39results about How to "Improve selective separation performance" patented technology

The invention discloses a method for separating ginkgolide B from a ginkgolide mixture. The method comprises the following steps: by using an ionic liquid or a binary mixed solvent composed of ionic liquid and water as the extracting agent, and efficiently separating ginkgolide B from a mixture, which contains ginkgolide A, ginkgolide B, ginkgolide C and other ginkgolide homologues, through a fractional extraction process. The method has the advantages that the method has high separation efficiency, low solvent consumption, high safety, environmental protection and the like and is suitable for industrial production, etc.

The invention provides a PEBA (Polyether block amide) composite film as well as a preparation method and application thereof. The PEBA composite film comprises a base film, a PEBA separation layer and a transition layer, wherein the transition layer is used for connecting the base film and the PEBA separation layer, and comprises hydrophilic silicone oil. The invention further discloses the preparation method for the PEBA composite film. The method comprises the step of sequentially coating a transition layer solution and a PEBA solution on the base film. The PEBA composite film provided by the invention has relatively high permeability and relatively high selectivity. The preparation method of the PEBA composite film is simple and easy to control, can be used for the gas separation and pervaporation process, and has wide application prospect.

The invention discloses a method for preparing an oxidizing carbon nitride two-dimensional material composite film. The method comprises the following steps of (1) oxidizing the carbon nitride to obtain oxidizing carbon nitride, dispersing the oxidizing carbon nitride into a solvent, stripping into a flaky shape by ultrasonic waves, and forming oxidizing carbon nitride dispersion liquid; (2) mixing the oxidizing carbon nitride dispersion liquid and macromolecular film forming liquid to form composite film liquid; (3) forming the oxidizing carbon nitride two-dimensional material composite film at the surface of a porous carrier by an impregnating-drying method. The method for preparing the oxidizing carbon nitride two-dimensional material composite film has the advantages that the composite film with adjustable thickness and high mechanical strength can be prepared, and the good selection and separation effects are realized in the field of gas separation.

A composite hollow fibre membrane based on the composite resistance Henis membrane model (silica rubber / polysulfone membrane) for separating H2 or N2 with high effect is composed of basic membrane, water-soluble high-molecular layer in rubber state at ordinary temp and silica rubber layer. It can be used for the ammonia synthesizing plant or oil refinary to recover N2 or H2. Its preparing process is also disclosed.

The invention discloses a method for separating vitamin D3 from tachysterol T3. According to the method, high-purity vitamin D3 and tachysterol T3 are efficiently separated from a mixture containing the vitamin D3 and the tachysterol T3 by a fractional extraction method, wherein a medium polar to polar organic solvent, ionic liquid or a binary mixed solvent consisting of the ionic liquid and the medium polar to polar organic solvent serves as an extracting agent. The method has the advantages of high separation efficiency, low solvent consumption, high yield, safety, environmental friendliness, easiness in industrialized production and the like.

The invention discloses a method for preparing a modified anion exchange membrane with both monovalent selectivity and antibacterial properties. The method comprises the following steps: (1) sequentially carrying out acid washing, alkali washing and water washing on a commercial anion exchange membrane, and removing surface impurities to obtain a pretreated base membrane; (2) forming a uniform poly-dopamine layer on the surface of one side of the pretreated base membrane to obtain an anion exchange membrane with the poly-dopamine layer; (3) carrying out in-situ reduction on silver ions on theanion exchange membrane with the poly-dopamine layer to obtain an anion exchange membrane with nano silver granules and the poly-dopamine layer; (4) dissolving 2,5-diaminobenzene sulfonic acid into aTris buffer solution of which the pH value is 8.5-8.8; (5) soaking the anion exchange membrane with the nano silver granules and the poly-dopamine layer in the 2,5-diaminobenzene sulfonic acid Tris mixed solution, and exposing the nano silver granules and the poly-dopamine layer in ultraviolet lighting to react for 12-24 hours, and grafting the membrane surface with the 2,5-diaminobenzene sulfonicacid to obtain the modified anion exchange membrane.

The invention provides an ionic liquid prepared from dimethylformamide and rhodanate, a corresponding preparation method and an application. The preparation method comprises adding 10 to 20g of kalium rhodanatum or ammonium sulfocyanate colorless crystal into 100mI of N, N-dimethylformamide or of N, N-dimethylacetamide colorless transparent liquid, mixing and reacting for 2-8h in air, under natural light and at 18-25 DEG C until the solution is pink or orange, depressurizing, distilling and purifying the reaction product when the vacuum degree is 0.08 to 0.1 MPa to prepare the ionic liquid. The ionic liquid can be used in extraction separation benzene-cyclohexane / skellysolve C system and extraction distillation separation benzene-cyclohexane / skellysolve C system. The invention has wide diversity of raw material, low cost, easy preparation and simple purification, which is fit for large-scale industrial production and application. The invention realizes better selection separation effect, to provide an excellent quality separating agent for extraction and extraction distillation or the like.

The invention provides a preparation method of a modified cation exchange membrane. The preparation method adopts an alternating current membrane assembly device shown in the figure 1, and comprises following steps: (1), pretreatment is performed; (2), a positively charged monomer layer formed by a reaction of polydopamine and TC is constructed on the surface of the pretreated cation exchange membrane with an alternating current electric field membrane surface assembly technology; (3), a negatively charged polymer layer of PSSMA is constructed on the surface of the positively charged monomer layer with the alternating current electric field membrane surface assembly technology; (4), alternate construction is performed on the membrane surface on the basis of the steps (2) and (3) accordingto the required number of layers, and a modified layer is obtained on the surface of the cation exchange membrane finally; and (5), the modified cation exchange membrane prepared in step (4) is sufficiently soaked in an EDC-HCl and NHS mixed solution, and the modified cation exchange membrane is obtained by washing. The prepared modified cation exchange membrane has good selective separation performance on lithium ions, divalent magnesium ions and calcium ions.

The invention discloses a multi-purpose separation medium and a preparation method thereof, wherein, tetrazole is the functional group of the medium. More particularly, a separation medium with novel structure is prepared by linking the tetrazole on the surface of silica gel, dextran and agarose gel separation group. The invention has dual purposes of being applied to ion-exchange chromatography and metal chelate chromatography. When the medium is applied to the ion-exchange separation of proteins, the separation of proteins is highly selective, easy to regenerate and quick to separate and both the quality and recovery rate of the activity of the proteins are high. When the medium is applied to the metal chelate chromatography of proteins, the separation of proteins is highly selective, small in metal ion loss and quick to separate and both the quality and recovery rate of activity of the proteins are high. The invention can be applied to the quick separation and purification of genetic engineering products and plasma proteins.

The invention provides a hollow fiber nanofiltration membrane based on epsilon-polylysine and a preparation method of the hollow fiber nanofiltration membrane. The hollow fiber nanofiltration membrane based on epsilon-polylysine adopts a hollow fiber membrane as a supporting membrane, and is formed by self-assembling cationic polyelectrolytes and anionic polyelectrolytes containing the epsilon-polylysine layer by layer. The preparation method comprises the following steps: fixing the supporting membrane in a container with a porous supporting layer, allowing the surface of the membrane to face upwards, first pressing, combining and assembling the cationic polyelectrolytes and the supporting membrane to obtain a cationic modification membrane, washing, then pressing, combining and assembling the anionic polyelectrolytes and the cationic polyelectrolytes to obtain an anionic modification membrane, washing, performing heat treatment to obtain a first dual-layer, repeating the foregoing steps to obtain a multilayer modification membrane, finally pressing, combining and assembling the epsilon-polylysine and polyanion electrolyte, and washing to obtain a product. An outermost layer of the hollow fiber nanofiltration membrane is the epsilon-polylysine, so that the antibacterial performance is good, the preparation is simple, the efficiency is high, and the hollow fiber nanofiltration membrane is suitable for actual production.

The invention discloses a method for separating cholesteryl ester from lanolin. The method comprises the following steps of: (1) taking lanolin as a raw material, and preparing a raw material liquid from the lanolin and a hydrophobic organic solvent; carrying out fractional extraction by taking one or more than two mixed solvents from moderate polar or polar organic solvents as extracting agents and a solvent which is the same as the raw material liquid solvent as a washing agent to obtain extraction liquid; and (2) carrying out vacuum concentration, washing with water and drying to obtain the cholesteryl ester. In the method, the organic solvents which are frequently-used in the industry are adopted, and the cholesteryl ester with a higher content can be efficiently separated from the lanolin, so the method has the advantages of high separation efficiency, less solvent consumption, high productivity, low cost, safety, environmental protection, easy industrial production, and the like.

The invention belongs to the technical field of traditional Chinese medicine preparing, and particularly relates to a preparing method for a flower traditional Chinese medicinal material decoction-free preparation and an application thereof. The preparing method includes the steps that after flower traditional Chinese medicinal materials are smashed, supercritical CO2 extraction is carried out; ultrasonic-assisted alcohol extraction is carried out, and ultrasonic-microwave cooperation extraction is carried out; then microfiltration treatment is adopted, finally concentrating, drying, nanometer smashing and packaging are carried out, and the flower traditional Chinese medicinal material decoction-free preparation is obtained. The preparation can be used for preparing a Chinese herbal medicine compound preparation containing flower traditional Chinese medicinal materials or flower traditional Chinese medicinal material extract. By means of the preparing method, the problems that when traditional Chinese medicinal material extraction is carried out with a conventional method, the raw material use rate is low, extraction of effective ingredients is incomplete, and extracting efficiency is low are solved; the whole technological process is easy to control and environmentally friendly, and technological steps synergistic interact with each other, so that the extracting efficiency of the preparing method is higher, the effective ingredients are effectively protected, and the utilization degree of the flower traditional Chinese medicinal materials is increased.

The invention provides an ion exchange composite film with selectivity on a single cation as well as a preparation method and an application thereof. The composite film comprises a cation ion exchange base film and a polyethyleneimine modified layer, wherein the depositing amount of polyethyleneimine on the cation ion exchange base film is 2.0-200.0 g / m<2>; and the thickness of the ion exchange composite film is 50-500 microns. The single cation is Cu<2+>, Zn<2+>, Ni<2+>, Hg<2+>, Ag<2+>, Pt<2+>, Co<2+> and Cr<3+> and the ion exchange composite film can replace the common ion exchange composite films to be mounted in an electrodialyzer. The ion exchange composite film disclosed by the invention has the advantages of simple operation of a preparation method, green and non-toxic preparation process and adaptation to large-scale industrial production.

The invention discloses a method for preparing a polyamide composite film by steam-assisted electrostatic spraying, and belongs to the field of polyamide composite film preparation. The method comprises the following steps: S1, adjusting the relative humidity of the surrounding of electrostatic spraying equipment to 80%-90%; S2, taking an amine monomer solution and an acyl chloride monomer solution as raw materials, and respectively putting the two raw materials into a spraying system of the electrostatic spraying equipment; S3, wrapping a polymer ultrafiltration film on a receiving roller of the electrostatic spraying equipment, setting electrostatic spraying process parameters, and performing electrostatic spraying; and S4, taking down the composite polymer film after electrostatic spraying, and carrying out heat treatment for 5-20 minutes in an environment with the temperature of 50-80 DEG C, so as to obtain a polyamide composite film finished product. The polyamide composite film with narrow pore size distribution can be prepared, the method is simple and easy to implement, the selective separation performance of the film in water treatment can be improved, and the application range of the film is greatly expanded.

The invention discloses a gas chromatographic column for analyzing benzene series. The gas chromatographic column comprises a chromatographic column tube, a supporter and a fixing liquid, wherein thelength of the chromatographic column tube is 1.5 m, the inner diameter of the chromatographic column tube is 3 mm, the supporter is Chromosorb WAW DMCS of 80-100 meshes, the fixing liquid comprises 3.7% of bentonite and 2.3% of dinonyl phthalate, and the chromatographic column tube is a stainless steel tube. Compared with the prior art, effective separation of the benzene series can be realized under a condition that the chromatographic column is shorter, and the gas chromatographic column is convenient, rapid and reliable.

The invention discloses a method for preparing a polyethersulfone hollow fiber gas separation membrane. The method comprises the steps that first, raw material components for preparing a hollow fiberspinning solution are added to a container containing a stirrer in a certain proportion, uniform stirring is performed at a room temperature, then filtration and defoaming are performed, and the spinning solution is obtained; the obtained spinning solution is extruded out by a metering pump through two concentric hollow fiber spinning nozzles, primary fibers are solidified and formed in a water bath with a low temperature of 1-12 DEG C after passing through a distance of 1-20 cm in the air, and then the primary fibers are drawn and wound by a silk take-up reel, and hollow fibers are obtained;and the obtained hollow fiber are washed with water for 2-4 days, and then subjected to solvent exchange and drying to obtain the hollow fiber gas separation membrane. The method is simple in preparation, easy in operation, high in gas preferential segregation and easy in realization of industrialization.

The invention provides a preparation method of a sandwich-shaped heterostructured MOF crystal material having multiple amino functional groups and application of the sandwich-shaped heterostructuredMOF crystal material having multiple amino functional groups to separation of C2H2 / CH4 mixed gas. The preparation method of the MOF crystal material is characterized by comprises the following steps:firstly, synthesizing an MOF crystal A through a hydrothermal method; and removing high-boiling-point solvent molecules in the pores of the crystal A through solvent exchange and vacuumizing; with thecrystal A as a seed crystal, growing a heterostructure MOF crystal B having a sandwich shape and multiple amino functional groups on the surface of the seed crystal A through a hydrothermal synthesismethod; and conducting separation through penetration experiments, and performing vacuum activation at 30 DEG C so as to obtain the sandwich-shaped heterostructured MOF crystal material having multiple amino functional group. The separation factor of the sandwich-shaped heterostructure MOF crystal material having multiple amino functional groups on C2H2 / CH4 / He (wherein a v / v / v ratio is 15: 15: 70, and the total flow of mixed gas is 6 ml / min) reaches 6.54, so the material is a solid adsorption material for efficiently separating C2H2 and CH4.

The invention discloses a preparation method of a self-supporting composite nanofiltration membrane, which comprises the following steps: by taking aminated graphene quantum dots as a main body, preparing a porous graphene-based two-dimensional sheet material through interfacial polymerization reaction between the aminated graphene quantum dots and multi-element acyl chloride; and then in-situ packaging the porous graphene-based two-dimensional sheet material by using polyamide through an in-situ packaging technology to prepare the self-supporting porous graphene / polyamide separation layer with excellent permeability and high selectivity. The self-supporting composite nanofiltration membrane prepared by the method overcomes the Trade-off effect of a traditional polymer membrane material, shows excellent permeation flux, separation performance and dye desalting capacity, has excellent strong alkali resistance and long-term operation stability, obviously prolongs the service life of the membrane, and is suitable for industrial production. The method has good practical value in the fields of industrial wastewater treatment, dye desalination, chemical separation and the like.

The invention discloses a method for separating cholesteryl ester from lanolin. The method comprises the following steps of: (1) taking lanolin as a raw material, and preparing a raw material liquid from the lanolin and a hydrophobic organic solvent; carrying out fractional extraction by taking one or more than two mixed solvents from moderate polar or polar organic solvents as extracting agents and a solvent which is the same as the raw material liquid solvent as a washing agent to obtain extraction liquid; and (2) carrying out vacuum concentration, washing with water and drying to obtain the cholesteryl ester. In the method, the organic solvents which are frequently-used in the industry are adopted, and the cholesteryl ester with a higher content can be efficiently separated from the lanolin, so the method has the advantages of high separation efficiency, less solvent consumption, high productivity, low cost, safety, environmental protection, easy industrial production, and the like.