8 results about "Citrate ion" patented technology

This invention discloses a natural polysaccharide-based multilayer composite encapsulated probiotic and its preparation method, relating to the field of functional food and microbial preparation technology. This invention provides metabolic substrates for the probiotics through a probiotic-prebiotic co-encapsulation core located in the innermost layer, enabling them to maintain physiological activity during encapsulation. The first anionic polysaccharide encapsulation layer uses sodium alginate, which forms a three-dimensional gel network in a calcium-ion-containing curing solution. In the acidic environment of the stomach, the carboxyl groups in the calcium alginate gel undergo carboxylation, and the network shrinks and densifies, effectively blocking the invasion of hydrogen ions and pepsin, thus physically isolating the probiotics from gastric juice. When the encapsulated probiotics enter the small intestine and colon, the chitosan in the second pH-responsive composite encapsulation layer undergoes a conformational change due to amino deprotonation. Simultaneously, phosphate and citrate ions in the outer environment exchange ions with calcium alginate, achieving a triggered release of the probiotics in the colon.

The invention provides a fluorine-reducing and efficiency-improving leaching method for ionic rare earth, and belongs to the technical field of rare earth leaching. According to the method, coordination of aluminum and fluorine ions is reduced through competitive coordination of citrate and aluminum, and therefore the dual purposes of improving the rare earth leaching rate and reducing the fluorine ion leaching amount are achieved. Comprising the steps that a leaching agent A containing citrate ions and an inorganic salt leaching agent B are used for conducting mixed solution leaching or staged leaching on the ionic rare earth ore; the mass concentration range of the component containing citrate ions in the leaching agent A is 0.1-6 wt%, and the concentration of the inorganic salt component in the leaching agent B is 0.01-0.3 mol / L; the mixed solution is formed by mixing a leaching agent A and a leaching agent B, and the leaching agent A and the leaching agent B are adopted for staged leaching in sequence. According to the method, the rare earth concentration in the leachate can be increased, the dosage of the leaching agent is reduced, the fluorine ion leaching amount is reduced, the production requirements of high-quality rare earth products are met, and the application prospect is wide.

A production method for high-purity tetrapropylammonium hydroxide, comprising the following steps: adding tetrapropylammonium halide into a raw material chamber of an electrolytic cell; and by means of electrolysis, tetrapropylammonium cations passing through a cationic membrane, entering a cathode chamber, and being combined with hydroxide ions generated at a cathode, so as to form tetrapropylammonium hydroxide to prepare a quaternary ammonium base. The raw material chamber contains a citrate ion compound. The production method for high-purity tetrapropylammonium hydroxide has the advantage of helping to improve the quality of a quaternary ammonium base product.

The invention belongs to the technical field of metal surface treatment, and particularly relates to a deplating solution for aluminum-manganese alloy and a deplating method. The invention discloses a deplating solution for an aluminum-manganese alloy, which comprises the following components: 30-70g / L of sodium hydroxide; and 20 g / L-70 g / L of sodium citrate. According to the deplating solution for the aluminum-manganese alloy and the deplating method, sodium hydroxide is adopted as a core deplating component, a strong alkaline environment is provided to guarantee that the dissolution reaction of aluminum in an aluminum-manganese alloy coating is efficiently carried out, sodium citrate serves as a key complexing agent, citric acid radical ions dissociated by the sodium citrate are strong multidentate ligands, and therefore the deplating effect is good. According to the stripping solution, through the synergistic effect of the two core components, the technical problems that an existing single sodium hydroxide stripping solution is blocked in stripping and uneven in stripping, a base material is prone to being damaged and the like are solved in a targeted mode, and a reliable solution is provided for efficient and high-quality stripping of an aluminum-manganese alloy coating.

The invention discloses a preparation method and application of a liquid fertilizer containing complexed lignin polymerized phosphorus, and belongs to the field of liquid fertilizer.The preparation method comprises the steps that S1, pH response type gel containing bifunctional modified lignin is prepared, S2, ammonium polyphosphate basic liquid fertilizer is prepared, S3, compounding and complexing are conducted, and S4, a finished product is prepared. Wherein in the step S1, sodium alginate, low-ester pectin and bifunctional modified lignin are mixed in a water phase, a first cross-linking agent is added for a pre-coupling reaction, and a homogeneous polysaccharide-lignin solution is formed; adding a second cross-linking agent to carry out ionic cross-linking to obtain organogel loaded with the bifunctional modified lignin, and carrying out compounding and complexing by utilizing the organogel loaded with the bifunctional modified lignin; the technical problems of phase separation, poor stability, serious phosphorus fixation and rigid release behavior in the liquid fertilizer are solved through the design of bifunctional modified lignin and the synergistic effect of genipin covalent cross-linking and calcium citrate ion cross-linking.

This application discloses a hydrogel with high mechanical strength and its preparation method. A bidirectional photoinitiation system and two-dimensional conductive nanomaterial MXene are introduced into a pregel solution to initiate a free radical polymerization reaction of AAm monomers, generating PAAm chains. Combined with freeze casting, microphase separation occurs using a directionally grown ice crystal induction system, promoting aggregation and entanglement between PVA chains and between PVA and PAAm chains, forming crystalline regions. MXene nanosheets bind to PAAm and PVA chains via hydrogen bonds, constructing a preliminary hydrogel network. The gel is then immersed in a sodium citrate solution. Driven by a concentration gradient, citrate ions form strong coordination with hydroxyl groups on the PVA chains, inducing hydrogen bond cross-linking and well-defined crystalline domains in the pre-concentrated polymer chains, thus enhancing the gel's strength and modulus. The preparation method is simple and efficient, providing an effective strategy for preparing ultra-tough, high-strength, stretchable, and resilient hydrogels.

The application belongs to the technical field of barium compound preparation, and relates to a preparation method of suspended barium sulfate. In the method, magnesium citrate is introduced as a crystal form regulator in the initial stage of the barium sulfate precipitation reaction, and the crystal growth kinetics is cooperatively regulated by magnesium ions and citrate ions, so that flaky or fusiform high-specific-surface-area barium sulfate is obtained. The obtained product has excellent suspension stability, high crystalline purity and good redispersibility without surface modification, and is suitable for water phase and organic medium systems.

The invention belongs to the technical field of metallurgical resource recycling, and particularly relates to a method for high-selectivity separation of phosphorus in steel slag and production of a metallurgical sintering raw material and a phosphate fertilizer. The method comprises the following steps: by taking ammonium citrate as a leaching agent, selectively dissolving a 2CaO. SiO2-3CaO. P2O5 solid solution in the steel slag under a nearly neutral condition by utilizing the strong coordination capability and pH buffer characteristic of citrate radicals of the ammonium citrate to Ca < 2 + >, and meanwhile, inhibiting the dissolution of phases such as calcium ferrite and the like, so that efficient separation of phosphorus and effective retention of calcium and iron are realized; leaching to obtain a phosphorus-rich leaching solution and leaching residues rich in iron and calcium; adding ammonia and precipitating to obtain a phosphate fertilizer, and introducing CO2 to precipitate calcium carbonate; the calcium carbonate and the leached residues are mixed to prepare a metallurgical sintering raw material, and the regenerated leachate can be recycled; the method is operated at the room temperature, steel slag modification is not needed, the phosphorus leaching rate is larger than 90%, the iron leaching rate is smaller than 5%, the alkalinity of the leached slag is larger than 3, all-component resource utilization of the steel slag and zero emission in the technological process are achieved, and remarkable economic and environmental benefits are achieved.