The recovery of target species, and related systems and methods, are generally described.

A method of removing organic pollutants in water by zero-valent iron enhanced hypochlorite includes the steps of: adjusting a pH of raw water containing organic pollutants to 4.0˜9.0; adding zero-valent iron solid and hypochlorite to the raw water in a mixer; and turning on the mixer to carry out stirring reaction. The method constructs a Fenton-like system through the redox reaction in the heterogeneous micro-interface region that occurs between zero-valent iron and hypochlorite which produces a variety of active oxidizing species with high occurrence, improves the shortcomings of the traditional Fenton method, broadens the applicable range of pH, and increases the removal efficiency of pollutants in water by 35˜95%.

A composite material for use in water treatment. The composite material includes a porous matrix including a resin capable of retaining a catalyst and magnetic material therein, and includes a density regulating portion disposed therein. The catalyst is capable of facilitating a chemical reaction involving a contaminants in the water. The magnetic material and density regulating portion can be used to separate the composite material from treated water. Systems and methods of use involving passive water treatment, continuous water treatment, solar light exposure, UV light exposure, and electrochemical cells, employing photochemical, electrochemical, and photoelectrochemical reactions are described. Methods of manufacture are described.

Compositions for the adsorptive removal of methyl tertiary butyl ether (MTBE) from contaminated water sources and systems. The compositions contain carbon fly ash doped with silver nanoparticles at specific mass ratios. Methods of preparing and characterizing the adsorbents are described. The composition may contain carbon acid-treated fly ash particles that consist of carbon, oxygen, and sulfur, and have silver oxide nanoparticles present on the surface and in pore spaces of the carbon acid-treated fly ash particles. The composition may be in the form of particles having sizes in a range of 100 nm to 2.5 μm with a BET surface area of at least 16.789 m.sup.2/g, and contain the carbon acid-treated fly ash particles and the metal silver oxide nanoparticles at mass percentages of 50-90% and 10-50%, respectively.

Organized materials on a substrate. The organized materials are monolayer(s) of close-packed nanoparticles and/or microparticles. The organized materials can be formed by transfer of one or more monolayers to a substrate from a coating composition on which a monolayer of close-packed nanoparticles and/or microparticles is formed. Organized materials on a substrate can be used in devices such as, for example, batteries, capacitors, and wearable electronics.

A nanoadsorbent based filter is used for purification of fluoride and arsenic contaminated water. 140-150 g low cost (˜10 USD/kg) nanoparticles of gamma alumina of 20-25 mg/g fluoride and 25-30 mg/g arsenic adsorption capacity is incorporated in propylene filter without susceptibility of leaching incorporated nanoparticles in water. The cost of domestic defluoridation device containing low cost nanoalumina incorporated filters/cartridges along with housing, overhead tank, tubing and treated water storage container etc. is of very low cost of around 25 USD/device. The fluoride treatment cost would be <0.5 USD/100 lit for 4-5 mg/l fluoride water after 2-3 regenerations while, the arsenic treatment cost using domestic filtration device would be <0.25 USD/100 lit for 90-100 μg/l arsenic (III) water. A method incorporates nanoadsorbent in a sediment removal filter candle and provides a household defluoridation device capable of treatment of fluoride and arsenic contaminated ground/drinking water without electricity.

A universal, scalable, solvent-free, one-step method for thermal annealing a stainless steel membrane to create a superhydrophilic surface. The superhydrophilic membrane itself, and methods for using it to separate oil and water in an oil and water mixture or for photocatalytic degradation of methylene blue and other organic contaminants.

A process for the manufacturing of 3D reduced graphene oxide/Fe.sub.2O.sub.3 material includes the following steps: (i) putting in contact a graphene oxide (GO) water dispersion with an aqueous solution of iron(II) sulfate; (ii) hydrothermal treatment; and (iii) freezing the reaction product obtained in step (ii) at a temperature ≤−5° C.; and (iv) lyophilisation. A 3D reduced graphene oxide/Fe.sub.2O.sub.3 material is obtainable by the process and further relates to electrodes for CDI devices having the material. A method for removing ions from a fluid, like saline water, using the capacitive deionization device includes applying a voltage to the electrodes while supplying said fluid into the capacitive deionization device.

A method for removing a fluorine-containing compound from discharge water, which includes bringing discharge water containing two or more fluorine-containing compounds represented by the following general formula (1) or (2) into contact with an adsorbent so as to adsorb the two or more fluorine-containing compounds:

(H—(CF.sub.2).sub.m—COO).sub.pM.sup.1  General Formula (1):

wherein m is 3 to 19, M.sup.1 is H, a metal atom, NR.sup.b.sub.4, where R.sup.b is the same or different and is H or an organic group having 1 to 10 carbon atoms, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent; and p is 1 or 2;

(H—(CF.sub.2).sub.n—SO.sub.3).sub.qM.sup.2  General Formula (2):

wherein n is 4 to 20; M.sup.2 is H, a metal atom, NR.sup.b.sub.4, where R.sup.b is the same as above, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent; and q is 1 or 2.

A process for removing lead from a liquid is provided. The liquid is brought into contact with PbrD proteins having an amino acid sequence which has at least 80% identity to SEQ ID NO: 2, and these proteins bind to lead ions present in the liquid, thus removing the lead ions from the liquid. The bound lead ions are subsequently recovered, such as in the form of an insoluble salt or compound or by cation exchange chromatography, and can then be recycled. The PbrD protein can be immobilized before being brought into contact with the liquid. The proteins are typically immobilized in a matrix of nanoparticles. The PbrD proteins can be recombinantly expressed, such as in a bacterial system (e.g. E. coli) or a yeast expression system.