A preparation method of a lanthanum-iron-loaded carbon nanotube film for environmental restoration is provided, it belongs to the technical field of composite materials. The preparation method includes: mixing carbon nanotubes with a lanthanum-iron mixed solution to obtain a suspension, then obtaining a first reaction solution by a constant temperature oscillation reaction; adding alkali liquor into the first reaction solution to obtain a second reaction solution by an oscillation reaction; carrying out a solid-liquid separation on the second reaction solution, adding the obtained solid after drying into an organic solution, and obtaining a third reaction solution by ultrasonic mixing; centrifuging the third reaction solution to obtain a supernatant; obtaining a lanthanum-iron-loaded carbon nanotube film by suction filtration. Compared with powdered adsorbent and single adsorbent, the material prepared by the preparation method has advantages of strong stability, high adsorption efficiency, good regeneration effect, high recycling efficiency, and low production.

A waste water treatment system for removing contaminant chemicals, bacteria and organic matter to reduce the chemical oxygen demand (COD) and the biological oxygen demand (BOD). The system uses thermal energy to remove chemicals that can be oxidized to reduce the COD, and to destroy bacteria and organic matter to reduce the BOD of the treated water. The system can include an expansion chamber and a nozzle to create steam which can be used as thermal energy to heat the waste water and provide the proper treatment to reduce the COD and BOD of the processed waste water.

A preparation method of a lanthanum-iron-loaded carbon nanotube film for environmental restoration is provided, it belongs to the technical field of composite materials. The preparation method includes: mixing carbon nanotubes with a lanthanum-iron mixed solution to obtain a suspension, then obtaining a first reaction solution by a constant temperature oscillation reaction; adding alkali liquor into the first reaction solution to obtain a second reaction solution by an oscillation reaction; carrying out a solid-liquid separation on the second reaction solution, adding the obtained solid after drying into an organic solution, and obtaining a third reaction solution by ultrasonic mixing; centrifuging the third reaction solution to obtain a supernatant; obtaining a lanthanum-iron-loaded carbon nanotube film by suction filtration. Compared with powdered adsorbent and single adsorbent, the material prepared by the preparation method has advantages of strong stability, high adsorption efficiency, good regeneration effect, high recycling efficiency, and low production.

Provided herein are processes for the removal and/or recovery of a target metal from a liquid sample, said process comprising: [1] applying acoustic cavitation to the liquid; and [2] adding an iron (II) salt, or a precursor form thereof, to the liquid sample and allowing Fenton oxidation reaction to occur between the iron and hydrogen peroxide in the liquid, thereby producing hydroxyl radicals; thereby producing a target metal salt or metal oxide having a reduced solubility in the liquid sample, leading to removal of the target metal from the liquid sample. The use of metal ligands in such processes is also described, as well as systems for performing such processes. Methods, processes, and systems for removing organic contaminants from a liquid sample are also described.

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.

The invention relates to a bioactive filter for the disinfection of liquids, in particular water or aqueous solutions in containers. A structure that is advantageous in terms of filter efficiency is obtained by forming a spherical or oval filter body (1), which is coated with noble metals (FIG. 1).

Disclosed is a filter for a water-purification device, the filter including a filter housing having a water inlet and a water outlet defined therein; and a filter member disposed in the filter housing to purify water introduced through the inlet and supply the purified water to the outlet, wherein the filter member includes a carbon block produced by mixing 40 to 50% by weight of titanium oxide, 30 to 40% by weight of activated carbon, and 18 to 23% by weight of binder with each other. Further, a water-purification device including the filter is disclosed.

A waste treatment process utilizes a two-stage digestion process with a thermophilic digester, a heat exchanger, and a mesophilic digester. The pH of the thermophilic digestate is increased by removal of carbon dioxide with an air stripper, or by adding a pH increasing reagent upstream of the heat exchanger. The pH adjustment of the digestate protects the heat exchanger and downstream equipment and processes from struvite formation. A struvite reactor may be located in various locations downstream of the heat exchanger to produce a treated digestate or effluent that contains struvite, which can optionally be recovered for beneficial use.

A rare earth coated membrane is beneficial to aid in the separation of contaminants, such as anions containing phosphorous, anions containing arsenic, PFAS, and mixtures thereof. Membranes with the rare earth coating or treatment can have larger pore sizes than would be expected to remove these contaminants. Disclosed herein are methods for treating or coating the membrane to provide the rare earth coated membrane. The coated membranes can be used to remove contaminants, such as anions containing phosphorous, anions containing arsenic, and PFAS, from liquid feeds, such as water or water-based feeds.

The present invention relates to a method for treating an aqueous liquid effluent containing calcium and carbonate ions and containing precipitation-inhibiting products, said process comprising the following successive steps: a) providing an aqueous liquid effluent supersaturated with CaCO.sub.3 and containing precipitation-inhibiting products; b) having the effluent obtained in step a) pass into a reactor with high solid content with a solid content maintained between 20 and 800 g/l and integrated solid-liquid separation, at a pH comprised between 8 and 9.2 allowing in a single step precipitation in situ of the aragonite polymorph of calcium carbonate and removal of the precipitation-inhibiting products; c) recovering an aqueous liquid supernatant containing a suspended solids content of less than or equal to 0.1% by mass of the solid content in the reactor, advantageously a suspended solids content of less than 50 mg/l, the precipitation-inhibiting products being phosphonates.