse osmosis membrane and prolong the service life of the antipollution composite reverse osmosis membrane. Moreover, the composite reverse osmosis membrane also has the characteristics of easy preparation and operation, high water permeability and high salt retardation rate.

The invention relates to an ethanol-permselective PDMS/PVDF multilayered composite membrane and the preparation method, which belongs to a pervaporation membrane separation field. The multilayered composite membrane is made based on the following processes: firstly, the PVDF porous basal membrane is prepared by a two-faced wiped film of kynoar polyvinylindene fluoride (PVDF) solution on the polyester non-woven fabric support layer using submersion and sedimentation transformation method; secondly, the membrane liquid, which contains dimethyl silicone polymer (PDMS), cross linking agent and catalyst, is prepared, and the PVDF porous basal membrane is immersed in the membrane liquid for 10s-1min. Each of two sides of the PVDF basal membrane are coated with a layer of silicone base by using immersion and painting method, and then the PVDF basal membrane is dried and cross linked, and so the multilayered composite membrane is made. The existing pure PDMS membrane has bad separability to ethanol aqueous solution, and the highest separation factor is 10.8 ([EtOH] equals to 8wt percent, 30 DGE C). The multilayered symmetrical composite membrane made of the invention has an excellent ethanol-permselective property to low concentration ethanol aqueous solution (5wt percent-30wt percent), and for the ethanol aqueous solution which has a concentration of 5wt percent, the separation factor ¿” value equals to 15, and the permeation flux J equals to 450g/m²h, under the temperature of 60 DGE C.

The invention relates to a membrane cleaning agent for polyacrylamide on a reverse osmosis membrane. Acid chemical cleaning agents and alkaline chemical cleaning agents are prepared in the membrane cleaning agent, and the polyacrylamide and organic and inorganic pollutants wrapped by the polyacrylamide on the surface of the polluted reverse osmosis membrane are dissolved, dispersed, peeled and removed specifically. The membrane cleaning agent has the advantages of being easy to prepare and capable of recovering water producing flux and causing on damage to elements of the reverse osmosis membrane, and raw material can be achieved conveniently.

The invention discloses an offline cleaning and evaluating device of a reverse osmosis membrane element and an application method of the device, belonging to the technical field of water treatment. The method can be used for evaluating the performance of the reverse osmosis membrane element, typically selecting cleaning agents according to the pollutant ingredients and contents and cleaning a single reverse osmosis membrane element in off-line multi-angle and multilevel manner by means of such operations as washing by a large amount of water, reverse washing, positive washing and soaking, and in the cleaning process, the method can be used for monitoring the performance of the reverse osmosis membrane element and controlling such factors as cleaning flow rate, pressure, cleaning time and temperature, so as to improve a cleaning effect. The offline cleaning and evaluating device disclosed by the invention can be also used for evaluating and testing the performance of the agents and the reverse osmosis membrane by simulating the onsite operation conditions.

A medical device such as a controlled discharge ostomy appliance comprises a fluid filled seal for sealing around a body orifice (stoma). The fluid filled seal comprises a fluid chamber including a fluid impermeable membrane that forms a movabable wall of the fluid chamber, one or more ports communicating with the chamber; and resilient foam disposed within the fluid chamber. The foam tends to expand the chamber to seal against the body. The port controls the inlet and exhaust of fluid from the chamber, in response to movement of the body away from, or towards, the seal.

A tag or smart label including a humidity sensor, and methods of manufacturing and using the same, are disclosed. The tag or smart label includes a substrate or backplane with a battery or antenna, a humidity sensor, and an integrated circuit thereon. The integrated circuit is in electrical communication with the humidity sensor and the antenna or battery, and is configured to process a signal from the humidity sensor corresponding to the humidity level or value in the environment to be monitored, and provide or generate a signal that represents the humidity level/value. The humidity sensor includes first and second electrodes that are a predetermined distance apart, a humidity-sensitive material having one or more electrical, mechanical or chemical properties that vary as a function of the humidity level/value, and a water- and/or humidity-permeable membrane covering the humidity-sensitive material.

The invention relates to a polyether copolyamide pervaporation membrane as well as a preparation method and an application thereof, and belongs to the technical field of membrane separation. The preparation method comprises the following steps: mixing polyether copolyamide and a metal organic compound with a solvent at a certain temperature to obtain a membrane casting solution, coating a polyether sulfone composite membrane supported by nonwoven cloth with the membrane casting solution, standing for a period of time in air, and drying in a vacuum drying box for several hours to obtain the polyether copolyamide pervaporation membrane. The polyether copolyamide pervaporation membrane prepared by the method is large in permeation flux, good in separation effect, good in strength, stable in structure and suitable for removing volatile organic compounds, especially volatile ester compounds from water.

A pervaporation rectification coupled system is disclosed. A method of performing organic solvent dehydration by coupling pervaporation and rectification is also disclosed. The system and the method are especially suitable for deep dehydration of organic solvents easily forming azeotropes with water, and belong to the technical field of separation. The method includes processes of: feeding a water-containing organic solvent (with a water content generally larger than the water content of the azeotrope) into a pervaporation membrane separator to perform primary dehydration so as to break azeotropy, feeding the solvent into a rectification tower to perform deep dehydration, returning a water-containing component at the tower top to the membrane separator and dehydrating again. An anhydrous finished product is obtained from the tower bottom. The water content of the organic solvent obtained by the processes and the method is 0.01-1 wt%. Compared with the prior art, the processes are simple, the equipment investment is low, the energy consumption is low, the product quality is high, and production of organic solvents with extremely low water contents, which is out of the reach of various kinds of rectification and other chemical manners, is achieved.

A bipolar plate for a fuel cell including pores extending between cooling fluid flow channels and reactant gas flow channels defined by the plate. Pervaporation membranes cover the pores and selectively allow water in the cooling fluid flowing down the cooling fluid flow channels to pervaporate through the membrane and humidify the reactant gas flowing down the reactant gas flow channels. In one embodiment, the bipolar plate includes two stamped unipolar plates secured together.

The invention relates to a technique for recovering tetrahydrofuran by a pervaporation method, which comprises the following steps: adding crude tetrahydrofuran into a distillation kettle, adding acid or alkali to regulate the pH value to a neutral state, adding a reducer to remove peroxides in the crude tetrahydrofuran, distilling by heating, condensing the distilled hydrous tetrahydrofuran, collecting the hydrous tetrahydrofuran in a storage tank, discharging salt, heavy organic substance and part of water from the kettle bottom, delivering the hydrous tetrahydrofuran to a preheater through a pressure pump, exchanging heat with high-purity tetrahydrofuran steam at the preheater, sending into an evaporator, and sending the hydrous tetrahydrofuran from the evaporator into a pervaporation membrane separator, wherein the infiltration side of the pervaporation membrane separator is connected with a vacuum system; condensing infiltration water by an infiltration liquid condenser, sending into an infiltration liquid tank, and obtaining high-purity tetrahydrofuran at the trapping side of the pervaporation membrane separator; and passing the high-purity tetrahydrofuran through a preheater, condensing through a finished product condenser, and sending into a product tank. The invention has the advantages of simple technical process, high safety factor, low equipment investment, high energy utilization efficiency and high recovery rate.

The invention discloses a direct methanol fuel cell capable of realizing pure methanol supply. The fuel cell comprises a cell shell, and a pervaporation membrane which is fixed on the cell shell and divides an inner chamber into a methanol fuel chamber and a steam chamber, wherein an anode flow field plate, a membrane electrode and a cathode flow field plate are sequentially arranged above the steam chamber from bottom to top in a stacking manner; a hollow cover plate covering a cathode collector plate is arranged at an open end of the cell shell in an insulation manner; a hydrophilic porous plate with hydrophily is arranged between the anode flow field plate and the anode side of the membrane electrode; a hydrophobic porous plate with hydrophobicity is arranged between the cathode side of the membrane electrode and the cathode flow field plate. According to the invention, continuous vaporization methanol supply is guaranteed, methanol crossover is restrained while cathode water is promoted to be reversely supplemented to the anode to participate in reaction, on the premise of guaranteeing output performance of the cell, the energy density of the cell is increased effectively, high-concentration methanol supply even pure methanol supply of the cell is realized and the service life of the cell is prolonged greatly.

The invention discloses a recovery method for aroma components in a production process for instant tea powder. The recovery method comprises the following steps: crushing tea into coarse powder by using a pulverizer, mixing the obtained tea powder with water and extracting aroma components in the tea; filtering tea soup obtained after extraction by using a multilayer plate and frame type filter press; subjecting a filtrate obtained after plate and frame type filtration to ultrafiltration so as to obtain a clear filtrate and subjecting the filtrate to vacuum concentration; subjecting a concentrate obtained after concentration to spray drying so as to obtain the tea powder, wherein solid content of the concentrate is 40 to 50 wt%; and with condensed water generated in the process of vacuum concentration as a material liquid for pervaporation, carrying out pervaporation membrane separation and subjecting concentrated aromatic substances in the tea to spray drying to recover the aromatic substances to the tea powder. According to invention, most aromatic substances in the tea can be recovered, the quality of the tea powder is improved, and the utilization rate of the tea is increased; compared with a traditional extractive distillation method and the like, the recovery method for the aroma components in the tea through pervaporation membrane separation has the advantages of high separability, low energy consumption, a mild operation temperature, no additive, etc.

The invention relates to a method for preparing a composite pervaporation membrane. The method comprises the following steps of: dissolving an organic matter in a solvent to prepare a homogeneous phase membrane forming solution; adding a crosslinking agent and a difunctional conditioning agent into the membrane forming solution, uniformly mixing and adding a catalyst; coating the prepared membrane forming solution containing the difunctional conditioning agent on a supporting body; and finally performing aftertreatment on the composite membrane to prepare the composite pervaporation membrane.By the method, the permeability and selectivity of the pervaporation membrane can be improved simultaneously, and the stability of the composite membrane is also improved.

The invention discloses a method for continuously producing biological butanol by fermentation, separation and coupling of a static bed. The method comprises the following steps of: filling a modified immobilized medium into the static bed, and circularly connecting in series with a bioreactor; incubating a butanol producing strain into the bioreactor, culturing the butanol producing strain in a fermentation medium, circulating fermentation liquor between the static bed and the bioreactor, and gradually absorbing free thallus cells into the static bed; pumping the fermentation liquor into a pervaporation membrane module for separation when the concentration of the butanol in the bioreactor is between 3 and 7g/L, collecting penetrating fluid, and returning liquid intercepted by a membrane to the bioreactor for continuous use; meanwhile, adding the fermentation medium into the midstream of the bioreactor, and continuously fermenting to produce the butanol. The method obviously weakens the pollution of the pervaporation membrane existing in the process of in situ separation and coupling, prolongs the operation time and service life of the membrane, eliminates butanol product inhibition in a fermentation process, and realizes the high-efficient and continuous production of the biological butanol.

The invention discloses a preparation method of an ethanol-permselective POSS (polyhedral oligomeric silsesquioxanes)/silicone rubber composite membrane and belongs to the technical field of pervaporation membrane separation. A membrane liquid formed by mixing of silicone rubber, POSS, a cross-linking agent, a catalyst and a solvent is prepared; a porous support PVDF (polyvinylidene fluoride) base membrane is coated with the membrane liquid; and the POSS/silicone rubber composite membrane is obtained through deep cross-linking. The obtained POSS/silicone rubber composite membrane has excellent ethanol-permselective performance for ethanol aqueous solutions with low concentration (1wt%-30wt%), and the separation factor alpha obtained is 1.70 and the permeation flux J is 0.15 kg/m2h under the optimum condition for ethanol aqueous solutions with the concentration of 10wt%.

The invention relates to a method and a device for producing biomass absolute ethyl alcohol, and belongs to the technical field of organic solvent dehydration. The equipment used by the production method comprises a pressurized rectifying tower, an atmospheric rectifying tower, a vacuum distillation tower and a pervaporation membrane dehydration device, wherein the equipment is connected through a pipeline and a valve; reboiling heat at the bottom of the pressurized rectifying tower is provided by primary steam; the reboiling heat at the bottom of the atmospheric rectifying tower is provided by an overhead product of a high-pressure tower; and the reboiling heat at the bottom of the vacuum distillation tower is provided by the overhead product of an atmospheric tower. A feed solution enters the rectifying tower after being preheated by an absolute ethyl alcohol product and kettle raffinate; and the overhead product of the rectifying tower is further evaporated after being mixed, and then enters the pervaporation membrane dehydration device to dehydrate. According to the production method, optimal configuration of all levels of energy in the system is considered, thus the target of the system for saving energy is achieved, and the steam consumption of the overall system can be saved by over 30%-50% in comparison with a traditional technology.

The present invention provides proton exchange membrane of fuel battery with anti gas permeation layer and humidifying function and producing method thereof. The proton exchange membrane is combined by a H2, O2 anti gas permeation membrane or layer in the middle of proton exchange membrane of porous polymer base, the anti permeation membrane or layer comprises of porous proton exchange membrane base and filler, wherein, the filler is catalyzer or inorganic nano granules or/and proton exchange resin. The producing method is: dispersing filler in solution to gain catalyzer slurry; dipping porous proton exchange membrane in catalyzer slurry to form porous proton exchange membrane of filler catalyzer; hot pressing to form gas permeation membrane or layer, and piled up from up to down with porous polymer basic proton exchange membrane in the turn of porous polymer basic proton exchange membrane- anti gas permeation membrane- porous polymer basic proton exchange membrane, on bottom and top of which polytetrafluoroethylene films with identical dimension are set on, after hot pressing, tearing off the polytetrafluoroethylene film to gain the products.

The invention provides a thin layer composite positive osmosis membrane and a preparation method of the thin layer composite positive osmosis membrane, aiming at effectively reducing concentration polarization in positive osmosis and greatly improving the water flux. The invention provides a thin layer composite positive osmosis membrane containing an ultrathin support layer, and a preparation method of the thin layer composite positive osmosis membrane, so that the defects of the prior art are made up. The ultrathin support layer of the thin layer composite positive osmosis membrane is a self-support carbon nano tube support layer or a hydrophilic modification carbon nano tube support layer; a skin layer of the thin layer composite positive osmosis membrane is a polyamide layer compounded on the surface of the self-support carbon nano tube layer. Due to the good support layer structure of the self-support carbon nano tube layer, a brand new thin layer composite positive osmosis membrane concept is provided, so that a new way of a high-performance positive osmosis membrane is opened up at home and abroad. Furthermore, the operation of interfacial polymerization is completed on the surface of the self-support carbon nano tube layer, the positive osmosis membrane with remarkably improved performances can be obtained, and a new thought is provided for the preparation of other novel materials.

The invention discloses a preparation method for an interpenetrating network dealcoholization pervaporation membrane, which includes the following steps: 1) preparing membrane producing materials: mixing well an inorganic additive, an evocating agent, a solution and a component I and a component II constituting the interpenetrating network to form the membrane producing materials; 2) the interpenetrating network is formed through cross bonding: adding catalyst in the membrane producing materials and mixing at a temperature ranging from 20 DEG C to 30 DEG C for 10 to 20 hours, and then adding a cross linker to mix and perform cross linking reaction at a temperature ranging from 50 DEG C to 70 DEG C for 2 to 6 hours, thus acquiring a casting solution; 3) membrane casting and post treatment: carrying out membrane casting and post treatment of the casting solution, thus acquiring the interpenetrating network dealcoholization pervaporation membrane. The interpenetrating network dealcoholization pervaporation membrane with hydrophobic nature prepared by the method of the invention is characterized by strong swelling resistance ability, high separation factor and so on.

The invention provides a nano-fiber-based composite pervaporation membrane and a preparation method thereof. The nano-fiber-based composite pervaporation membrane is characterized by including a basic layer, a middle transitional layer and a surface layer, wherein the basic layer is a nano-fiber porous support layer, the middle transitional layer is a modified oxidized graphene layer, and the surface layer is a separation layer having interfacial polymerization activity. The simple, modified, thickness-controllable, flexible and ultrathin oxidized graphene skin layer serves as the middle transitional layer, the thickness and uniformity of a function barrier layer on the surface of the composite membrane and the interface acting force of a compact separation layer and the middle transitional layer can be rapidly and accurately adjusted and controlled by controlling interfacial polymerization and optimization, and accordingly the pervaporation performance of the composite membrane is enhanced.

The invention discloses a forward osmosis membrane based on interface hydrophilic modification. The forward osmosis membrane comprises a separation peel layer arranged on the surface, a porous support layer arranged in the middle and a non-woven fabric support material arranged at the lower part. The forward osmosis membrane is characterized in that a hydrophilic polymer layer is also arranged between the porous support layer and the non-woven fabric support material, and is embedded into the non-woven fabric support material; the non-woven fabric support material is made of polyolefin or polyester. The hydrophilic polymer can also be interlinked through a crosslinking agent. The forward osmosis membrane has the advantages that through the hydrophilic modification, on the one hand, the permeation resistance of water in a permeation process is reduced, and the water flux is improved, and on the other hand, in a phase inversion process, the water can easily permeate, so that an instant phase inversion can be more easily generated; a large pore structure is formed; the porosity is improved; the sinuosity of pores is reduced, so that the inner concentration polarization can be obviously reduced; the water flux of the membrane is improved.

A process for improving the quality of novel alcohol by permeation, evaporation, separation and reforming relates to application of separation technique with pervaporation membrane in the field of alcohol. The technique of the invention is that raw material alcohol is maintained in constant relatively low temperature, the liquor is transferred to a silastic composite membrane device by a pump and the liquor conducts circular flow in the upper reaches of the membrane, the lower reaches of the membrane is maintained in vacuum state by a vacuum pump, ethanol and volatile flavoring substances are selectively separated by pervaporation and turn into permeation vapor, representative mouth feeling and flavoring substances are reformed or concentrated in vapor, a low temperature condenser is equipped in the lower reaches of the membrane, condensed liquor with different components quantity of mouth feeling and flavoring substances is achieved by time steps of condensing of the permeation vapor, the liquor made by time steps of condensing is reformed and novel alcohol with high quality is blended. The process has the advantages of simple technological process, compact equipment, high maneuverability, short treatment period, which can develop novel alcohol with low cost and poor quality into novel alcohol with high price and good quality.