3 results about "Cyclohexanediaminetetraacetic acid" patented technology

The application discloses a preparation process of electronic-grade trans-1,2-cyclohexanediaminetetraacetic acid. The preparation process takes industrial-grade 1,2-cyclohexanediamine as raw material, reacts the 1,2-cyclohexanediamine with electronic-grade organic acid to generate a water-soluble salt, crystallizes at 0-30 DEG C, filters out the crystal to reserve the filtrate, adds an alkaline solution to the filtrate, then adds a polar organic reagent to extract, directly adds an aqueous bromoacetic acid solution to the oil phase to react, after the reaction is completed, adds electronic-grade dilute acid to precipitate trans-1,2-cyclohexanediaminetetraacetic acid until the PH of the system is less than or equal to 2, filters and reserves the solid, washes with pure water, and electronic-grade trans-1,2-cyclohexanediaminetetraacetic acid is obtained. The method has a clear process route, can effectively remove metal ion impurities in the synthesis process, the obtained trans-1,2-cyclohexanediaminetetraacetic acid product has high purity, can be used for preparing high-end semiconductor cleaning liquid, and meets the strict requirements of advanced processes on the purity of cleaning chemicals.

The application discloses an organic alkali cleaning solution and a multistage coupling cleaning method for SiC shower heads, and belongs to the technical field of semiconductor component wet cleaning. The organic alkali cleaning solution comprises an organic quaternary ammonium compound, an organic alcohol amine, a chelating agent, an ammonium salt corrosion inhibitor and a fluorocarbon surfactant; wherein the chelating agent is a mixture of trans-cyclohexanediaminetetraacetic acid and diethylenetriaminepentaacetic acid. The multistage coupling cleaning method for SiC shower heads comprises the steps of sequentially performing isopropyl alcohol immersion ultrasonic cleaning, organic alkali cleaning solution immersion ultrasonic cleaning and pure water ultrasonic cleaning, and then combining micro-nano bubble cleaning. The selected organic alkali cleaning solution comprises a three-component synergistic system of trans-cyclohexanediaminetetraacetic acid, diethylenetriaminepentaacetic acid and ammonium citrate. The use of the chelating agent produces a significant synergistic chelation effect on various metal ions, and the ammonium citrate simultaneously plays multiple functions of corrosion inhibition, auxiliary chelation and particle dispersion, which helps to significantly improve the cleaning effect.

The application discloses a method for determining the content of soluble anions in bauxite, which comprises the following steps: extracting a bauxite sample by using an alkaline extracting solution containing cyclohexanediaminetetraacetic acid to obtain a to-be-tested solution; and determining the soluble anions in the to-be-tested solution by using an ion chromatography method, wherein the eluent used in the ion chromatography method is an alkaline eluent, and the detection mode used in the ion chromatography method is a suppressed conductivity detection mode; the soluble anions include any one or more of F ‑ , Cl ‑ , SO4² ‑ and NO3 ‑ . The method provided by the application can significantly improve the extraction efficiency and detection accuracy of the target anions, and can simultaneously determine multiple target anions.