33results about How to "High extraction selectivity" patented technology

The invention discloses application of functional ionic liquid and a method of extracting lithium from salt lake brine and belongs to the technical field of extraction. According to the method, an extraction system organic phase comprises the functional ionic liquid which contains amide groups which are interacted with the lithium, so that interference of other ions can be lowered. Compared with the prior art, the extracting method has the characteristics of low cost, simpleness in operation, high extraction efficiency, cleanness, environmental protection and the like and has an important application value.

The invention discloses an extraction method for cooperating with an aluminum-silicon-lithium-gallium combination method in coal ash. The method comprises the steps of aluminum oxide extraction, wherein pre-desiliconization, dissolving-out through a Bayer method, dissolving-out of sub-molten salt, crystallization and separation, desilicication and seed precipitation are conducted; gallium extraction, wherein adsorption, drip washing, concentration and electrolysis are conducted; lithium extraction, wherein purification, adsorption, desorption, concentration and carbonation sedimentation; preparation of calcium silicate products, wherein causticization of desilicication liquid and dealkalization of desilicication residue are conducted. According to the extraction method, aluminum, silicon,lithium and gallium elements in the coal ash are comprehensively extracted through a whole-wet method, substep and stairstep comprehensive utilization of aluminum, silicon, lithium and gallium is achieved, energy consumption is low, the technological process is simple, the extraction rate of aluminum, lithium and gallium is high, the additional value of solid waste is effectively improved, and themethod is a good comprehensive utilization technology for processing the coal ash through a whole-alkali method and is suitable for industrialization popularization.

The invention discloses nucleic acid aptamer-molecular imprinting synergistic recognition magnetic microspheres and a preparation method and application thereof. The nucleic acid aptamer-molecular imprinting synergistic recognition magnetic microspheres disclosed by the invention comprise magnetic microsphere inner cores and nucleic acid aptamer-molecular imprinting synergistic recognition shells;the nucleic acid aptamer-molecular imprinting synergistic recognition shells have molecular imprinting polymer rigid recognition cavities; the molecular imprinting polymer rigid recognition cavitieshave structural stability, difficult deformation and strong specific adsorptivity; and nucleic acid aptamers are not easy to digest.

The invention provides a technology for separating phycocyanin in spirulina by using polyvinyl ether phosphate through two aqueous phase extraction, belonging to the technical field of biochemical separation engineering. The technology comprises the following steps: preparing polyvinyl ether phosphate; carrying out two phase extraction on phycocyanin; concentrating and freeze-drying, thereby obtaining phycocyanin powder, wherein the phycocyanin recovery rate can be 70-85%. The technology has the beneficial effects that the method is simple; the steps of a purification process are simplified by enriching and separating the spirulina broken wall liquid by directly using polyvinyl ether phosphate; the selectivity is high; the spectral purity of phycocyanin obtained through separation is A620 / A280 which is greater than 2.5; the powder of fresh or dry spirulina can be adopted as a raw material, thus providing a technical method with the effect of solving the problem of high value and large scale utilization of spirulina resources.

The invention relates to the field of recycling of waste lithium ion batteries, and provides a method for recycling lithium from a positive electrode material of a waste lithium ion battery. The method comprises the following steps: mixing the positive electrode material of the waste lithium ion battery with (NH4)2SO4 for sulfating roasting, destroying a layered structure of the positive electrode material so as to smoothly remove lithium ions, and performing water leaching on the roasted product to obtain a lithium-rich leaching solution and a transition metal oxide slag phase. Ammonium carbonate is added into the leaching solution after impurity removal and purification, lithium is recycled in the form of Li2CO3 precipitation at a certain temperature, and the solution is evaporated and crystallized after lithium precipitation to prepare (NH4)2SO4 so that the recycling of the lithium in the positive electrode material of the waste lithium ion battery and the recycling of (NH4)2SO4 are realized, and the lithium-containing residual solution can be recycled in a water leaching stage. The method is short in recycling process, low in cost and clean in process, and the purity of the obtained lithium carbonate is as high as 99.6 wt%.

The invention discloses typhonium giganteum supercritical fluid extract with anticancer activity and a preparation method thereof. The extraction method is characterized in that the active ingredients of dry typhonium giganteum tuber powder serving as a raw material are extracted by using a supercritical fluid extraction technique and by regulating the parameters including flow of CO2, temperatures and pressures of an extraction kettle and a separation kettle and the like. The gas chromatography-mass spectrometer analysis on the extract indicates that the extract contains 40.22 percent of beta-sitosterol and 18.45 percent of campesterol. The results of microbiology and test technology (MTT) tests indicate that the typhonium giganteum extract obtained by the method has obvious tumor inhibition activity for cancer cell lines including colorectal cancer HCT-116, ovarian cancer HO-8910, gastric cancer SGC-7901, liver cancer BEL-7402 and liver cancer SMMC-7721. The extraction method has the advantages of high extraction selectivity, high extraction efficiency, high extraction speed, no pollution to extract, simplicity and convenience for operation, environment friendliness and the like. The extraction method disclosed by the invention can be used for extracting the anticancer active components in the typhonium giganteum and can be used an effective means for extracting sterols.

The invention discloses a preparation method and application of aptamer-modified chitosan nano fibers. The preparation method comprises the following steps: (1) preparing a chitosan solution; (2) preparing chitosan nano fibers; (3) chemical immobilization: taking the aptamer solution, adding an EDC / NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide / N-hydroxysuccinimide) solution for activation, adding the chitosan nano fibers obtained in the step (2), and oscillating to react at normal temperature; and (4) after-treatment: carrying out solid-liquid separation on the reaction mixed solution obtained in the step (3) to obtain the aptamer-modified chitosan nano fibers. The aptamer-modified chitosan nano fibers are suitable for high-selectivity separation and enrichment of trace or ultra-trace mycotoxin substances and other substances in the food and environment, and have the advantages of high selectivity, high extraction capacity, high stability and simple preparation process.

The invention relates to a method for high selectively extracting Artemisia vulgaris essential oil. The method comprises the following steps: (I) drying an Artemisia vulgaris raw material, and crushing into powder; (II) placing the Artemisia vulgaris powder in an extraction tank, vacuumizing to -100 kPa, pouring subcritical butane for extraction into the extraction tank as an extraction solvent, completing soaking a folium artemisia vulgaris sample by using the extraction solvent, adding an entrainer hydrophobic ion liquid [C4C10im]CF3SO3 for extraction, wherein the extraction heat is sourcedfrom a far-infrared generation apparatus arranged on the bottom of the extraction tank, and a glass viewing window is formed on the bottom of the extraction tank; and (III) pumping the liquid solventinto an evaporation tank, decompressing the liquid solvent at a constant temperature, and removing the solvent, thus obtaining the Artemisia vulgaris essential oil. The method has the advantages of simple process, low investment, high efficiency, and capability of producing the high-quality Artemisia vulgaris essential oil with high quality in an industrialization manner.

The invention relates to a composite extractant used in a metal indium extraction process. The composite extractant is formed by mixing Bis(2-ethylhexyl)phosphate (P204), trioctylphosphine oxide and hexylphosphine oxide mixture liquid (C923) and trialkyphosphine oxides (TRPO) according to certain proportion. After being diluted with sulfonated kerosene, the composite extractant is used as an extractant used for metal indium extraction. The composite extractant has good chemical stability, good selectivity and high indium extraction efficiency which can achieve more than 90%, simultaneously can reduce the extractant emulsification, is easy for re-extraction, and the demand to extraction conditions of a system is not high.

The invention discloses a device and a method for the combined use of molecular imprinting solid phase microextraction and hollow fiber liquid phase microextraction, and the application thereof. The device consists of a solid phase microextraction device, a molecular imprinting solid phase microextraction probe, a hollow fiber membrane, an extraction bottle and a stirrer. The molecular imprintingsolid phase microextraction probe is inserted in to a hollow fiber membrane cavity containing organic solvent, fixed and then directly positioned into a sample solution to be measured for purpose of liquid-solid phase synchronous microextraction. During the microextraction, analytes permeate the hollow fiber membrane, are then enriched in the organic solvent and then undergo secondary extraction and enrichment under the action of the molecular imprinting solid phase microextraction probe. The device is simple, operates conveniently, facilitates the combined use with an analyzer, is suitable for the separation and enrichment of organics with trace amounts in complex water phase samples obtained from the fields such as environment, food, medicine, biology and the like.

The invention relates to a composite extractant used in a metal indium extraction process. The composite extractant is formed by mixing Bis(2-ethylhexyl)phosphate (P204), trioctylphosphine oxide and hexylphosphine oxide mixture liquid (C923) and trialkyphosphine oxides (TRPO) according to certain proportion. After being diluted with sulfonated kerosene, the composite extractant is used as an extractant used for metal indium extraction. The composite extractant has good chemical stability, good selectivity and high indium extraction efficiency which can achieve more than 90%, simultaneously canreduce the extractant emulsification, is easy for re-extraction, and the demand to extraction conditions of a system is not high.

The invention provides an extractant composition. The extractant composition comprises the following components in percentage by mass: 20-40% of a phosphate extractant as shown in a formula 1, 35-50%of C6-C10 monohydric alcohol and the balance of a diluent. The invention further provides a resource utilization method of the iron-containing wastewater, and the extractant composition is used in theresource utilization method. The extractant composition disclosed by the invention does not need to use an organic amine extractant, is simple in extraction system and relatively low in cost, and does not easily generate a third phase even under high-concentration iron, so that the extractant composition can be suitable for extraction treatment of various iron-containing wastewater. The resourceutilization method provided by the invention can effectively extract and separate iron from the iron-containing wastewater for resource utilization, is very suitable for large-scale application, and has important economic and social values;.

The invention discloses a method for acquiring lignin with a high phenolic hydroxyl group content from residues after hemicelluloses degradation conversion. The method comprises the following steps: uniformly mixing water, a polar aprotic solvent of a low melting point and a small amount of an alkali so as to obtain an extraction agent, mixing the extraction agent with lignocelluloses formed afterxylooligosaccharide and xylose are extracted or furfural is prepared, increasing the temperature to 150-180 DEG C, conducting a heat-preservation reaction to extract for 90-180 minutes, rapidly decreasing the temperature to 40 DEG C or lower after the reaction is completed, conducting filtration so as to obtain filtrate, washing filter residues twice to three times by using a same type of the polar aprotic solvent which is free of water or alkali and has a same low melting point, completely combining collected filtrate, recycling an organic solvent through distillation, adding 2-3 times of the volume of water into a residual water phase, adjusting the pH value of the solution to 2.0-3.0 by using sulfuric acid, leaving the solution to stand for 2-4 hours to enable lignin to settle down, and conducting filtration, washing and drying on the product, so as to obtain the lignin. By adopting the method, the extraction rate of the lignin in the residues is up to 75% or greater, the loss rateof cellulose in the residues is less than 17%, and high extraction selectivity is achieved for the lignin.

The invention discloses the application of a functional ionic liquid and a method for extracting lithium from salt lake brine, belonging to the field of extraction technology. The organic phase of the extraction system of the method includes a functionalized ionic liquid, and the ionic liquid contains an amide group interacting with lithium, which can reduce the interference of other ions. Compared with the prior art, the extraction method of the present invention has the characteristics of low cost, simple operation, high extraction efficiency, cleanness and environmental protection, and has important application value.

The invention relates to a separation technology for aqueous two-phase extraction of spirulina phycocyanin from polyvinylether phenylacetamide, and belongs to the technical field of biochemical separation engineering. The separation technology comprises the steps of polyvinylether phenylacetamide preparation; two-phase extraction of phycocyanin; phycocyanin powder obtaining after concentration and freeze drying, wherein the protein recovery rate can reach 70 to 85 percent. The method is simple; spirulina wall breaking liquid is subjected to enrichment and separation by directly using the polyvinylether phenylacetamide; the purification process step is simplified; the selectivity is high; the spectrum purity of the phycocyanin obtained through separation achieves the effect that A620 / A280 is greater than 2.5. Raw materials can use fresh spirulina or dry spirulina powder, so that a technology method for realizing high-value large-scale utilization of spirulina resources is provided.

The invention discloses ferroferric oxide magnetic nanometer particles decorated with tetraazacalix [2] arene [2] triazine. A preparation method of the ferroferric oxide magnetic nanometer particles comprises the following steps of: firstly, covering a silicon shell by using the ferroferric oxide magnetic nanometer particles; decorating with amino to obtain amino-modified ferroferric oxide magnetic nanometer particles; and reacting the ferroferric oxide magnetic nanometer particles with the tetraazacalix [2] arene [2] triazine at 110 DEG C under a nitrogen condition to prepare the ferroferric oxide magnetic nanometer particles decorated with tetraazacalix [2] arene [2] triazine. The ferroferric oxide magnetic nanometer particles integrate the advantages of large superficial area of the original and easiness of separation of the original ferroferric oxide magnetic nanometer particles, and also have a new function characteristic, so that the extraction selectivity of a characteristic target is enhanced; and the ferroferric oxide magnetic nanometer particles are used for extracting and separating, and have the advantages of easiness and convenience in operation, and capability of extracting, enriching and separating organic matters and inorganic cations. And moreover, the ferroferric oxide magnetic nanometer particles can be totally separated from a base solution under an external magnetic field function, so that the ferroferric oxide magnetic nanometer particles are economic, environment-friendly and high in recovery rate and have a good popularization and application prospect.

The invention relates to a method for separating an alcohol-water system by extracting through using a hydrophobic Fe-based ionic liquid. The method comprises the following steps: 1, mixing the Fe-based ionic liquid with a C2-C4 alcohol-water solution system under stirring to obtain a mixed solution, wherein the mixed solution comprises 25-47.6mass% of the Fe-based ionic liquid, 4.76-50mass% of alcohol, and the balance; and 2, maintaining the temperature of the mixed solution constant in a range of 273.2-333.2K for dividing the mixed solution into two layers comprising a water phase and an alcohol-extracted Fe-based ionic liquid, and carrying out two-layer separation which means alcohol-water separation, wherein the Fe-based ionic liquid has a structure represented by [R-C3H3N2-R']FeCl4, R is a C4-C8 alkyl group, and R' is a methyl group. The method has the advantages of no need of the adjustment of the pH value of the system or the addition of an organic solvent, good separation effect, low energy consumption, and low saturated vapor pressure, difficult volatilization and harmlessness to the human body of the ionic liquid.

The invention provides a method for preparing a xerogel fixed ligand polymer micro-extraction membrane device. The preparation method comprises the following steps of: directly dispersing a fixed ligand polymer adsorbing agent material into a sol solution by a sol-gel method to prepare silicic acid xerogel of the fixed ligand polymer absorbing material; and further selectively extracting a durable organic pollutant poly-brominated diphenyl ether in the water body and the soil by using the silicic acid xerogel. The preparation method has the characteristics of simple and rapid method, low cost, high stability and heat stability on intensity of the membrane and high sensitivity, rapidness and enrichment efficiency in experiment.

The invention discloses a method for extracting folium artemisiae argyi polysaccharide at high selectivity. The method comprises the following steps of 1, drying folium artemisiae argyi raw materials;then, crushing the folium artemisiae argyi raw materials into folium artemisiae argyi powder; 2, putting the folium artemisiae argyi powder into a sealed extraction tank; performing vacuum pumping toreach -100kPa; injecting distilled water to be used as an extraction solvent; adding an ion liquid carrying agent [C4mim]Cl for extraction; then, performing extraction, wherein the extraction temperature is controlled by an automatic controller; the heat source is a far infrared generating device arranged at the bottom of the extraction tank; 3, pumping a liquid solvent into an evaporating tank;performing constant-temperature reduced pressure desolvation treatment on the liquid solvent in the evaporating tank; obtaining a coarse extract after the liquid solvent desolvation; 4, performing dissolution by a 95-percent ethanol solution; putting the materials into a 4 DEG C refrigerator so that the polysaccharide is completely precipitated; then, performing filtering and freeze drying to obtain the folium artemisiae argyi polysaccharide. The method belongs to the extraction method with the advantages that the process is simple; the investment is low; the efficiency is high; the industrialproduction of high-quality folium artemisiae argyi polysaccharide can be realized.

The invention discloses an extraction method for cooperating with an aluminum-silicon-lithium-gallium combination method in coal ash. The method comprises the steps of aluminum oxide extraction, wherein pre-desiliconization, dissolving-out through a Bayer method, dissolving-out of sub-molten salt, crystallization and separation, desilicication and seed precipitation are conducted; gallium extraction, wherein adsorption, drip washing, concentration and electrolysis are conducted; lithium extraction, wherein purification, adsorption, desorption, concentration and carbonation sedimentation; preparation of calcium silicate products, wherein causticization of desilicication liquid and dealkalization of desilicication residue are conducted. According to the extraction method, aluminum, silicon,lithium and gallium elements in the coal ash are comprehensively extracted through a whole-wet method, substep and stairstep comprehensive utilization of aluminum, silicon, lithium and gallium is achieved, energy consumption is low, the technological process is simple, the extraction rate of aluminum, lithium and gallium is high, the additional value of solid waste is effectively improved, and themethod is a good comprehensive utilization technology for processing the coal ash through a whole-alkali method and is suitable for industrialization popularization.

The invention relates to the field of a medicine for skin external use and specifically discloses an external washing medicine for treating children's prickly heat and a preparation method thereof. The preparation method comprises the following steps: slicing bitter gourd fruit, crushing bitter gourd seeds, and preparing bitter gourd oil and a bitter gourd mixed dry powder by an alkali treatment combined supercritical extraction method; slicing cucumber fruit, and adopting an organic solvent immersion combined supersonic extraction method to obtain a cucumber extract dry powder; and adding water and mixing the bitter gourd oil, the bitter gourd mixed dry powder and the cucumber extract dry powder in any proportion according to age and skin features of children patients so as to prepare the external washing medicine for treating children's prickly heat. Raw material resource by the method is rich, extraction efficiency is high, and there is no organic solvent residue in the product. The obtained medicine can effectively remove prickly heat and is suitable for children of different ages and with different skin features.

The invention discloses a separation technology for two-aqueous-phase extraction of spirulina phycocyanin through polyvinyl ether ampicillin, and belongs to the technical field of chemical separation engineering. The separation technology comprises the following steps: preparation of the polyvinyl ether ampicillin; two-phase extraction of the phycocyanin; obtaining of phycocyanin powder after concentration and freeze drying, wherein the phycocyanin recycling rate can reach 75 to 95 percent. The method is simple; wall breaking fluid of spirulina is enriched and separated by directly using the polyvinyl ether ampicillin, so that the steps in a purification process are simplified; the selectivity is high; the spectral purity of the phycocyanin obtained by separation is up to A620 / A280 greater than 3.5. Fresh spirulina or dry spirulina powder can be used as a raw material, so that a technological method for realizing high-value-scale use of spirulina resources is provided.

The invention discloses a method for separating and purifying resveratrol in polygonum cuspidatum. The method provided by the invention purifies the resveratrol in the polygonum cuspidatum by constructing an alkali ternary two-phase liquid-liquid extracting system; the whole procedure is composed of simple operations including extraction, primary extraction, primary crystallization and the like; the method has the advantages of simplicity in operation, low cost, short purifying period and the like, and does not need an expensive and complicated chromatographic separation device. The resveratrol product prepared by the method has high purity, does not contain acid anthraquinones coexisted component, has no resveratrol loss during a purification process, and has an extracting rate which is higher than that of the traditional method.

The invention relates to a separation technique of Spirulina phycocyanin by polyvinylether aniline double-water-phase extraction, belonging to the technical field of drug separation. The technique comprises the following steps: preparing polyvinylether aniline; carrying out two-phase extraction on phycocyanin; and carrying out concentration and freeze-drying to obtain phycocyanin powder. The protein recovery rate can reach 70-95%. The method is simple: the Spirulina wall breaking solution is directly enriched and separated by using the polyvinylether aniline, thereby simplifying the steps of the purification process. The method has high selectivity; and the spectral purity of the separated phycocyanin reaches A620 / A280>3.5. The raw material can adopt Spirulina fresh algae or dry algae powder, thereby providing a high-value large-scale utilization technique of Spirulina resources.

A method for extracting the essential oil of Artemisia argyi with high selectivity, comprising the following steps: step 1) drying the raw material of Artemisia argyi leaves and pulverizing them into powder; Subcritical butane is injected into the extraction as the extraction solvent, and the extraction solvent completely submerges the Artemisia argyi leaf sample, and the entrainer hydrophobic ionic liquid [C 4 C 10 im] CF 3 SO 3 , the source of extraction heat is the far-infrared generating device placed at the bottom of the extraction tank, and there is a glass window at the bottom of the extraction tank. Step 3) The liquid solvent is pumped into the evaporation tank, and the liquid solvent is subjected to constant temperature and decompression precipitation treatment to obtain the northern mugwort essential oil. The method has the advantages of simple process, low investment and high efficiency, and can industrially produce the extraction method of high-quality northern mugwort essential oil.

The invention discloses a method for refining salvianolic acid A and protocatechuic aldehyde simultaneously. The method employs salvia miltiorrhiza water-extracted concentration as a raw material, and prepares salvianolic acid A and protocatechuic aldehyde by an extraction method. The method is characterized by performing extraction through an alkane-containing mixed solvent. Through changing the ratio of alkanes in the mixed solvent, protocatechuic aldehyde is extracted and separated from the salvia miltiorrhiza water-extracted concentrate, and then salvianolic acid A is extracted and separated. Through water-washing and drying the extract, the high-purity salvianolic acid A and protocatechuic aldehyde can be obtained separately. According to the method, the extracting selectivity can be improved by using alkanes as an extracting agent, and the emulsifying chances in extraction are reduced. The salvianolic acid A and protocatechuic aldehyde can be purified at the same time through extraction only; the method uses no complex operation and has the advantages of simple technique, easiness of amplifying, continuous production, low loss of extracting agents, and the like; therefore, the method is suitable for refining salvianolic acid A and protocatechuic aldehyde simultaneously.

The invention relates to a method for separating an alcohol-water system by extracting through using a hydrophobic Fe-based ionic liquid. The method comprises the following steps: 1, mixing the Fe-based ionic liquid with a C2-C4 alcohol-water solution system under stirring to obtain a mixed solution, wherein the mixed solution comprises 25-47.6mass% of the Fe-based ionic liquid, 4.76-50mass% of alcohol, and the balance; and 2, maintaining the temperature of the mixed solution constant in a range of 273.2-333.2K for dividing the mixed solution into two layers comprising a water phase and an alcohol-extracted Fe-based ionic liquid, and carrying out two-layer separation which means alcohol-water separation, wherein the Fe-based ionic liquid has a structure represented by [R-C3H3N2-R']FeCl4, R is a C4-C8 alkyl group, and R' is a methyl group. The method has the advantages of no need of the adjustment of the pH value of the system or the addition of an organic solvent, good separation effect, low energy consumption, and low saturated vapor pressure, difficult volatilization and harmlessness to the human body of the ionic liquid.

The invention discloses a method for preparing chitosan nanofibers modified by nucleic acid aptamers. The preparation method comprises the following steps: (1) preparing a chitosan solution; (2) preparing chitosan nanofibers; (3) Chemical immobilization: take the nucleic acid aptamer solution, add EDC / NHS solution to activate, then add the chitosan nanofibers obtained in step (2), and shake and react at room temperature; The reaction mixture was subjected to solid-liquid separation to obtain the nucleic acid aptamer-modified chitosan nanofibers. The nucleic acid aptamer-modified chitosan nanofibers of the present invention are suitable for the highly selective separation and enrichment of trace or ultra-trace mycotoxins or other substances in food and the environment, and have high selectivity and high extraction capacity. The advantages of large size, high stability and simple preparation.

The invention discloses nucleic acid aptamer-molecular imprinting synergistic recognition magnetic microspheres and a preparation method and application thereof. The nucleic acid aptamer-molecular imprinting synergistic recognition magnetic microspheres disclosed by the invention comprise magnetic microsphere inner cores and nucleic acid aptamer-molecular imprinting synergistic recognition shells;the nucleic acid aptamer-molecular imprinting synergistic recognition shells have molecular imprinting polymer rigid recognition cavities; the molecular imprinting polymer rigid recognition cavitieshave structural stability, difficult deformation and strong specific adsorptivity; and nucleic acid aptamers are not easy to digest.

The invention relates to a method for separating and recovering phosphoric acid from acetic acid-nitric acid-phosphoric acid series mixed acid waste liquor. The method disclosed by the invention is characterized by comprising the following steps of: an acetic acid-nitric acid extracting step: mixing waste liquor containing acetic acid, nitric acid and phosphoric acid with an extracting agent solution of aliphatic series straight-chain saturated hydrocarbon which contains phosphoric trialkyl ester and 6-13 carbon atoms and selectively dissolving and extracting acetic acid and nitric acid from the extracting agent solution; a phosphoric acid recovering step: recovering the phosphoric acid from extracting waste liquor obtained in the extraction step; and an acetic acid-nitric acid stripping step: enabling the extracting agent solution containing the acetic acid and the nitric acid, obtained in the acetic acid-nitric acid extracting step, to be in contact with stripping water so that the acetic acid and the nitric acid are dissolved and transferred to the stripping water. The extracting agent solution is recycled by feeding the oil-phase extracting agent solution obtained in the acetic acid-nitric acid stripping step to the acetic acid-nitric acid extracting step. By means of the invention, the favorable separability of oil phase and aqueous phase in the stripping step can be maintained for a long time, and the phosphoric acid can be selectively and favorably separated and recovered from the acetic acid-nitric acid-phosphoric acid series mixed acid waste liquor for a long time with high efficiency.