Jaewon Industrial Co., Ltd

Em-tech Co., Ltd.

Sung Won Shim

Byung Ki Son

Hwan Choi

Tae Gi Choi

Youn Soo Shin

Hwa Yeong Choi

Yeong Su Choo

Ho Jeong

Jae Won Shim

Yung Lim

Min Young Kim

In a method for purifying highly pure isopropyl alcohol used in a semiconductor cleaning process, diacetone alcohol present in isopropyl alcohol is removed by an adsorption process, and diacetone alcohol, triisopropyl borate, and metal impurities are removed by a distillation process. The purified isopropyl alcohol may have a purity of has the moisture of 10 ppm or less, the triisopropyl boron compound of 50 ppt or less, and each metal of the metal impurities of 20 ppt or less.

Purification method of high purity isopropyl alcohol used in semiconductor cleaning process

In a method for preparing a cathode of a secondary battery, a method for preparing a purified N-methyl pyrrolidinone (NMP), and a method for purifying a waste NMP, an inhibitor is added to prevent NMP from being decomposed to produce formaldehyde during the process. 1. The inhibitor may be a phenol-based antioxidant and/or an amine-based light stabilizer.

Method for preparing a cathode of a secondary battery and a purified N-methyl pyrrolidone, and purifying a waste N-methyl pyrrolidone using an inhibitor

Provided is a method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester (AGAECE) for photoresist processing, wherein the method comprises the step of distillation after passing industrial AGAECE through a porous adsorbent impregnated with a basic material, and it is possible to obtain a semiconductor-grade high-purity AGAECE maintaining a low acid value and high purity according to the present invention.

Method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester having high-purity used in photo resist process

A method for purifying a waste N-methyl-2-pyrrolidone (NMP) mixed solution according to an embodiment of the present disclosure includes using a base. The base according to an embodiment may be NaBH. N-methylsuccinimide and γ-butyrolactone are simultaneously removed, and high-purity NMP can be recovered by applying a base to the waste NMP mixed solution.

Method for purifying waste N-methyl-2-pyrrolidone mixture solution

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Jeollanam-do, South Korea

Sung Won Shim