Embodiments of the present disclosure are directed towards methods for preparing mixed-metal oxide particles by heating adamantane-intercalated layered double-hydroxide (LDH) particles at a reaction temperature of from 400° C. to 800° C. to form mixed-metal oxide particles. The adamantane-intercalated LDH particles have a general formula [M.sub.1-xAl.sub.x(OH).sub.2](A).sub.x.mH.sub.2O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate, and an aspect ratio greater than 100. The aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle. The mixed-metal oxide particles comprise a mixed-metal oxide phase containing M, Al or Fe, and carbon.

The present invention relates to a calcined diatomite aggregate coated with metal oxides, more specifically to a diatomite aggregate having a diameter larger than 2 mm.

The invention discloses a core-shell structure polymer magnetic nanosphere with a high Cr (VI) adsorption capacity and its preparation method and application. The preparation method includes: adding Fe.sub.3O.sub.4 powder into a mixed solution of water and ethanol, dispersing Fe.sub.3O.sub.4 powder in the solution evenly by ultrasound, sequentially adding resorcinol and formaldehyde into the suspension to adjust a pH, stirring and reacting to obtain Fe.sub.3O.sub.4@RF evenly dispersed in a chitosan solution, dropwise adding the prepared suspension into a mixed solution of paraffin and span 80, stirring for a period of time, adding a glutaraldehyde aqueous solution, stirring and reacting to obtain a magnetic chitosan nanosphere. The magnetic chitosan nanosphere prepared may be applied to adsorbing Cr (VI) in a water solution. Not only the magnetic chitosan nanospheres prepared has a high adsorption capacity for Cr (VI), but also can be quickly separated by an external magnetic field after adsorption.

The present invention provides a method of reducing and controlling a hazardous substance in a process of high-value biological conversion of an urban organic waste. The method includes: 1) mixing a sludge, a first urban organic waste and an organic acid with water for acclimation to obtain an acclimatized sludge; 2) stage 1 of biological conversion: mixing the acclimatized sludge with a second urban organic waste to perform anaerobic culture; 3) stage 2 of biological conversion: adding nitrate and bacteria to continue anaerobic culture so as to obtain an organic acid. In the present invention, sludge microbes are acclimatized and then added to high-value chemicals such as acetic acid, propanoic acid and lactic acid prepared in biological conversion of the urban organic waste and then added with bacteria. Thus, by controlling pH value, microbe addition amount and nitrate concentration, the unfavorable effect of the antibiotics and heavy metal ions.

Disclosed are systems and processes for the removal and conversion of pollutants in water. A system includes a set of electrodes with at least one electrode having an integrated catalyst material. The system is operatable in a first, electrodialysis mode in which one or more pollutants are separated from a feedwater stream, and a second electrolysis mode in which the separated pollutant(s) are catalytically converted into benign products by way of the catalyst material of the electrode. Electrodialysis and electrolysis are therefore carried out using the same unit.

Provided are an extract, which is a fractionated component 1 of a water extract of a plant powder, wherein the fractionated component 1 is a fractionated component having a fractionation molecular weight of 12,000 or greater, wherein an ethanol-undissolved component of the fractionated component 1 exhibits a peak attributable to carboxylic acid in a Fourier transform infrared spectroscopy (FT-IR) measurement and exhibits a peak attributable to cellulose in a gas chromatography mass spectrometry (GC-MS) measurement, and wherein an ethanol-dissolved component of the fractionated component 1 exhibits a peak attributable to carboxylic acid in the FT-IR measurement and exhibits a peak attributable to a plant protein in the GC-MS measurement, and a water-purifying agent containing the extract.

A method for treatment of mixed electroplating wastewater without a cyanide and a phosphorus-containing reductant without a cyanide and a phosphorus-containing reductant. A ferrous chloride solution is added into electroplating wastewater without a cyanide and a phosphorus-containing reductant. The pH of wastewater is adjusted to 10.5-12. Pollutants such as sodium cyanide and hydroxyl-containing organic amine complexants are oxidized with sodium hypochlorite. Carboxyl-containing organic acid complexants are precipitated. Hexavalent chromium is reduced to trivalent chromium to form chromium hydroxide precipitate. Precipitate is removed by filtering and wastewater is adjusted to pH 4.5-5.5. Heavy metal ions are precipitated with sodium dimethyldithiocarbamate or sodium diethyldithiocarbamate. Precipitate and heavy metal capturing agents are adsorbed with activated carbon followed by removal of precipitate. Wastewater is adjusted to pH 6-8. Aliphatic polyamine complexants are destroyed using an available biological degradation technique to reduce chemical oxygen demand.

A filter material composing a ceramic clay having an interconnected network of pores formed from cellulose fiber combustion is useful for removing chemical and biological contaminants from a water supply. Coating the ceramic clay with lanthanum enhances the removal of anionic species of As(V), As(III), Cr(VI), microbes and virus.

An adsorbent includes a porous substrate and a carboxylic acid dimer loaded onto the porous substrate. The carboxylic acid dimer is loaded on the surface or in the plurality of holes of the porous substrate. The average pore size of the porous substrate is not smaller than 2 nm. The carboxylic acid dimer is loaded onto the porous substrate by at least one of the following manners: a) the carboxylic acid dimer is loaded onto the porous substrate through a Si—OH bond; b) the carboxylic acid dimer is loaded onto the porous substrate through the exchange between a carboxyl group and chlorine; c) the carboxylic acid dimer is loaded onto the porous substrate through the exchange between a carboxyl group and a hydroxyl group; and d) the carboxylic acid dimer is loaded onto the porous substrate through the coordination of a carboxyl group and aluminum or silicon.

An organic polymer composition (OPC) comprising guanidinium-containing A units interconnected with B units of the formula *—R*).sub.r, wherein each asterisk (*) in A units denotes a connection point with an asterisk in B units; R is a hydrocarbon linking group containing at least one carbon atom; r is an integer of 1, 2, or 3; and the composition necessarily includes an anionic species X.sup.m− with a magnitude of charge m of at least 1, wherein the sum of negative charge provided by anionic species X.sup.m− counterbalances the total positive charge provided by the A units. Also described herein is a method for removing one or more oxoanions from an aqueous source by (i) contacting the aqueous source with the above described OPC to result in absorption of the oxoanion into the OPC to produce an oxoanion-containing OPC; and (ii) removing the oxoanion-containing OPC from the aqueous source.