A crosslinked polymer that is in the form of a Mannich polycondensation product including reacted units of a cyclic diaminoalkane, an aldehyde, and bisphenol-S or melamine. Also disclosed is a method for removing heavy metals from an aqueous solution by contacting the aqueous solution having an initial concentration of the heavy metal with the crosslinked polymer to form a mixture, and filtering the mixture to obtain an aqueous solution having a reduced concentration of the heavy metal compared to the initial concentration.

A preparation method of a resin-based iron oxide-containing composite phosphate removal adsorbent is provided. An alkaline anion resin is taken as a base, a potassium ferrate is used as an iron source, and a characteristics of ferrate ions easily adsorbed on a surface of the anion resin are utilized to prepare resin-based iron oxide-containing composite phosphate removal adsorbent by one-step in-situ hydrolysis precipitation, compared with the related art, a preparation process of the disclosure is relatively simpler, a time period is shorter, and a production cost is lower. It has a strong ability to eliminate interference from other anions in the waste effluents, and it has a strong adsorption capacity, fast adsorption speed and large adsorption capacity for the phosphate. Moreover, it has the advantages of strong regeneration ability and multiple repeated use times.

A system and method for generating base water and precipitate, including combining produced water with seawater to precipitate barium sulfate from barium in the produced water and from sulfate in the seawater, and separating the precipitate to give the base water and the precipitate. The base water may have less than a specified amount of sulfate and be utilized for hydraulic fracturing fluid. The precipitate may give a weighting agent for drilling.

An absorbent is provided, which is produced from component A, a foaming agent, and component B, a resin. Furthermore, a device and a method for producing the absorbent and a method for absorbing a liquid by means of the absorbent are provided.

A composite material is provided comprising a porous polymeric matrix having metal-organic framework (MOF) domains dispersed within the porous polymeric matrix, each of said MOF domains in fluid communication with the external environment through the pores in the porous polymeric matrix. A process of using the composite material to chemically modify or detoxify a chemical warfare agent or a toxic industrial chemical is also provided. The chemical warfare agent or the toxic industrial chemical is brought into contact with a MOF domain within the porous polymeric matrix so that the MOFs adsorb and chemically modify the chemical warfare agent or the toxic industrial chemical. A process for producing such a composite material is also disclosed.

A filter includes a porous molded article, which is a sintered material of mixed powder containing activated carbon powder and thermoplastic resin powder. When water having a specific electrical resistance value of 18 MΩ.Math.cm or greater is caused to pass through the filter at a space velocity of 1200 hr.sup.−1, a specific electrical resistance value of the water after being caused to pass through the filter is 13 MΩ.Math.cm or greater. 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.

Composite materials for removing hydrophobic components from a fluid include a porous matrix polymer, carbon nanotubes grafted to surfaces of the porous matrix polymer, and polystyrene chains grafted to the carbon nanotubes. Examples of porous matrix polymer include polyurethanes, polyethylenes, and polypropylenes. Membranes of the composite material may be enclosed within a fluid-permeable pouch to form a fluid treatment apparatus, such that by contacting the apparatus with a fluid mixture containing water and a hydrophobic component, the hydrophobic component absorbs selectively into the membrane. The apparatus may be removed from the fluid mixture and reused after the hydrophobic component is expelled from the membrane. The composite material may be prepared by grafting functionalized carbon nanotubes to a porous matrix polymer to form a polymer-nanotube composite, then polymerizing styrene onto the carbon nanotubes of the polymer-nanotube composite.

The present invention relates to a process for selectively removing a first charged species from a plurality of charged species in solution, which process comprises: treating a solution with a functionalised polymer and a surfactant, wherein the solution comprises a plurality of charged species dissolved in a solvent, wherein the plurality of charged species comprises the first charged species and at least one further charged species which is different from the first charged species, and wherein the functionalised polymer comprises groups that bind preferentially to the first charged species.

A smart sand includes raw sand particles, synthetic SiO.sub.2 particles attached to the raw sand particles, a first material attached to a first set of the synthetic SiO.sub.2 particles, a second material attached to a second set of the synthetic SiO.sub.2 particles, and a third material attached to the first material. Each of the first to third materials is different from each other.

A nucleophilic substitution reaction to crosslink cyclodextrin (CD) polymer with rigid aromatic groups, providing a high surface area, mesoporous CD-containing polymers (P-CDPs). The P-CDPs can be used for removing organic contaminants from water. By encapsulating pollutants to form well-defined host-guest complexes with complementary selectivities to activated carbon (AC) sorbents. The P-CDPs can rapidly sequester pharmaceuticals, pesticides, and other organic micropollutants, achieving equilibrium binding capacity in seconds with adsorption rate constants 15-200 times greater than ACs and nonporous CD sorbents. The CD polymer can be regenerated several times, through a room temperature washing procedure, with no loss in performance.