Provided is a method for analyzing the metal impurity content that includes passing water to be analyzed through a monolithic organic porous anion exchanger, thereby allowing the monolithic organic porous anion exchanger to capture metal impurities in the water to be analyzed; passing an eluent through the monolithic organic porous anion exchanger which has been allowed to capture metal impurities in the water to be analyzed, to collect an effluent, thereby obtaining a collected eluent containing metal impurities in the water to be analyzed eluted from the monolithic organic porous anion exchanger; and measuring the content of each metal impurity in the collected eluent.

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.

The present invention provides composite particles which are capable of forming an ion exchange membrane with fewer defects and an ion exchange membrane. The composite particles according to the present invention comprise pellets comprising a fluorinated polymer having groups convertible to ion exchange groups, and a powder held on the pellet surface which comprises a polymer, wherein the powder has an average particle diameter of at least 1 μm and at most 1,000 μm, and the ratio of the average particle diameter of the pellets to the average particle diameter of the powder is 2 to 4,500.

The present invention provides composite particles which are capable of forming an ion exchange membrane with fewer defects and an ion exchange membrane. The composite particles according to the present invention comprise pellets comprising a fluorinated polymer having groups convertible to ion exchange groups, and a powder held on the pellet surface which comprises a polymer, wherein the powder has an average particle diameter of at least 1 μm and at most 1,000 μm, and the ratio of the average particle diameter of the pellets to the average particle diameter of the powder is 2 to 4,500.

Organic sulfur compounds which are generally present in the crude oil undergoes various transformations while processing the crude oil in the secondary processing units such as fluid catalytic cracker, hydrocracker, delayed coker, visbreaker, etc. The sulfur present in the feed which enters into these secondary processing units are distributed into various products coming out of the units. Sulfur compounds which are present in the various product fractions are removed to meet the desired specifications before routing to the final product pool. Conventionally, sulfur present in the LPG has been removed by amine treatment followed by caustic and water wash. The present invention relates to a process for removal of sulfur and other impurities from Liquefied Petroleum Gas (LPG) comprising olefins through reactive desulfurization route. The present invention is an eco-friendly process as it minimizes or eliminates the use of caustic which is conventionally used to remove the sulfur from LPG.

Organic sulfur compounds which are generally present in the crude oil undergoes various transformations while processing the crude oil in the secondary processing units such as fluid catalytic cracker, hydrocracker, delayed coker, visbreaker, etc. The sulfur present in the feed which enters into these secondary processing units are distributed into various products coming out of the units. Sulfur compounds which are present in the various product fractions are removed to meet the desired specifications before routing to the final product pool. Conventionally, sulfur present in the LPG has been removed by amine treatment followed by caustic and water wash. The present invention relates to a process for removal of sulfur and other impurities from Liquefied Petroleum Gas (LPG) comprising olefins through reactive desulfurization route. The present invention is an eco-friendly process as it minimizes or eliminates the use of caustic which is conventionally used to remove the sulfur from LPG.

The present disclosure is directed to methods and systems of purifying solvents. The purified solvents can be used for cleaning a semiconductor substrate in a multistep semiconductor manufacturing process.

In alternative embodiments, the invention provides processes and methods for the recovery, removal or extracting of, and subsequent purification of uranium from a wet-process phosphoric acid using a continuous ion exchange processing approach, where the uranium is recovered from a phosphoric acid, or a phos-acid feedstock using either a dual or a single stage extraction methodology. In both cases an intermediate ammonium uranyl-tricarbonate solution is formed. In alternative embodiments, in the dual cycle approach, this solution is contacted in a second continuous ion exchange system with a strong anion exchange resin then subsequently recovered as an acidic uranyl solution that is further treated to produce an intermediate uranyl peroxide compound which is ultimately calcined to produce the final uranium oxide product. In alternative embodiments, in the single cycle case, the intermediate ammonium uranyl-tricarbonate solution is evaporated to decompose the ammonium carbonate and produce an intermediate uranium carbonate/oxide solid material. These solids are digested in an acid medium, and then processed in the same manner as the secondary regeneration solution from the dual cycle process to produce an intermediate uranyl peroxide that is calcined to produce a final uranium oxide product.