A preparation method of a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material includes: (1) etching Ti.sub.3AlC.sub.2 with LiF/HCl to prepare two-dimensional transition metal carbide nanosheet; (2) preparing a nanosheet aggregate by electrostatic self-assembly of a two-dimensional transition metal carbide nanosheet and a positively charged nitrogen-containing cationic compound; (3) calcining the nanosheet aggregates to prepare a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material. A method for degrading and removing organic pollutants in water includes (1) etching Ti.sub.3AlC.sub.2 with LiF/HCl to prepare two-dimensional transition metal carbide nanosheet; (2) preparing a nanosheet aggregate by electrostatic self-assembly of a two-dimensional transition metal carbide nanosheet and a positively charged nitrogen-containing cationic compound; (3) calcining the nanosheet aggregates to prepare a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material; (4) placing the two-dimensional nitrogen-doped carbon-based titanium dioxide composite material into water containing organic pollutants to degrade and remove organic pollutants in water.

Methods to remediate a contaminated material are provided. In one embodiment, a biocatalyst that digests hydrocarbon contaminants is activated with a nutrient and the activated biocatalyst is combined with the contaminated material and water to form a mixture. The mixture is incubated for a period of time, and the level of contaminant in the mixture is determined to ascertain whether to incubate further, add additional biocatalyst mix, or provide the remediated material for further processing. In one embodiment, the remediated material is provided for reuse or recycling with a second material, such as a construction aggregate. The method is particularly suited for remediation of drill cuttings, mine tailings, hydrocarbon-contaminated soil, and the like.

The present invention discloses a bismuth oxide (Bi.sub.2O.sub.3)/bismuth subcarbonate ((BiO).sub.2CO.sub.3)/bismuth molybdate (Bi.sub.2MoO.sub.6) composite photocatalyst, including a Bi.sub.2MoO.sub.6 photocatalyst, where Bi.sub.2O.sub.3 and (BiO).sub.2CO.sub.3 nanosheets are introduced to a surface of the Bi.sub.2MoO.sub.6 through addition of Na.sub.2CO.sub.3 and roasting. The present invention also discloses a preparation method of the Bi.sub.2O.sub.3/(BiO).sub.2CO.sub.3/Bi.sub.2MoO.sub.6 composite photocatalyst which is specifically implemented by the following steps: step 1: preparing a Bi.sub.2MoO.sub.6 photocatalyst; step 2: introducing Bi.sub.2O.sub.3 and (BiO).sub.2CO.sub.3 nanosheets to a surface of the Bi.sub.2MoO.sub.6 photocatalyst obtained in step 1 through addition of Na.sub.2CO.sub.3 and roasting to obtain the Bi.sub.2O.sub.3/(BiO).sub.2CO.sub.3/Bi.sub.2MoO.sub.6 composite photocatalyst. The photocatalyst of the present invention has no agglomeration, a wide responsive range of visible light, a significantly improved catalytic activity compared with a Bi.sub.2MoO.sub.6 alone, and excellent reusability. Moreover, the preparation method is simple with mild conditions, desired controllability and convenient operation.

Crystalline α-Fe.sub.2O.sub.3 nanoparticles prepared by ultrasonic treatment of a solution of an iron (III)-containing precursor and an extract from the seeds of a plant in the family Linaceae. The crystalline α-Fe.sub.2O.sub.3 nanoparticles have a spherical morphology with a diameter of 100 nm to 300 nm, a mean surface area of 240 to 260 m.sup.2/g, and a type-II nitrogen adsorption-desorption BET isotherm with a H3 hysteresis loop. The crystalline α-Fe.sub.2O.sub.3 nanoparticles have a band gap of 2.10 to 2.16 eV and a mean pore size of 7.25 to 9.25 nm. A method for the photocatalytic decomposition of organic pollutants using the crystalline α-Fe.sub.2O.sub.3 nanoparticles. An antibacterial composition containing the crystalline α-Fe.sub.2O.sub.3 nanoparticles.

The application belongs to the field of material preparation and environments, and specifically, to a precious metal loaded Covalent Organic Framework (COF) composite material and a preparation method therefor. The components of the composite material include precious metal nanoparticles and TpMA. The preparation method includes first mixing the TpMA, chloroauric acid and methanol; and then adding sodium borohydride for reaction, so as to obtain the composite material. The precious metal nanoparticle loaded COF material prepared in the application may be used as a catalyst, which is a novel heterogeneous catalyst with simple, green and efficient preparation; and the material is high in catalytic activity, fast in degradation rate and short in time, and may catalyze the reduction of high concentration pollutants.

The present disclosure belongs to the technical field of sewage treatment, and relates to a preparation method and use of a cobalt nanoparticle/boron nitride composite. The preparation method includes the following steps: dissolving 2-methylimidazole and boric acid in deionized water, and stirring to obtain a solution A; dissolving Co(NO.sub.3).sub.2.Math.6H.sub.2O and Zn(NO).sub.3.Math.6H.sub.2O in deionized water, and conducting ultrasonic dispersion to obtain a solution B; transferring the solution B into the solution A, and stirring to form a clear and transparent solution; transferring the clear and transparent solution into a container lined with Teflon, and conducting a reaction; subjecting an obtained product to cooling, filtration, washing, and drying sequentially to obtain a precursor of the composite; and conducting roasting on the precursor in an ammonia gas atmosphere to obtain the cobalt nanoparticle/boron nitride composite with a spherical superstructure.

Disclosed is an application of a hydrophobic phthalocyanine as a heterogeneous catalyst in oxidizing phenol wastewater by hydrogen peroxide. A hydrophobic silane is decorated on a bacterial cellulose-metal phthalocyanine heterogeneous catalyst to obtain a hydrophobic phthalocyanine heterogeneous catalyst; during the catalytic degradation of phenols, the obtained catalyst is capable of adjusting a concentration of hydrogen peroxide oxidant around the catalyst. A preparation method of the hydrophobic phthalocyanine comprises: 1. preparing a mixed solution of a bacterial cellulose medium containing metal phthalocyanine; 2. adding acetic acid bacterium into the mixed solution obtained in step 1 for biological culture; 3. heating the product obtained in step 2, and taking out a solid for cleaning and drying; 4. preparing a hydrophobic silane solution; and 5. immersing the product obtained in step 3 into the solution obtained in step 4, and taking out a solid after reaction for cleaning and drying.

The present invention relates to a method for reducing the amount of organic compounds in wastewater, comprising providing a wastewater comprising NaCl in a concentration of at least 6% (w/v), contacting said hypersaline wastewater with a halophilic microorganism, and reducing the 5 amount of organic compounds by said halophilic microorganism in the presence of at least one substrate which has been added to the wastewater and which allows for the growth of said halophilic microorganism, wherein the reduction of the amount of organic components is carried out as a continuous process in bioreactor.

Methods to remediate a contaminated material are provided. In one embodiment, a biocatalyst that digests hydrocarbon contaminants is activated with a nutrient and the activated biocatalyst is combined with the contaminated material and water to form a mixture. The mixture is incubated for a period of time, and the level of contaminant in the mixture is determined to ascertain whether to incubate further, add additional biocatalyst mix, or provide the remediated material for further processing. In one embodiment, the remediated material is provided for reuse or recycling with a second material, such as a construction aggregate. The method is particularly suited for remediation of drill cuttings, mine tailings, hydrocarbon-contaminated soil, and the like.

The invention provides a process for the preparation of bismuth oxyhalide, comprising a precipitation of bismuth oxyhalide in an acidic aqueous medium in the presence of a reducing agent. Also provided are bismuth oxyhalide compounds doped with elemental bismuth Bi.sup.(0). The use of Bi.sup.(0)doped-bismuth oxyhalide as photocatalysts in water purification is also described.