Water treatment device and water treatment method

A water treatment device comprising:

• a hydrogen-adding device for adding hydrogen to water being treated that contains at least hydrogen peroxide;
• and
• an oxidizing substance-removing device into which flows the water being treated to which hydrogen has been added by the hydrogen-adding device, wherein
• the oxidizing substance-removing device comprises:
• a catalyst device provided with a catalyst metal-supporting resin for removing hydrogen peroxide from the water being treated through contact with the water being treated to which hydrogen has been added by the hydrogen-adding device;
• a concentration-measuring means for measuring the concentration of dissolved hydrogen in the water being treated that has been treated by the catalyst device;
• and
• a control means for regulating the amount of hydrogen added by the hydrogen-adding device on the basis of the concentration of dissolved hydrogen measured by the concentration-measuring means, and wherein
• the catalyst metal-supporting resin is a catalyst metal-supporting resin in which a platinum group metal catalyst is supported on a carbonate-type anion exchange resin.