A method of removing boron from water to be treated includes subjecting the water to be treated to reverse osmosis membrane treatment, subjecting at least part of permeated water after the reverse osmosis membrane treatment to cation-removing treatment, and measuring a concentration of boron in the resulting permeated water after the cation-removing treatment, in which a measured value for the concentration of boron is used to regulate at least one of: (a) the recovery rate of water to be treated in the above reverse osmosis membrane treatment, (b) the temperature of the water to be treated, (c) the pH of the water to be treated, (d) the supply pressure of the water to be treated, which pressure is applied to the reverse osmosis membrane during the reverse osmosis membrane treatment, and (e) when the reverse osmosis membrane used for the reverse osmosis membrane treatment should be changed.

Methods of stabilizing virgin ion exchange resin material are provided. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a liquid impermeable compartment of a gas impermeable vessel and hermetically sealing the vessel. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a gas impermeable vessel, introducing an oxygen scavenging material into the gas impermeable vessel, and hermetically sealing the vessel. A method of facilitating water treatment in a site in need thereof by providing rinsed virgin ion exchange resin material in deoxygenated water positioned in a liquid impermeable compartment of a gas impermeable vessel is also provided. A vessel containing deoxygenated water and virgin ion exchange resin material and an oxygen scavenging material is also provided.

Methods of stabilizing virgin ion exchange resin material are provided. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a liquid impermeable compartment of a gas impermeable vessel and hermetically sealing the vessel. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a gas impermeable vessel, introducing an oxygen scavenging material into the gas impermeable vessel, and hermetically sealing the vessel. A method of facilitating water treatment in a site in need thereof by providing rinsed virgin ion exchange resin material in deoxygenated water positioned in a liquid impermeable compartment of a gas impermeable vessel is also provided. A vessel containing deoxygenated water and virgin ion exchange resin material and an oxygen scavenging material is also provided.

Provided is a method for producing ultrapure water to supply, to a use point, ultrapure water obtained by treating raw material water for ultrapure water production in an ultrapure water production apparatus, wherein the raw material water for ultrapure water production contains at least one or more elements selected from B, As, Al, Ti, Cr, Fe, Cu, Zn, Sn, V, Ga, and Pb, and wherein an ion exchanger-filled module filled with at least a monolithic organic porous anion exchanger is installed in a treatment path of the ultrapure water production apparatus or in a transfer path from the ultrapure water production apparatus to the use point, and water to be treated is passed through the ion exchanger-filled module for treatment.

To provide a filter capable of efficiently removing metal ions in a treatment liquid, and capable of easily obtaining a solution having an extremely low metal ion content. A depth filter includes a porous molded article. The porous molded article is a sintered material of mixed powder or a swollen material of the sintered material. The mixed powder contains dried gel powder and thermoplastic resin powder. The dried gel powder contains an ion exchange resin including a sulfonic acid group, and a nitrogen-containing chelating resin.

To provide a filter capable of efficiently removing metal ions in a treatment liquid, and capable of easily obtaining a solution having an extremely low metal ion content. A depth filter includes a porous molded article. The porous molded article is a sintered material of mixed powder or a swollen material of the sintered material. The mixed powder contains dried gel powder and thermoplastic resin powder. The dried gel powder contains an ion exchange resin including a sulfonic acid group, and a nitrogen-containing chelating resin.

A semi-continuous or continuous method and system to improve all phases of ion-exchange resin regeneration such as backwash, resin separation, chemical treatment, slow rinse, fast rinse, resin mixing, and final QA/QC to reduce, reuse and recycle water and chemicals employed in ion-exchange resin regeneration operations. Aqueous media quality is controlled in both backwash as well as ion-exchange resin separation.

A semi-continuous or continuous method and system to improve all phases of ion-exchange resin regeneration such as backwash, resin separation, chemical treatment, slow rinse, fast rinse, resin mixing, and final QA/QC to reduce, reuse and recycle water and chemicals employed in ion-exchange resin regeneration operations. Aqueous media quality is controlled in both backwash as well as ion-exchange resin separation.

Methods of stabilizing virgin ion exchange resin material are provided. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a liquid impermeable compartment of a gas impermeable vessel and hermetically sealing the vessel. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a gas impermeable vessel, introducing an oxygen scavenging material into the gas impermeable vessel, and hermetically sealing the vessel. A method of facilitating water treatment in a site in need thereof by providing rinsed virgin ion exchange resin material in deoxygenated water positioned in a liquid impermeable compartment of a gas impermeable vessel is also provided. A vessel containing deoxygenated water and virgin ion exchange resin material and an oxygen scavenging material is also provided.

Methods of stabilizing virgin ion exchange resin material are provided. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a liquid impermeable compartment of a gas impermeable vessel and hermetically sealing the vessel. The methods include rinsing virgin ion exchange resin material with deoxygenated water, introducing the rinsed virgin ion exchange resin material into a gas impermeable vessel, introducing an oxygen scavenging material into the gas impermeable vessel, and hermetically sealing the vessel. A method of facilitating water treatment in a site in need thereof by providing rinsed virgin ion exchange resin material in deoxygenated water positioned in a liquid impermeable compartment of a gas impermeable vessel is also provided. A vessel containing deoxygenated water and virgin ion exchange resin material and an oxygen scavenging material is also provided.