Disclosed in the present disclosure are a method and system for producing hexafluoro-1,3-butadiene. It includes: under the action of a catalyst, chlorotrifluoroethylene reacting with hydrogen gas in a first reactor to obtain a mixture, the mixture entering a rectification apparatus, trifluoroethylene obtained by rectification entering a second reactor and reacting with bromine under light to obtain 1,2-dibromo-trifluoroethane; in a third reactor pre-loaded with the 1,2-dibromo-trifluoroethane, adding the 1,2-dibromo-trifluoroethane and solid alkali, and performing reaction to obtain bromotrifluoroethylene; and adding the bromotrifluoroethylene to a fourth reactor holding with zinc powder, an initiator and an organic solvent for reaction, so as to obtain a trifluoroethenyl zinc bromide solution, performing filtration, and then adding a coupling agent for a coupling reaction, so as to obtain hexafluoro-1,3-butadiene. The present disclosure has the advantages of high safety, good in catalytic stability and high in process selectivity, and can achieve continuous production.

The invention relates to a method for the preparation of a hybrid nano-structured composite comprising cellulose nano-particles and metal compound nano-particles, to the nano structured-composite product obtainable by the process and to uses thereof. The method comprises the steps of contacting virgin cellulose with a molten metal salt solvent M.sub.1-S and dissoluting the virgin cellulose, optionally exchanging at least part of metal ions M.sub.1 with metal ions M.sub.2 and converting at least part of the metal ions M.sub.1 and/or optional M.sub.2 to metal compound nano-particles, precipitating the cellulose nano-particles and isolating the co-precipitated cellulose- and metal compound nano-particles.

The invention relates to a method for the preparation of a hybrid nano-structured composite comprising cellulose nano-particles and metal compound nano-particles, to the nano structured-composite product obtainable by the process and to uses thereof. The method comprises the steps of contacting virgin cellulose with a molten metal salt solvent M.sub.1-S and dissoluting the virgin cellulose, optionally exchanging at least part of metal ions M.sub.1 with metal ions M.sub.2 and converting at least part of the metal ions M.sub.1 and/or optional M.sub.2 to metal compound nano-particles, precipitating the cellulose nano-particles and isolating the co-precipitated cellulose- and metal compound nano-particles.

The present disclosure discloses a method of promoting rice growth using artificial humic acid synthesized by catalysis of nanoscale Ferric oxide, belonging to the field of nanoscale agriculture. The present disclosure discloses a method for synthesizing artificial humic acid from waste biomass with catalysis of transition metal, including the following steps: adding a mixed solution of an alkali, a transition metal catalyst and water into a biomass raw material, and carrying out catalytic reaction at 160-250? C. for 6-48 hours. The artificial humic acid can accelerate germination of rice, effectively promote growth of the rice (the root activity is improved by 166.76% and the net photosynthetic rate is improved by 72.08%), improve the absorption of water and nutrients and the transport of nutrients by rice roots and improve the ability of rice to resist oxidative stress and salt stress.

The present disclosure discloses a method of promoting rice growth using artificial humic acid synthesized by catalysis of nanoscale Ferric oxide, belonging to the field of nanoscale agriculture. The present disclosure discloses a method for synthesizing artificial humic acid from waste biomass with catalysis of transition metal, including the following steps: adding a mixed solution of an alkali, a transition metal catalyst and water into a biomass raw material, and carrying out catalytic reaction at 160-250? C. for 6-48 hours. The artificial humic acid can accelerate germination of rice, effectively promote growth of the rice (the root activity is improved by 166.76% and the net photosynthetic rate is improved by 72.08%), improve the absorption of water and nutrients and the transport of nutrients by rice roots and improve the ability of rice to resist oxidative stress and salt stress.

A method of synthesizing an Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite, the method comprising: loading tungsten oxide (WO.sub.3) powder in a fluidized bed reactor followed by H.sub.2 treatment to produce reduced tungsten oxide (WO.sub.3) nanoparticles or WO.sub.3-x nanoparticles; producing reduced titanium dioxide (TiO.sub.2) nanoparticles or TiO.sub.2-y (containing defect states) nanoparticles in-situ; coupling the TiO.sub.2-y nanoparticles with the WO.sub.3-x nanoparticles to provide a titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x); and simultaneous substitutional doping of TiO.sub.2-y and WO.sub.3-x in the titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x) with gold ions (Au) to obtain the Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite; wherein x has a value between 0.33 and 0.37. The thus produced composite can be used as a photocatalyst.

A method of synthesizing an Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite, the method comprising: loading tungsten oxide (WO.sub.3) powder in a fluidized bed reactor followed by H.sub.2 treatment to produce reduced tungsten oxide (WO.sub.3) nanoparticles or WO.sub.3-x nanoparticles; producing reduced titanium dioxide (TiO.sub.2) nanoparticles or TiO.sub.2-y (containing defect states) nanoparticles in-situ; coupling the TiO.sub.2-y nanoparticles with the WO.sub.3-x nanoparticles to provide a titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x); and simultaneous substitutional doping of TiO.sub.2-y and WO.sub.3-x in the titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x) with gold ions (Au) to obtain the Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite; wherein x has a value between 0.33 and 0.37. The thus produced composite can be used as a photocatalyst.

A catalyst for production of carboxylic acid ester, containing: catalyst metal particles; and a support supporting the catalyst metal particles, wherein a bulk density of the catalyst for production of carboxylic acid ester is 0.50 g/cm.sup.3 or more and 1.50 g/cm.sup.3 or less, when a particle diameter, at which a cumulative frequency is x % in a particle diameter distribution based on a volume of the catalyst for production of carboxylic acid ester, is defined as D.sub.x, D.sub.10/D.sub.50?0.2 and D.sub.90/D.sub.50?2.5 are satisfied, and when a half-width of the particle diameter distribution is defined as W, W/D.sub.50?1.5 is satisfied.

A catalyst for production of carboxylic acid ester, containing: catalyst metal particles; and a support supporting the catalyst metal particles, wherein a bulk density of the catalyst for production of carboxylic acid ester is 0.50 g/cm.sup.3 or more and 1.50 g/cm.sup.3 or less, when a particle diameter, at which a cumulative frequency is x % in a particle diameter distribution based on a volume of the catalyst for production of carboxylic acid ester, is defined as D.sub.x, D.sub.10/D.sub.50?0.2 and D.sub.90/D.sub.50?2.5 are satisfied, and when a half-width of the particle diameter distribution is defined as W, W/D.sub.50?1.5 is satisfied.

The present invention relates to photocatalytic materials for use in the conversion of CO.sub.2 to non-CO.sub.2 carbon containing products. The photocatalytic materials comprise a metal nanofiber and a carbon-based nanostructure bound to the surface of the metal nanofiber. Methods for preparing such materials are described, as well as their use in the conversion of CO.sub.2 to non-CO.sub.2 carbon containing products. For example, the photocatalytic materials of the invention may be used to convert CO.sub.2 to methanol and/or ethanol with high conversion rates.