Abstract: Methods for producing economical antimicrobial and antifungal nanoparticle composites are presented. The method includes converting chitosan or derivative thereof to nanoparticles by ionotropic gelation process and the nanoparticle composite in the presence of a process solution without any separation process to isolate the nanoparticles prior to application. The composition containing chitosan nanoparticles, ionotropic gelation agent, a nonionic surfactant, and an active halogen provides improved disinfectant and fungicidal properties against bacterial, viral and fungal contaminants along with prolonged residual effects. Methods and systems for decontamination, wound healing and plant growth enhancements are also presented.

Abstract: Methods for producing or regenerating an iodinated anion exchange resin are presented. The methods include treating an iodide loaded anionic resin with an aqueous solution comprising an in situ formed I2 to produce the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to resins produced by conventional methods. Methods and systems for purifying water are also presented.

Abstract: Methods for producing or regenerating an iodinated resin are presented. The methods include converting iodide residues on a surface of and in pores of an iodide loaded anion exchange resin to iodine and iodine intermediates using a source of active halogen to form an iodinated resin having iodine and iodine intermediate residues on the surface of and in the pores of the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to conventional iodinated anion exchange resins and may utilizes less iodine raw materials during the manufacturing process. The iodinated resin can also act as an end-of life indicator in a water purification system that incorporates the iodinated resin to reduce microbial, including bacterial and viral, contamination in drinking water sources. Methods and systems for purifying water are also presented.

Abstract: A filter to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, a filter material comprising chitosan or a derivative thereof intermediate the halogen release system and the outlet, and a scavenger barrier intermediate the filter material and the outlet. The filter material may comprise a chitosan-halogen complex. The filter material is capable of regeneration during periods of stagnation. The filter may have a Log reduction value for viruses of at least 4 and a Log reduction value for bacteria of at least 6.

Abstract: Methods for producing or regenerating an iodinated resin are presented. The methods include converting iodide residues on a surface of and in pores of an iodide loaded anion exchange resin to iodine and iodine intermediates using a source of active halogen to form an iodinated resin having iodine and iodine intermediate residues on the surface of and in the pores of the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to conventional iodinated anion exchange resins and may utilizes less iodine raw materials during the manufacturing process. The iodinated resin can also act as an end-of life indicator in a water purification system that incorporates the iodinated resin to reduce microbial, including bacterial and viral, contamination in drinking water sources. Methods and systems for purifying water are also presented.

Abstract: Methods for producing or regenerating an iodinated anion exchange resin are presented. The methods include treating an iodide loaded anionic resin with an aqueous solution comprising an in situ formed I2 to produce the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to resins produced by conventional methods. Methods and systems for purifying water are also presented.

Abstract: A water treatment system may generally comprise a generally cylindrical halogenated resin bed comprising an empty bed contact time greater than 1 second, an aspect ratio less than 0.8, and a fluid velocity less than 0.5 cm/s, wherein the aspect ratio is the ratio of the length of the halogenated resin bed to the diameter of the halogenated resin bed; and wherein the fluid velocity is the quotient of the volumetric flow rate of the water treatment system and the cross-sectional area of the halogenated resin bed; and wherein the halogenated resin bed improves the removal of contaminates relative to a corresponding water treatment system having an aspect ratio greater than 0.8.

Abstract: Methods for preparing a chitosan-based material for use in a halogen water treatment system are described. Treating chitosan or chitin with a compound selected from the group consisting of an acid, a base, a mild halogenating solution and combinations thereof provides a chitosan-based material that displays reduced leakage of halide ion. Water treatment systems and methods for treating water comprising at least one contaminant are also described.

Abstract: The water treatment systems may generally comprise multiple halogens and chitosan or derivatives thereof as well as methods of making and using the same. A water treatment system to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, and a halogenated chitosan intermediate the halogen release system and the outlet. The system may comprise a scavenger barrier intermediate the halogenated chitosan and the outlet. The halogen release system may comprise a first halogen having a first oxidizing potential. The halogenated chitosan may comprise a second halogen having a second oxidizing potential. The second oxidizing potential is greater than the first oxidizing potential.

Abstract: A filter to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, a filter material comprising chitosan or a derivative thereof intermediate the halogen release system and the outlet, and a scavenger barrier intermediate the filter material and the outlet. The filter material may comprise a chitosan-halogen complex. The filter material is capable of regeneration during periods of stagnation. The filter may have a Log reduction value for viruses of at least 4 and a Log reduction value for bacteria of at least 6.

Abstract: A low pressure point-of-use water treatment system may generally comprise at least one inlet port in fluid communication with at least one outlet port to establish a fluid pathway therethrough; an iodinated resin intermediate the at least one inlet port and at least on outlet port, wherein the iodinated resin transfers iodine into the fluid pathway for a volume of water corresponding to an effective life of the iodinated resin; and an ion exchange resin intermediate the iodinated resin and the at least one outlet port, wherein the ion exchange resin removes at least a portion of the iodine transferred by the iodinated resin into the fluid pathway for a volume of water corresponding to a breakthrough point as measured by iodide leakage; and wherein the ion exchange resin inactivates contaminants in the fluid pathway as the iodinated resin nears the end of its effective life.

Abstract: The present disclosure generally relates to filter media compositions, apparatuses and systems for removing contaminants from fluids, as well as methods of using the same. In certain aspects the filter media comprises one or more halogenated resins and one or more contaminant sorbent media. The filter media of the present disclosure may be self-contained in a single unit or certain components may be housed in separate units acting in parallel or in series.