Filter, metal ion removing method, and metal ion removing apparatus
Assignee3M Innovative Properties Company
InventorsMitsuaki Kobayashi, Yukihisa Okada, Takaaki Shirai, Hideyuki Okada
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Abstract
A filter includes a porous molding, the porous molding being a sintered product of mixed powder containing dry gel powder including an ion exchange resin and thermoplastic resin powder, or a swelled body of the sintered product. When water having an electric resistivity value of 18 MΩ·cm or more is allowed to pass through a space velocity of 1200 hr−1, the electric resistivity value of water after passage is 15 MΩ·cm or more. To provide a filter that can efficiently remove metal ions in a solution to be treated, and easily acquire a solution having an extremely low content of metal ions.
Claims7
A method for removing metal ions in a solution to be treated containing a compound having an acidic group, the method comprising:
- an addition step of adding a strong base to the solution to be treated;
- and
- a passage step of allowing the solution to be treated with the added strong base to pass through a filter comprising a porous molding, the porous molding being a sintered product of mixed powder containing dry gel powder including an ion exchange resin and thermoplastic resin powder, or a swelled body of the sintered product, and when water having an electric resistivity value of 18 MΩ·cm or more is allowed to pass through the filter at a space velocity of 1200 hr−1, the electric resistivity value of water after passage is 15 MΩ·cm or more.
A metal ion removing apparatus comprising:
- a first filter comprising a porous molding, the porous molding being a sintered product of mixed powder containing dry gel powder including an ion exchange resin including at least one type of group selected from a group consisting of an aminophosphate group, an iminodiacetic acid group, and a tertiary amino group and thermoplastic resin powder, or a swelled body of the sintered product;
- and
- a second filter for removing metal ions from solution to be treated that has passed through the first filter,
- the second filter comprising a porous molding, the porous molding being a sintered product of mixed powder containing dry gel powder including an ion exchange resin including a sulfonic group and thermoplastic resin powder, or a swelled body of the sintered product, and when water having an electric resistivity value of 18 MΩ·cm or more is allowed to pass through the filter at a space velocity of 1200 hr−1, the electric resistivity value of water after passage is 15 MΩ·cm or more.
Dependencies are inferred from the claim text.