4results about How to "Fast adsorption rate" patented technology

This invention belongs to the field of wet electronic chemicals technology, specifically relating to a method for preparing electronic-grade hydrogen peroxide. The method includes the following steps: adjusting the concentration of raw hydrogen peroxide, and then filtering it sequentially through a reverse osmosis membrane, a modified cation exchange resin, an anion exchange resin, and a mixed ion exchange resin to obtain electronic-grade hydrogen peroxide. The modified cation exchange resin used is modified based on conventional cation exchange resin through pore expansion and grafting, optimizing the spatial matching of pore structure and functional sites. This achieves passivation of metal ions, enhanced adsorption capacity, and improved oxidation resistance, as well as a deep synergistic effect of these three effects. Ultimately, it achieves the dual goals of efficient purification and stable operation of the resin in the hydrogen peroxide system. The resulting electronic-grade hydrogen peroxide can reduce the content of single impurity metal ions to below 5 ppt, meeting the requirements of SEMI G5 standards, and can be directly applied to high-end manufacturing fields such as semiconductor wafer cleaning.

This invention discloses an adsorption method and apparatus for refined base oil, relating to the field of base oil adsorption technology. The adsorption method proposed in this invention can solve the problem of poor color and short service life caused by the presence of small amounts of gums, asphaltenes, and residual carbon in base oil, without polluting the ecological environment. The adsorption apparatus proposed in this invention includes a reaction chamber; a rotating cylinder is rotatably installed inside the reaction chamber, with a threaded portion on the outer side of the cylinder. The cylinder has a hollow structure, and its interior is divided into two chambers for storing raw materials by a partition. A mixing rod is rotatably installed at the bottom of the cylinder, with its top end communicating with the two chambers. A filter element is vertically slidably installed inside the reaction chamber for quickly filtering precipitates. This adsorption apparatus can accelerate the removal of precipitated substances and improve adsorption efficiency.

This invention discloses a PVDF nanofiber membrane with an in-situ grown strong acid cation exchange layer, its preparation method, and its applications. The preparation method includes: electrospinning to prepare the PVDF nanofiber membrane; after surface activation, in-situ polymerization of a polymer containing sulfonic acid groups (such as polystyrene sulfonic acid) onto the fiber surface. This invention fixes the ion exchange layer to the fiber surface through chemical bonding, ensuring complete exposure of all sulfonic acid groups and eliminating the risk of detachment. The lipophilic segments in the grafted polymer chains significantly improve the wettability of the membrane to organic solvents (such as PGMEA and cyclohexanone), promoting rapid diffusion of metal ions to the exchange sites. When used in semiconductor photoresists or electronic-grade organic solvents, this membrane can deeply remove trace metal ions such as sodium, iron, copper, aluminum, and zinc to below 1 ppb, exhibiting advantages such as fast adsorption rate, high removal rate, and good cycle stability. It has broad application prospects in the field of ultrapure semiconductor wet electronic chemicals.

This invention discloses a thiol-functionalized polyvinyl alcohol (PVA) / sodium alginate (SA)@ZIF-67 composite hydrogel, its preparation method, and its applications. The preparation method uses PVA and SA as matrices, forming hydrogel spheres through ionic crosslinking. After adsorbing cobalt ions, thiol-functionalized ZIF-67 crystals are grown in situ in a mixed ligand solution containing 2-methylimidazole and 2-mercapto-1-methylimidazole to obtain the PVA / SA@SH-ZIF-67 composite hydrogel. This invention achieves efficient adsorption and integrated "adsorption-reduction-fixation" removal of Cr(VI) by introducing thiol-functionalized ZIF-67 into the hydrogel network, utilizing the strong coordination and chemical reduction effects of thiol groups on hexavalent chromium. This composite hydrogel has advantages such as large adsorption capacity, high removal efficiency, and easy separation and recovery, and has broad application prospects in the field of heavy metal wastewater treatment.