An adsorbent for a target compound can include porous carbon particles having pores with a predominant pore size less than 10 nm, and magnetic nanoparticles (MNP) nucleated on the carbon surface and within the pores of carbon particles to provide a carbon magnetic nanoparticle adsorbent (C-MNA). A method for removing target compounds with an adsorbent, a system for removing contaminants from a liquid, and a method for adsorbing target compounds from a fluid are also disclosed.

A method for efficiently removal of oxidised selenium from liquid, such as FGD wastewater. The method involves adding a non-iron-based reducing agent (e.g. sodium dithionite) and preferably Fe(II) ions to the liquid at a pH of above 7.5 or 8 and precipitating elemental selenium from the liquid.

A composition and process for reducing contaminants from water which includes use of a water-insoluble adsorbent having a surface area of at least about 10 m.sup.2/g, where the adsorbent is coated with a water-soluble metal salt.

A compound having the following structure:

##STR00001##

wherein: R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, and R.sup.10 are independently selected from (i) hydrogen atom, (ii) hydrocarbon groups (R) containing 1-30 carbon atoms and optionally substituted with one or more fluorine atoms, (iii) —OR′ groups, (iv) —NR′.sub.2 groups, (v) —C(O)R′ groups, and (vi) halogen atoms, wherein R′ groups are independently selected from R groups and hydrogen atoms, and wherein the R group optionally includes a C(O), ether, or amino linkage; X.sup.m− is an anionic species with a magnitude of charge m, where m is an integer of at least 1; and n is a number, provided that n×m=1. Also described herein are methods for removing one or more oxyanions from a liquid source by use of the above compound or mono-pyridyl derivative thereof.

The present subject matter illustrates a zero-valent metal suspension in non-aqueous phase. The suspension comprises 41 wt. % of a plurality of zero-valent iron particles; 0.1 wt % of a surfactant; 36 wt. % of an oil; and 23 wt. % of a thickening agent.

The present disclosure provides novel solid sorbents synthesized by the reaction of polyamines with polyaldehyde phosphorus dendrimer (P-dendrimer) compounds for metal sequestration. The sorbents are highly stable and exhibit desirable thermodynamics and reaction kinetics with a wide variety of metals including heavy metals and rare earth elements. The sorbents can be easily regenerated for repeated use to extract metals from an aqueous solution. The materials are stable to aqueous and organic media, as well as strong acid and bases. The sorbents maintain full capacity over many cycles of use.

The present disclosure relates to methods of treating water to remove contaminants, including harmful metal ions, and water treatment plants for practicing such methods. In an embodiment, the process includes adding a sulfur-containing, metal-decreasing agent; an iron (III)-containing, metalloid-decreasing agent; forming a solid precipitate from the contaminated water, wherein the solid precipitate includes a solid metal sulfide, a solid iron metalloid, a solid calcium metalloid, or a combination thereof; and separating the contaminated water from the solid precipitate to form purified water.

The present disclosure relates to processes for treating wastewater such as acid rock drainage. The processes may, for example, comprise subjecting the wastewater to a microbial fuel cell process, neutralizing the acid with a base comprising calcium to produce an aqueous composition comprising calcium ions and subjecting the aqueous composition comprising calcium ions to a biological precipitation process to precipitate the calcium ions as calcium carbonate.

A filter for a water purifier includes a filter housing that defines an inlet and an outlet, and a filter module disposed inside the filter housing and configured to purify water received through the inlet and supply purified water to the outlet. The filter module includes a carbon block that includes a mixture of: activated carbon having a weight corresponding to 40 to 50% of a weight of the mixture, a binder having a weight corresponding to 5 to 15% of the weight of the mixture, iron hydroxide having a weight corresponding to 10 to 20% of the weight of the mixture, and titanium oxide having a weight corresponding to 30 to 40% of the weight of the mixture.

A composite comprising a hydroxyapatite and at least one additive which is present during hydroxyapatite synthesis. The additive may be embedded or incorporated into or coated onto the hydroxyapatite. The additive preferably increases the hydroxyapatite porosity, e.g., providing a higher pore volume and/or BET surface area than a hydroxyapatite material without additive. The additive preferably comprises an activated carbon, chitosan, hopcalite, clays, zeolites, sulfur, and/or a metal such as Al, Sn, Ti, Fe, Cu, Zn, Ni, Cu, Zr, La, Ce, in the form of metal, salt, oxide, oxyhydroxide, and/or hydroxide. The hydroxyapatite may be calcium-deficient. The composite is in the form of particles having a D50 of at least 20 μm, a BET surface area of at least 120 m.sup.2/g; and/or a total pore volume of at least 0.3 cm.sup.3/g. An adsorbent material comprising a composite or a blend of composite with a hydroxyapatite without additive, and its use for removal of contaminants such as Hg, Se, As, and/or B from an effluent.