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.Math.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.Math.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.

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.Math.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.Math.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.

The invention relates to a method for removing Cr(VI) ions from an aqueous electrolyte solution, particularly an electrolyte solution for electrochemical metal machining, which comprises the reduction of Cr(VI) to Cr(III) with Fe(II) ions. The Fe(II) ions are added to the electrolyte solution in the form of an aqueous salt solution which has been brought into contact with an ion exchange resin loaded with Fe(II) ions. The invention further relates to a device (1) for electrochemical machining of a workpiece (2) by means of an aqueous electrolyte solution (6), which has an ion exchanger (11) which has been loaded with an ion exchange resin charged with Fe(II) ions.

The invention relates to a method for removing Cr(VI) ions from an aqueous electrolyte solution, particularly an electrolyte solution for electrochemical metal machining, which comprises the reduction of Cr(VI) to Cr(III) with Fe(II) ions. The Fe(II) ions are added to the electrolyte solution in the form of an aqueous salt solution which has been brought into contact with an ion exchange resin loaded with Fe(II) ions. The invention further relates to a device (1) for electrochemical machining of a workpiece (2) by means of an aqueous electrolyte solution (6), which has an ion exchanger (11) which has been loaded with an ion exchange resin charged with Fe(II) ions.

Disclosed herein are the use of methods and compositions for the simultaneous dehydration of glucose and xylose present in a process relevant biorefinery hydrolysate to furfurals using heterogenous solid acid catalysts.

Disclosed herein are the use of methods and compositions for the simultaneous dehydration of glucose and xylose present in a process relevant biorefinery hydrolysate to furfurals using heterogenous solid acid catalysts.

A polysulfone membrane is modified so that monomers are grafted onto the surface of the membrane. The polysulfone membranes can be grafted by contacting the membrane with a grafting solution and exposing the membrane to electromagnetic radiation, typically within the ultraviolet portion of the spectrum. The monomers that are grafted are typically anionic or cationic. The grafted membranes can be used for filtering impurities, such as positively and negatively charged particles, from a liquid. Anionic membranes provide improved filtration of negatively charged impurities, while cationic membranes provide improved filtration of positively charged impurities.

A polysulfone membrane is modified so that monomers are grafted onto the surface of the membrane. The polysulfone membranes can be grafted by contacting the membrane with a grafting solution and exposing the membrane to electromagnetic radiation, typically within the ultraviolet portion of the spectrum. The monomers that are grafted are typically anionic or cationic. The grafted membranes can be used for filtering impurities, such as positively and negatively charged particles, from a liquid. Anionic membranes provide improved filtration of negatively charged impurities, while cationic membranes provide improved filtration of positively charged impurities.

A method for treating an aqueous fluid resulting from a fluorine-containing polymer production step, the method comprising: separating the aqueous fluid into a solid component and a filtrate using a filter aid.

A method for treating an aqueous fluid resulting from a fluorine-containing polymer production step, the method comprising: separating the aqueous fluid into a solid component and a filtrate using a filter aid.