9 results about "Catalytic cycle" patented technology

This invention discloses a Co-Mn LDH@N-MWCNT nano-confined catalytic ceramic membrane, its preparation method, and its application, belonging to the field of wastewater purification and advanced oxidation technology. This invention combines Co-Mn LDH and N-MWCNT to form a composite catalyst, which is then loaded onto a porous ceramic membrane, thereby constructing a highly efficient catalytic-separation system. The metal ions in Co-Mn LDH provide abundant catalytic active centers, synergistically activating oxidants to generate free radicals; N-MWCNTs serve as a conductive framework, accelerating electron transport and promoting catalytic cycling, while their nitrogen-doped sites enhance hydrophilicity and dispersibility. Finally, the composite catalyst forms a nano-confined environment within the pores of the porous ceramic membrane, which can efficiently concentrate pollutants and reactants, prolonging their contact time with the active sites, thus achieving in-situ efficient degradation of pollutants during membrane filtration.

The application discloses a supported gold-silver alloy nanocluster composite catalyst and application thereof in catalyzing N-formylation of amine. 13 Ag 12 (PPh2Py) 10 Cl8] + (PF6) ‑ wherein PPh2Py is diphenyl-2-pyridine phosphine. The catalyst is used in N-formylation of amine, the yield reaches 88%, catalytic conditions are mild, the catalyst is easy to recycle and can be used for multiple catalytic cycle experiments, and the catalyst is suitable for various amines, thereby providing a reference for selection of a catalyst for subsequent N-formylation.

The application belongs to the technical field of electrocatalytic hydrogen peroxide production, and particularly relates to a 3D electrocatalytic in-situ hydrogen peroxide generation system and application thereof. The 3D electrocatalytic in-situ hydrogen peroxide generation system comprises a cathode, an anode, an electrolyte and a Co@TriBpy-COF catalyst. The Co@TriBpy-COF catalyst is prepared by the following steps: firstly, synthesizing TriBpy-COF triazine covalent organic framework by a solvothermal method, and then anchoring metal Co by pyridine N to obtain the triazine covalent organic framework anchoring metal Co, i.e. the Co@TriBpy-COF catalyst. The 3D electrocatalytic in-situ hydrogen peroxide generation system promotes the catalytic cycle of Co 2+ → Co 3+ → Co 2+ , greatly improves the hydrogen peroxide yield, so that the catalyst can be reused and the stability of the system is improved.

This invention discloses a polylactic acid (PLA) fiber and its preparation method, relating to the field of PLA fiber technology. The PLA fiber is mainly prepared from the following raw materials in parts by weight: 100 parts PLA, 5-15 parts plasticizer, 0.5-3 parts nucleating agent, 0.5-2 parts anti-hydrolysis agent, 0.05-0.2 parts lubricant, and 0.05-0.1 parts antioxidant. By introducing an anti-hydrolysis agent with a specific structure, and through its synergistic effect with the plasticizer and nucleating agent, the self-catalytic cycle of hydrolysis is effectively blocked, reducing the tendency for molecular chain breakage and performance degradation of the fiber under humid and hot environments. This solves the problems of poor compatibility and insufficient protective effect of anti-hydrolysis agents in existing technologies.

This invention relates to a method for synthesizing phenylhydrazine hydrochloride, belonging to the field of pharmaceutical synthesis technology. Using palladium chloride as a catalyst and sodium ethoxide as a basic agent, under conditions of 50-55°C, an oxidative addition reaction first occurs with the bromine atom on a haloaromatic compound with a bromine atom at the para position, increasing the oxidation state of palladium and forming a highly reactive palladium intermediate. Sodium ethoxide neutralizes the generated hydrogen bromide, driving the reaction forward. The lone pair electrons on the nitrogen atom in hydrazine hydrate attack the palladium intermediate, undergoing a nucleophilic substitution reaction, attaching the nitrogen atom to the carbon atom bonded to the bromine atom. The palladium intermediate then undergoes a reduction reaction, restoring the oxidation state of palladium and generating phenylhydrazine compounds. Simultaneously, palladium chloride is regenerated and can continue to participate in the catalytic cycle. Ethanol serves as the reaction solvent, providing a homogeneous environment for the reaction. Hydrochloric acid is then added to the reaction system, where hydrogen ions combine with the nitrogen atom in the phenylhydrazine molecule to form a stable salt.

This application relates to the fields of molecular sieve synthesis and catalytic chemistry, disclosing a multifunctional titanium-silicon molecular sieve TS-1 nanosheet, its preparation method, and its applications. The nanosheet is prepared from 2 parts of TS-1 nanosheet support, 0-0.026 parts of gold source precursor, and 0-0.028 parts of palladium source precursor. The preparation process involves adding urea to a system containing tetrapropylammonium hydroxide and a silicon source to regulate morphology, adding a titanium source dropwise, and then hydrothermally crystallizing after alcohol removal to obtain the support. The support is then loaded with a metal active component and activated by impregnation. The nanosheet support grows in a confined manner along the b-axis to form a two-dimensional sheet structure. In applications, it catalyzes the in-situ generation of hydrogen peroxide from hydroxide in the same reaction system, and allows it to participate in the cyclohexanone ammoniation reaction to generate cyclohexanone oxime. This invention solves the problems of easy decomposition and storage and transportation safety risks associated with pre-prepared hydrogen peroxide, improves atom utilization and catalytic cycle stability, significantly shortens the process, reduces production costs, and improves process safety.

This invention provides a method for copper-catalyzed Goldberg amination reactions involving piezoelectric materials driven by ball milling, belonging to the field of organic synthesis technology. The mechanical force of ball milling induces the formation of a piezoelectric potential on the surface of the piezoelectric material, which participates in the regulation of the oxidation state of the copper salt catalyst and the catalytic cycle, thereby activating aryl halides and nitrogen-containing nucleophiles. The entire reactant mixture reacts in a ball mill to obtain target products such as N-arylamines or N-arylamides. This invention combines piezoelectric materials with a copper catalytic system, enabling efficient C-N bond construction in copper-catalyzed Goldberg amination reactions under mechanical ball milling conditions without external heating and with little or no solvent. Experiments show that the reaction hardly occurs without the participation of piezoelectric materials, confirming the irreplaceable nature of piezoelectric materials. The method of this invention is mild, environmentally friendly, simple to operate, and has broad substrate applicability, making it suitable for the green construction of the skeletons of N-arylamines or N-arylamides in pharmaceutical, pesticide, and functional material molecules.

This invention provides a method and system for the synergistic recovery of mercury and selenium from acid sludge based on a Fe(III) / Fe(II)-O2 catalytic cycle coupled with selective oxidation. The method includes the following steps: mixing acid sludge, sulfuric acid solution, Fe(III) salt, and chloride to form a redox pair containing Fe(III) and Fe(II) and Cl... ‑ The slurry is leached in the presence of oxygen-containing gas by adding an oxidation initiator and heating to form a catalytic oxidation cycle, thereby obtaining the leaching product. The leaching product is then subjected to solid-liquid separation to obtain leaching residue and a leachate rich in Se(IV) and mercury chloride complex. A reducing agent is added to the leachate to reduce Se(IV) to elemental selenium, and crude selenium product and mercury-containing mother liquor are separated. The mercury-containing mother liquor is then subjected to electrochemical reduction treatment to deposit mercury in the form of elemental metal on the cathode, and the mercury-poor solution is recovered.