Diluted chemical liquid production apparatus capable of controlling pH and oxidation-reduction potential

Patent metadata

Field	Value
Publication number	US-11325851-B2
Application number	US-201716492947-A
Country	US
Kind code	B2
Filing date	Sep 12, 2017
Priority date	Mar 30, 2017
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

A diluted chemical liquid production apparatus has a structure that has a platinum group metal carrying resin column, a membrane-type deaeration apparatus and a gas dissolving membrane apparatus, which are sequentially provided in a supply line of ultrapure water; and has a pH adjuster injection device and an oxidation-reduction potential adjuster injection device, which are provided between the platinum group metal carrying resin column and the membrane-type deaeration apparatus. An inert gas source is connected to a gaseous phase side of the membrane-type deaeration apparatus, and an inert gas source is also connected to the gaseous phase side of the gas dissolving membrane apparatus; and a discharge line communicates with the gas dissolving membrane apparatus. A pH meter and an ORP meter are provided in the discharge line. Such a diluted chemical liquid production apparatus can control a pH and an oxidation-reduction potential.

First claim

The invention claimed is:

1. A diluted chemical liquid production apparatus comprising:
a platinum group metal carrying resin column and a membrane type deaeration apparatus, which are sequentially provided in an ultrapure water supply line; and
a pH adjuster injection device for adding a pH adjuster into ultrapure water and an oxidation-reduction potential adjuster injection device for adding an oxidation-reduction potential adjuster, which are provided between the platinum group metal carrying resin column and the membrane type deaeration apparatus, and a diluted chemical liquid is obtained by adding the pH adjuster and the oxidation-reduction potential adjuster into ultrapure water;
wherein the membrane type deaeration apparatus includes a liquid phase chamber for passing the diluted chemical liquid and a gaseous phase chamber for removing a gas dissolved in the diluted chemical liquid composed by a hydrophobic gas permeable membrane;
wherein an inert gas is provided into the membrane type deaeration apparatus, and
wherein a final diluted chemical liquid is obtained by passing ultrapure water through the platinum group metal carrying resin column, the pH adjuster injection device, the oxidation-reduction potential adjuster injection device and the membrane type deaeration apparatus.

2. The diluted chemical liquid production apparatus according to claim 1 , comprising a gas dissolving membrane apparatus for receiving the diluted chemical liquid deaerated by the membrane type deaeration apparatus.

3. The diluted chemical liquid production apparatus according to claim 1 , comprising pH measuring means and oxidation-reduction potential measuring means for measuring the diluted chemical liquid deaerated by the membrane type deaeration apparatus.

4. The diluted chemical liquid production apparatus according to claim 1 , wherein the pH adjuster is ammonia, and the oxidation-reduction potential adjuster is hydrogen peroxide.

Assignees

• Kurita Water Ind Ltd

Inventors

• FUJIMURA Yu
• GAN Nobuko

Classifications

• B01D61/00

  Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor (separation of gases or vapours by diffusion B01D53/22) · CPC title

• C02F2103/04

  for obtaining ultra-pure water · CPC title

• C02F2209/06

  pH · CPC title

• C02F2103/346

  from semiconductor processing, e.g. waste water from polishing of wafers · CPC title

• C02F1/66 Primary

  by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) · CPC title