Dry ion exchange resin manufacturing method and manufacturing device, and treatment target liquid purifying method and purifying device

A dry ion exchange resin manufacturing method comprising:

• obtaining a purified cation exchange resin by bringing a cation exchange resin that represents a purification target into contact with a mineral acid solution having a metal impurity content of not more than 1 mg/L and a concentration of at least 5% by weight to purify the cation exchange resin, wherein a total metal impurity elution amount eluted when hydrochloric acid with a concentration of 3% by weight is passed through the purified cation exchange resin with a volume ratio of 25 times is not more than 5 μg/mL-R;
• and
• drying the purified cation exchange resin under reduced pressure at 80° C. or lower until a moisture content is not more than 5% by weight to obtain a dry cation exchange resin,
• wherein the cation exchange resin is at least one of a H-form chelating resin and a weak cation exchange resin,
• wherein the chelating resin has aminomethylphosphonic acid groups or iminodiacetic acid groups as chelating groups, and
• wherein the dry cation exchange resin is used for purification of a hydrolyzable solvent in which a metal concentration following purification is not more than 1 ppb for each metal.