32 results about "Modified ultrafiltration" patented technology

The invention discloses a hydrophilic polyethersulfone ultrafiltration membrane based on metalloporphyrin coordination modification as well as a preparation method and application of the hydrophilic polyethersulfone ultrafiltration membrane. According to the ultrafiltration membrane, a membrane casting solution is prepared by blending a polyether sulfone base material, an organic solvent, a pore-foaming agent and tetra (4-aminophenyl) porphyrin, and the membrane casting solution is cured and formed in a coagulating bath containing ferric ions through a phase inversion process. The preparation method is characterized in that porphyrin compounds and iron ions are subjected to an in-situ coordination reaction in the phase inversion process to form a stable metalloporphyrin complex network structure, and the prepared ultrafiltration membrane has the following advantages that the hydrophilicity is increased, and the pure water flux is increased; the protein rejection rate is not less than 95%; the antibacterial property and the anti-pollution property are excellent. The process is simple and controllable, and the obtained membrane material has important application value in the field of biological medicine separation.

The present invention provides a magnetic quaternized ZIFs nanoparticle and a modified ultrafiltration membrane thereof, belonging to the technical field of ultrafiltration membrane preparation. The preparation method of the ZIFs nanoparticles comprises the following steps: quaternizing an imidazole compound to obtain a quaternized imidazole compound; mixing the quaternized imidazole compound with an imidazole compound, magnetic particles, and solvent 1 to obtain solution 1; mixing a zinc salt with solvent 1 to obtain solution 2; and adding solution 2 dropwise to solution 1 to react and obtain ZIFs nanoparticles. The present invention first prepares ZIFs nanoparticles, and then prepares an ultrafiltration membrane using the nanoparticles under the action of a magnetic field. The magnetic field force can change the distribution of the casting solution containing the magnetic particles, while increasing the distribution density of the filler in the cortex and effectively improving the utilization rate of the filler, thereby improving the microstructure and performance of the membrane, so that the membrane has high pure water flux and flux recovery rate, and has good antibacterial properties.

The invention discloses a graphene oxide-reduced graphene oxide synergistic modified polyvinylidene fluoride ultrafiltration membrane as well as a preparation method and application thereof. The ultra-filtration membrane is prepared by a non-solvent induced phase separation method, and is characterized in that graphene oxide and reduced graphene oxide are synchronously added into a polyvinylidene fluoride membrane casting solution, and a composite lamellar structure with a hydrophilic-hydrophobic interpenetrating and embedding synergistic effect is constructed in a membrane forming process by utilizing the differences of the graphene oxide and the reduced graphene oxide in hydrophilicity, dispersity and chemical properties. The graphene oxide endows the membrane with lasting hydrophilicity and water transmission channels, and the reduced graphene oxide provides excellent antibacterial property, oxidation resistance, mechanical enhancement effect and resistance to strong solvents, salts, acids, alkalis, aromatic hydrocarbons, halogens and other media through closer stacking. According to the synergistic modified ultrafiltration membrane, the water flux and the interception performance are remarkably improved, meanwhile, the mechanical strength, the organic pollution resistance and the biological pollution resistance of the membrane are enhanced, and the synergistic modified ultrafiltration membrane is particularly suitable for efficient separation and purification of various complex and difficult-to-purify sewage such as oil-containing wastewater, pharmaceutical wastewater, chemical wastewater, biological wastewater and harsh wastewater.

The application discloses a preparation method and application of a polyacid tannic acid modified ultrafiltration membrane, and the preparation method comprises the following steps: preparing a casting solution containing a high molecular film forming material and a solvent; adding a polyoxometalate into the casting solution, uniformly mixing, and obtaining a polyacid modified casting solution; scraping and coating the polyacid modified casting solution to form a liquid membrane, pre-evaporating, immersing into a coagulation bath containing tannic acid to perform phase inversion and film forming, and obtaining the polyacid tannic acid modified ultrafiltration membrane. Through the synergistic effect of the polyacid blending regulation of the membrane pore structure and the in-situ coordination modification of the tannic acid phase separation, the simultaneous improvement of the permeation flux and the retention rate is realized, the pure water flux of the obtained ultrafiltration membrane reaches 221.37 LMH, the bovine serum albumin retention rate reaches 96.17%, and the preparation process is simple, efficient, and has a good large-scale application prospect.

The application relates to a preparation method of a modified ultrafiltration membrane for high-efficiency separation of nanoplastics in water bodies, and belongs to the field of environmental engineering water treatment. The application provides a preparation method of a modified ultrafiltration membrane for high-efficiency separation of nanoplastics in water bodies, which is prepared by impregnation modification of the ultrafiltration membrane by tea polyphenol and 3-aminopropyl triethoxysilane, realizes high hydrophilicity of the membrane surface and high separation efficiency of nanoplastics in water bodies. The application provides a polyvinylidene fluoride ultrafiltration membrane modification method based on synergistic modification, the hydrophilicity and anti-pollution performance of the membrane surface are obviously improved by optimizing the modification process, the nanoplastics exhibit excellent removal efficiency, and the removal rate is more than 99%; meanwhile, the stability of the modified layer is improved through a chemical crosslinking mechanism, the service life of the membrane is effectively prolonged, the limitations of insufficient separation precision and hydrophobicity of the membrane surface in the prior art are overcome, and an innovative solution is provided for high-efficiency separation of nanoplastics in water bodies.

This invention discloses a layer-by-layer deposition modified ultrafiltration membrane with both antifouling and antibacterial properties, its preparation method, and its applications. Through layer-by-layer assembly technology, a tannic acid (TA) anion layer and a polyhexamethylene biguanide (PHMB) cation layer are alternately deposited on the surface of an ultrafiltration membrane. Under weakly alkaline conditions, electrostatic interactions, hydrogen bonding, Schiff base reactions, and Michael addition reactions are simultaneously utilized to achieve both non-covalent and covalent bonding, constructing a stable and dense integrated antibacterial-antifouling composite coating. This coating has a contact-type antibacterial structure, which can effectively kill bacteria in water and inhibit biofilm formation at the source. Simultaneously, it significantly improves the hydrophilicity of the membrane surface, reduces pollutant adsorption and deposition, and achieves synergistic enhancement of antibacterial and antifouling properties. The preparation process of this invention is mild, simple, low-cost, and environmentally friendly. The modified membrane exhibits high flux retention, excellent separation performance, and excellent operational stability, and can be widely applied in water treatment scenarios such as municipal wastewater treatment.

The invention discloses a preparation method of bovine spinal cord peptide, belongs to the technical field of biology, and is used for solving the technical problems that in the prior art, degreasing agents such as petroleum ether are weak in polar lipid dissolving capacity, and enzymatic hydrolysate is separated by adopting a conventional nanofiltration membrane, so that the manufacturing cost is high, and the service life is short. The preparation method of the bovine spinal cord peptide comprises the following steps: S1, cleaning fresh bovine spinal cords, crushing the cleaned bovine spinal cords into blocks, and pulping the blocks to obtain homogenate tissues; adding a degreasing agent into the homogenized tissue, and performing ultrasonic treatment to obtain degreased spinal cord; s2, adding compound enzyme into the degreased spinal cord for reaction to obtain enzymatic hydrolysate; carrying out enzyme deactivation on the enzymatic hydrolysate in boiling water to prepare a bovine spinal cord crude peptide solution; s3, centrifuging the bovine spinal cord crude peptide solution, and collecting supernate; and passing the supernate through a modified ultrafiltration membrane, and circularly performing ultrafiltration for multiple times to prepare the bovine spinal cord peptide. According to the method, the homogenate tissue is deeply degreased by designing the composite degreasing agent with a surfactant-like structure; and the modified ultrafiltration membrane is used for improving the purity of the filtered bovine spinal cord peptide.

This invention discloses a PVDF-modified ultrafiltration membrane based on a tannic acid crosslinking network, its preparation method, and its applications. The membrane is prepared by a phase inversion membrane fabrication method using polyethyleneimine, tannic acid, polyvinylidene fluoride (PVDF), and N,N-dimethylacetamide (NDM). The pyrogallol structure abundant in the tannic acid molecule can coordinate with metal ions and also form a robust covalent crosslinking network with the amine-rich polyethyleneimine through Michael addition and Schiff base reactions. This network firmly anchors TA to the membrane surface and pores, solving the problem of TA loss in traditional modifications. The introduction of TA imparts lasting hydrophilicity to the membrane, significantly improving pure water flux and separation efficiency. Simultaneously, the hydrophilic and positively charged surface synergistically constructed by TA and PEI effectively inhibits the adsorption and deposition of pollutants, endowing the membrane with excellent antifouling performance and operational stability. This PVDF membrane, prepared through a green and simple co-crosslinking strategy, shows broad application prospects in complex water treatment and bioseparation.

The invention provides an ultrafiltration membrane hydrophilic treatment method which comprises the following steps: S1, soaking an ultrafiltration membrane in an organic solvent for full wetting to obtain a wetted ultrafiltration membrane; s2, putting the wetted ultrafiltration membrane into a microcapsule emulsion, and carrying out first soaking treatment to obtain a first soaked ultrafiltration membrane; s3, placing the ultrafiltration membrane after the first soaking in an organic weak acid solution for second soaking treatment to obtain a hydrophilic modified ultrafiltration membrane; wherein the microcapsule emulsion is formed by dispersing a microcapsule into water, the microcapsule has a core-shell structure, the core-shell structure comprises a microcapsule core and a microcapsule shell, the microcapsule core is inorganic nanoparticles, and the microcapsule shell is chitosan. The method is mild in reaction condition, simple in operation step and easy to realize industrialization.

The invention discloses a reverse osmosis membrane based on a perfluorosilane modified ultrafiltration membrane as well as a preparation method and application of the reverse osmosis membrane. The preparation method comprises the following steps: firstly, blending perfluorosilane and a membrane casting solution, and preparing the perfluorosilane modified ultrafiltration membrane by a phase inversion method; the ultrafiltration membrane is used as a supporting layer, and the surface of the ultrafiltration membrane is respectively impregnated with a water phase solution containing polyamine and an organic phase solution containing polyacyl chloride to prepare a polyamide separation layer. According to the method, perfluorosilane is introduced into the supporting layer through blending modification, the surface pore characteristics and physicochemical properties of the supporting layer are optimized, the interfacial polymerization process is effectively regulated and controlled, the surface of the separation layer is rougher, and therefore the effective water permeable area of the separation layer is increased. Meanwhile, a C-F long chain of the perfluorosilane endows pores in the supporting layer with strong hydrophobicity and low surface energy characteristics, and the transmission resistance of water molecules in the supporting layer is remarkably reduced. The separation layer and the supporting layer of the reverse osmosis membrane are synchronously optimized through the modified ultrafiltration membrane, and the water permeability of the reverse osmosis membrane is remarkably improved on the premise that the salt rejection rate is not sacrificed.

The invention discloses a modified ultrafiltration membrane, a preparation method thereof and a method for preparing a protein sample for mass spectrometry by adopting the modified ultrafiltration membrane, and belongs to the technical field of protein sample preparation. The surface of the ultrafiltration membrane is subjected to graft modification, so that the hydrophilicity of the surface of the membrane is effectively enhanced, that is, protein adsorption and membrane pollution are reduced by reducing the hydrophobicity of the surface of the membrane and increasing the hydrophilicity. According to the invention, amphoteric small molecules are connected to cellulose molecules of the ultrafiltration membrane, so that hydrophilic ends face outwards to mutually form hydrogen bonds to improve the hydrophilicity. Specifically, according to the method, the membrane is firstly subjected to alkaline activation, then amphoteric small molecules are inoculated, and the connection efficiency is improved. When the modified material is used for preparing a protein sample, the adsorption effect of the membrane on the protein sample can be reduced, the number of identified proteins and peptide fragments is finally increased, protein loss is reduced in the sample pretreatment step, and identification of more proteins and peptide fragments is facilitated.

The invention relates to the technical field of saccharin sodium waste treatment, and particularly discloses a treatment process of saccharin sodium waste. The treatment process of the saccharin sodium waste comprises the following steps: S1, precipitating; s2, carrying out secondary filtration; s3, purifying; s4, carrying out biodegradation; s5, catalytic treatment; s6, disinfection; wherein in the secondary filtration treatment, an ultrafiltration membrane is used for filtration, and the ultrafiltration membrane is a biochar modified ultrafiltration membrane. According to the preparation process disclosed by the invention, inorganic matters such as Cu < 2 + > in the wastewater are fully treated in a secondary filtering manner, so that the treatment effect on the saccharin sodium waste is improved.

The invention discloses improved ultrafiltration heat preservation equipment, and relates to the technical field of medical instruments. The improved ultrafiltration heat preservation equipment comprises an ultrafiltration pipeline, an ultrafilter and a temperature control device, the ultrafiltration pipeline comprises an infusion catheter and a liquid outlet catheter; the liquid inlet end of the ultrafilter is communicated with the infusion catheter, the liquid outlet end of the ultrafilter is communicated with the liquid outlet catheter, the infusion catheter is suitable for inputting blood into the ultrafilter, and the liquid outlet catheter is suitable for outputting the blood filtered by the ultrafilter; the temperature control device is communicated with the liquid outlet catheter and used for adjusting the blood temperature. The structure of the improved ultrafiltration heat preservation equipment is improved, the temperature control device is used for controlling the blood temperature, the blood temperature can be kept within the normal range, arrhythmia and endangering the life of a child patient due to the fact that the body temperature of the neonate is rapidly decreased after improved ultrafiltration are avoided, the safety of improved ultrafiltration is greatly improved, meanwhile, operation is simplified, and the cost is reduced. And medical personnel do not need to adopt other operations to increase the body temperature of the child patient.

The invention discloses a self-cleaning filtering method for water treatment, and belongs to the technical field of fountain water treatment. Comprising pretreatment, filtration and adsorption treatment and disinfection treatment. The pretreatment stage comprises the following steps: centrifugally separating the spring, adding a composite functional agent containing modified polyaspartic acid, modified glucosamine hydrochloride and the like, and filtering through a microfiltration screen; in the filtering adsorption treatment stage, the pretreated effluent is mixed with a modified silicon dioxide-polyepoxysuccinic acid compound self-cleaning agent and then introduced into a PVDF-TiO2 composite modified ultrafiltration membrane assembly, and membrane effluent is treated through an nHAP-activated carbon composite adsorption column; in the disinfection treatment stage, food-grade sodium hypochlorite is added into the deeply-treated water for disinfection, and the disinfected water is treated through an activated carbon adsorption tank to obtain the treated bubbling spring. The problems that a high-turbidity and high-calcium scale composite layer is difficult to remove, a humic acid-calcium complex is difficult to adsorb, and high-drug-resistance bacteria are difficult to disinfect in the karst rainy season can be solved.

The invention belongs to the technical field of ocean wastewater treatment and resource recovery, and particularly discloses an integrated membrane treatment device and method for oil removal and lithium extraction of ocean platform production water.The device body comprises a first-stage oil removal unit and a second-stage lithium extraction unit which are sequentially connected, the first-stage oil removal unit adopts a hydrophilic modified ultrafiltration membrane or microfiltration membrane, and the second-stage lithium extraction unit adopts a hydrophilic modified ultrafiltration membrane or microfiltration membrane; the oil content of inlet water is reduced to below 10mg / L through cross-flow filtration; the secondary lithium extraction unit adopts a composite adsorption film loaded with a lithium ion sieve, selective lithium extraction is carried out on deoiled water, meanwhile, the device is integrated with a monitoring control system and a cleaning regeneration system, and a modular skid-mounted design is adopted. Through cooperation of two stages of functional membranes, deep oil removal and efficient lithium extraction are synchronously completed in a single compact system, the problems that an adsorption method is poor in oil stain resistance and process equipment is dispersed are solved, and the device has the advantages of being high in anti-pollution capacity, high in resource recovery rate, high in automation degree and suitable for offshore platform space limitation.

A negatively charged carboxylated carbon nanotube-modified ultrafiltration membrane: Carboxylated carbon nanotubes are placed in an aqueous solution of FeCl3·6H2O and stirred until homogeneous to obtain a mixed solution of carboxylated carbon nanotubes and hydrated iron oxide; KOH solution is added to the mixed solution of carboxylated carbon nanotubes and hydrated iron oxide, the pH is increased to 7, and then treated in a water bath. The precipitate is washed until neutral and no chloride ions are detected; after aspiration filtration, the precipitate is dried to obtain carboxylated carbon nanotube particles loaded with HFO; the HFO-loaded carboxylated carbon nanotube particles are dispersed in a diluent and ultrasonically treated; polymer particles and a pore-forming agent are added to the diluent sequentially, and the mixture is ultrasonically mixed and stirred until homogeneous. After standing to degas and cool, a casting solution is obtained; the casting solution is scraped onto a glass plate and placed in pure water to undergo non-solvent-induced phase separation. After phase inversion, a negatively charged carboxylated carbon nanotube-modified ultrafiltration membrane is obtained. This invention also provides a preparation method and applications.

The application discloses a preparation method of a high-efficiency positive-charged nanofiltration membrane for separating metal ions. The method is characterized in that a polysulfone ultrafiltration membrane base film is modified by graphene and SiO2, and then polyethylene imine (PEI) modified by polyglycidylamine (PGAM) is grafted on the modified ultrafiltration membrane to successfully prepare the positive-charged nanofiltration membrane. The nanofiltration membrane combines the high strength and hydrophilic advantages of graphene and SiO2, and is endowed with positive charges on the membrane surface through the modification of polyethylene imine and polyglycidylamine. The prepared positive-charged nanofiltration membrane significantly improves the separation efficiency and durability of metal ions, and has significant application value and broad prospects in key fields such as seawater desalination, wastewater treatment and resource recovery.

The application discloses a kind of self-cleaning filtration methods for water treatment, belong to gushing spring water treatment technical field;Including pretreatment, filtration adsorption treatment and disinfection treatment;Pretreatment stage, after centrifugal separation, gushing is added with the composite functional agent containing modified polyaspartic acid, modified glucosamine hydrochloride etc., and is filtered by microfiltration screen;Filtering adsorption treatment stage, after mixing pretreatment effluent with modified silicon dioxide-polyepoxysuccinic acid compound self-cleaning agent, into PVDF-TiO2 Compound modified ultrafiltration membrane module, membrane effluent is treated by nHAP-activated carbon composite adsorption column;Disinfection treatment stage, food-grade sodium hypochlorite is added to the advanced treatment water, and after disinfection, active carbon adsorption tank is handled to obtain treated gushing spring.The application can solve the problem that high turbidity and high calcium scale composite layer of karst rainy season gushing spring is difficult to remove, humic acid-calcium complex is difficult to adsorb, and high drug-resistant bacteria is difficult to disinfect.

The application discloses a bacteria liquid separation method for preparing acrylamide based on a microbial method, and relates to the technical field of acrylamide synthesis. The bacteria liquid separation method comprises the following steps: depositing a hydrophilic modifier on the surface of an ultrafiltration membrane to obtain a modified ultrafiltration membrane; adding an adsorbent to acrylamide hydrate liquid, stirring, forming agglomerates in the acrylamide hydrate liquid, removing the agglomerates through filtration to obtain pretreated liquid; filtering the pretreated liquid through the modified ultrafiltration membrane, recovering the filtered bacteria, and then sequentially performing continuous ion exchange and concentration to obtain acrylamide liquid finished product. The method disclosed by the application is helpful to reducing membrane pollution of the ultrafiltration membrane and improving the separation effect of the ultrafiltration membrane on the bacteria liquid by pre-hydrophilic modification treatment of the ultrafiltration membrane and pre-adsorption treatment of the acrylamide hydrate liquid.

The invention provides a ginseng-radix astragali extract essence plant beverage composition containing ginseng and radix astragali and a preparation method thereof, and belongs to the technical field of plant beverages. The composition takes an extract obtained by performing similar wild ginseng treatment on artificially planted ginseng as a core, and is matched with compound herbal raw materials such as astragalus membranaceus and angelica sinensis and functional auxiliary materials, the composition is prepared from the following raw materials in parts by weight: 0.8-1.5 parts of similar wild ginseng extract, 3-6 parts of astragalus membranaceus and the like, ginsenoside Rb1 in a finished product is more than or equal to 4.0 mg / g, Rg3 in the finished product is more than or equal to 4.5 mg / g, specific active peptide is contained, astragalus polysaccharide is more than or equal to 1.2 mg / mL, and the content of the active peptide is more than or equal to 1.0 mg / mL. The small molecule active component accounts for not less than 85%, and the solubility is not less than 98%. The core of the preparation method comprises the following steps: carrying out compound strain fermentation on artificially planted ginseng, carrying out compound enzymolysis, carrying out modified ultrafiltration membrane purification similar wild ginseng treatment, carrying out compound herbal synergistic extraction, mixing and blending, and carrying out instantaneous sterilization and filling. The invention solves the problems of low content of effective components, poor absorptivity and insufficient functionality of the traditional ginseng and astragalus drink.

The invention provides a membrane recovery method of a heavy metal catalyst in medicine wastewater. Relates to the technical field of environmental engineering and membrane separation, and comprises the following steps: S1, adding a biodegradable chelating agent into the pharmaceutical wastewater, so that an ionic heavy metal catalyst is complexed and fused with an original micro-colloid to form a catalyst micelle; s2, enabling the wastewater treated in the step S1 to pass through a hydrophilic-oleophylic synergistically modified ultrafiltration membrane assembly in a shear cross-flow manner, and intercepting the catalyst micelles to obtain a pre-concentrated solution. The membrane recovery method of the heavy metal catalyst for the pharmaceutical wastewater meets the industrial application requirements of low energy consumption, low maintenance cost and long-period stable operation, and the economical efficiency and sustainability of a membrane separation recovery process are remarkably improved.

The application relates to a novel modified ultrafiltration membrane and a preparation method, and relates to the technical field of wastewater treatment. The novel modified ultrafiltration membrane comprises the following steps: preparing a reduced graphene oxide solution; obtaining silicon carbide, and preparing beta silicon carbide by using the silicon carbide and silicon dioxide; and obtaining the reduced graphene oxide solution, the beta silicon carbide and polysulfone membrane filaments to prepare the novel modified ultrafiltration membrane. The novel modified ultrafiltration membrane fully combines the characteristics of the graphene oxide and the beta silicon carbide to realize efficient treatment of wastewater.

The present invention discloses an iron-based MOF material modified ultrafiltration membrane, a preparation method thereof, and an application thereof. The preparation method of the iron-based MOF material modified ultrafiltration membrane comprises the following steps: S1, in the presence of a solvent, crystallizing a mixture of iron salt and 2-aminoterephthalic acid to obtain an iron-based MOF material; wherein the mass ratio of 2-aminoterephthalic acid to iron salt is 3:(3-13); S2, sequentially adding an acrylic monomer and a PVDF membrane to the mixture containing the iron-based MOF material, ultrasonically mixing, and irradiating the mixture to obtain the obtained membrane. The iron-based MOF material modified ultrafiltration membrane of the present invention has excellent flux, pH responsiveness, and anti-pollution properties, and can effectively intercept Ce. 3+ This solves the problem that radioactive wastewater has less complex sites under the conditions of pH and ion concentration, which leads to the ultrafiltration membrane being sensitive to Ce. 3+ It solves the problem of reduced retention rate and shows good filtration performance in the treatment of radioactive wastewater.

The invention belongs to the technical field of ultrafiltration membranes, and particularly relates to a modified polyvinylidene fluoride ultrafiltration membrane and a preparation method thereof. The method comprises the following steps: firstly, carrying out alkali activation treatment on PVDF (Polyvinylidene Fluoride), and then carrying out graft copolymerization reaction on the PVDF, vinyl methyl oxazolidinone and a zwitterionic monomer SBVI (Styrene-Butadiene-Vinyl Vinyl Chloride), so as to prepare a graft copolymer PVDF-g-P (VMOX-co-SBVI); and then blending with a PVDF (Polyvinylidene Fluoride) matrix to prepare a membrane casting solution, and carrying out blade coating, phase inversion and drying to obtain the modified ultrafiltration membrane. VMOX provides strong hydrophilicity and is beneficial to formation of a hydration layer and improvement of processing performance; the SBVI has the hydrophilic anti-pollution property of the sulphobetaine and the antibacterial function of the imidazole group at the same time. The two components have a synergistic effect, have good compatibility with PVDF, and can form a stable interpenetrating network in the membrane, so that dual prevention and control of pollutants are realized, and the mechanical property of the membrane is remarkably improved. By adjusting the blending ratio, the hydrophilicity, antibacterial property and mechanical strength of the membrane can be flexibly regulated and controlled, so as to meet different water treatment application requirements.

The invention relates to a preparation method for treating isosorbide dimethyl ether by adopting a membrane, and belongs to the technical field of organic synthesis. Adding isosorbide and a catalyst into a reaction kettle, and uniformly stirring and mixing to obtain a mixed material; uniformly mixing sodium methoxide and methanol to obtain a sodium methoxide-methanol solution; heating the mixed material, synchronously adding a sodium methoxide-methanol solution and distilled water, and carrying out an etherification reaction to obtain a mixed solution; the catalyst can be recovered in a magnetic separation manner in the reaction process; slowly dropwise adding hydrochloric acid into the mixed solution until the pH value is neutral, and then carrying out constant-temperature distillation to obtain a fraction solution; and carrying out reduced pressure distillation on the fraction liquid to remove residual methanol, and filtering through a modified ultrafiltration membrane to obtain the isosorbide dimethyl ether, the modified ultrafiltration membrane is modified through sorbic acid steam, argon, glutathione, papain, sodium bicarbonate and ethyl alcohol; the isosorbide dimethyl ether prepared by the method disclosed by the invention has relatively high purity and yield.

The application discloses a gradient pressurized concentration preparation method of an oligonucleotide high-concentration API solution and belongs to the technical field of medicines. The application first proposes a gradient pressurized-temperature control cooperative concentration process, introduces a pre-treatment step of osmotic pressure regulation, solves the problems of serious membrane pollution and low limit concentration in traditional constant pressure concentration, and can stably realize high-concentration concentration of 200-280 mg / mL. An amphoteric ion modified ultrafiltration membrane is adopted, online concentration monitoring and segmented temperature control transformation are carried out on traditional nanofiltration equipment, the anti-pollution ability of the membrane is obviously improved, the degree of automation of the concentration process is higher, and a reliable process scheme is provided for industrialized production of high-concentration oligonucleotide pharmaceutical preparations.

The invention discloses a preparation method of a hydrophilic polyvinylidene fluoride ultrafiltration membrane. The preparation method comprises the following specific steps: (1) adding graphene oxide, DMAc, PVP, LiCl and PVDF powder into a mixed membrane casting solution system, wherein PVDF accounts for 16-20% of the total mass of the total system; (2) placing in an oil bath at the temperature of 50-80 DEG C, and magnetically stirring for 12-18 hours to obtain a membrane casting solution; (3) putting the casting membrane solution obtained in the step (2) into a vacuum drying oven at the temperature of 50-70 DEG C, standing and defoaming for 12-24 hours to obtain a defoamed casting membrane solution; and (4) preparing the modified ultrafiltration membrane by an immersion precipitation phase inversion method. The preparation method is simple, and the obtained PVDF membrane is good in hydrophilicity, high in flux and high in pollution resistance.

The invention discloses a modified ultrafiltration membrane and a preparation method of a dietary fiber coffee solid beverage, belongs to the technical field of food processing, and provides a modified ultrafiltration membrane dopamine and branched polysulfobetaine co-deposition ultrafiltration membrane and a preparation method of a dietary fiber coffee solid beverage. Comprising coffee beans obtained by wet processing of fresh coffee fruits and soluble dietary fibers extracted from coffee pericarp. The soluble dietary fiber oligosaccharide is obtained by separating the soluble dietary fiber obtained after enzymolysis of the coffee pericarp through the modified ultrafiltration membrane, and high-valued application of the coffee pericarp which is a coffee byproduct is achieved.

The invention belongs to the technical field of water treatment, and provides a preparation method of a self-assembled modified ultrafiltration membrane for efficient separation of phosphate and sodium chloride, and the preparation method comprises the following steps: soaking the surface of an ultrafiltration membrane base membrane with an isopropanol solution, and then washing; coating the surface of the prepared membrane with a PDADMAC self-assembly solution containing NaCl, pouring out the solution after reaction, cleaning and drying the membrane; and coating the surface of the prepared membrane with a NaCl-containing PSS self-assembled solution, pouring out the solution after reaction, cleaning the membrane, and drying the membrane to obtain the self-assembled modified ultrafiltration membrane. The prepared self-assembled modified ultrafiltration membrane is low in sodium chloride retention rate, large in water flux and high in phosphate retention rate, can separate high-salt pickling wastewater to obtain sodium chloride wastewater and phosphate, and is convenient for efficiently and respectively recovering sodium chloride and phosphate.