Abstract: The present invention provides a process for metallurgy and separating a rare earth concentrate using a combination method, the process including: treating the rare earth concentrate containing bastnaesite by using a method including roasting under an atmosphere, leaching with hydrochloric acids, and roasting with a sulfuric acid, wherein stepping acid leaching with low-concentration hydrochloric acids is controlled during the leaching with the hydrochloric acids so as to obtain a rare earth solution with a high concentration (150-250 g/L REO), such that a leaching rate of Ce reaches 60% or more, and the content of F? in a leaching liquor is reduced by aging; and rare earth is further recovered from a leach residue by roasting with the sulfuric acid and leaching with water, and the total yield of the rare earth reaches 95% or more.

Abstract: The present invention relates to a polymer/filler/metal composite fiber, including a polymer fiber comprising a metal short fiber and a filler; the metal short fiber is distributed as a dispersed phase within the polymer fiber and distributed in parallel to the axis of the polymer fiber; the filler is dispersed within the polymer fiber and distributed between the metal short fibers; the filler does not melt at the processing temperature of the polymer; said metal is a low melting point metal and selected from at least one of single component metals and metal alloys, and has a melting point which ranges from 20 to 480° C., and, at the same time, which is lower than the processing temperature of the polymer; the metal short fiber and the polymer fiber have a volume ratio of from 0.01:100 to 20:100; the filler and the polymer have a weight ratio of from 0.1:100 to 30:100.

Abstract: Disclosed herein are a polypropylene with narrow molecular weight distribution and a process for preparing the same in a reactor using a Ziegler-Natta catalyst.

Abstract: Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxide to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate.

Abstract: Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxidee to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate.

Abstract: A polyethylene composition comprising an ethylene/?-olefin copolymerized linear low density polyethylene, wherein the polyethylene composition has a Mw of from 100,000 g/mol to 200,000 g/mol, a Mw/Mn of from 4.0 to 9.0, a Mz/Mw of from 4.0 to 7.0, and a Mz+1/Mw of from 4.5 to 13.5, is provided. A film formed of the polyethylene composition is also provided.

Abstract: A method for comprehensively recovering rare earth elements and fluorine element in a bastnaesite treatment process. The method comprises: oxidation roasting a bastnaesite, and leaching a roasted mixture using a hydrochloric acid, adding a roasting promoter to the bastnaesite during the roasting process; and/or during the leaching process using the hydrochloric acid, adding a catalytic leaching promoter into the mixture, obtaining a rare earth chloride solution containing little cerium element and a cerium-rich residue containing the fluorine element; and separating and recovering rare earth fluorides from the cerium-rich residue.

Abstract: The present invention provides a cerium oxide based composite polishing powder and a preparation method thereof. The polishing powder contains the element magnesium in an amount of 0.005 wt %-5 wt % to magnesium oxide meter. The preparation method includes: (1) uniformly mixing a salt solution containing cerium serving as the main component of the polishing powder; (2) uniformly mixing a precipitating agent of an aqueous magnesium bicarbonate solution with the mixed solution prepared in step (1) to obtain a slurry; (3) aging the slurry prepared in step (2) for 0-48 h while the temperature of the slurry is kept at 30-90 degrees centigrade, and filtering the aged slurry to obtain the precursor powder of the polishing powder; (4) calcinating the precursor powder at 600-1000 degrees centigrade, then dispersing and separating the calcinated precursor powder to obtain the polishing powder. The present invention improves the polishing performance and the suspension performance of polishing powder.

Abstract: The present invention relates to a polymer/filler/metal composite fiber, including a polymer fiber comprising a metal short fiber and a filler; the metal short fiber is distributed as a dispersed phase within the polymer fiber and distributed in parallel to the axis of the polymer fiber; the filler is dispersed within the polymer fiber and distributed between the metal short fibers; the filler does not melt at the processing temperature of the polymer; said metal is a low melting point metal and selected from at least one of single component metals and metal alloys, and has a melting point which ranges from 20 to 480° C., and, at the same time, which is lower than the processing temperature of the polymer; the metal short fiber and the polymer fiber have a volume ratio of from 0.01:100 to 20:100; the filler and the polymer have a weight ratio of from 0.1:100 to 30:100.

Abstract: A polyethylene composition comprising an ethylene/?-olefin copolymerized linear low density polyethylene, wherein the polyethylene composition has a Mw of from 100,000 g/mol to 200,000 g/mol, a Mw/Mn of from 4.0 to 9.0, a Mz/Mw of from 4.0 to 7.0, and a Mz+1/Mw of from 4.5 to 13.5, is provided. A film formed of the polyethylene composition is also provided.

Abstract: A method for comprehensively recovering rare earth elements and fluorine element in a bastnaesite treatment process. The method comprises: oxidation roasting a bastnaesite, and leaching a roasted mixture using a hydrochloric acid, adding a roasting promoter to the bastnaesite during the roasting process; and/or during the leaching process using the hydrochloric acid, adding a catalytic leaching promoter into the mixture, obtaining a rare earth chloride solution containing little cerium element and a cerium-rich residue containing the fluorine element; and separating and recovering rare earth fluorides from the cerium-rich residue.

Abstract: The present invention provides a cerium oxide based composite polishing powder and a preparation method thereof. The polishing powder contains the element magnesium in an amount of 0.005 wt %-5 wt % to magnesium oxide meter. The preparation method includes: (1) uniformly mixing a salt solution containing cerium serving as the main component of the polishing powder; (2) uniformly mixing a precipitating agent of an aqueous magnesium bicarbonate solution with the mixed solution prepared in step (1) to obtain a slurry; (3) aging the slurry prepared in step (2) for 0-48 h while the temperature of the slurry is kept at 30-90 degrees centigrade, and filtering the aged slurry to obtain the precursor powder of the polishing powder; (4) calcinating the precursor powder at 600-1000 degrees centigrade, then dispersing and separating the calcinated precursor powder to obtain the polishing powder. The present invention improves the polishing performance and the suspension performance of polishing powder.

Abstract: The application of aqueous solution of magnesium bicarbonate and/or calcium bicarbonate in the process of extraction separation and purification of metals is disclosed, wherein the aqueous solution of magnesium bicarbonate and/or calcium bicarbonate is used as an acidity balancing agent, in order to adjust the balancing pH value of the extraction separation process which uses an acidic organic extractant, improve the extraction capacity of organic phase, and increase the concentration of metal ions in the loaded organic phase.

Abstract: Disclosed herein are a polypropylene with narrow molecular weight distribution and a process for preparing the same in a reactor using a Ziegler-Natta catalyst.

Abstract: The application of aqueous solution of magnesium bicarbonate and/or calcium bicarbonate in the process of extraction separation and purification of metals is disclosed, wherein the aqueous solution of magnesium bicarbonate and/or calcium bicarbonate is used as an acidity balancing agent, in order to adjust the balancing pH value of the extraction separation process which uses an acidic organic extractant, improve the extraction capacity of organic phase, and increase the concentration of metal ions in the loaded organic phase.

Abstract: The present invention provides a propylene polymer composition for producing a biaxially oriented film, comprising propylene random copolymer and propylene homopolymer; wherein the propylene random copolymer is a copolymer of propylene and ethylene, optionally comprising one or more alpha-olefins of C4-C10; the propylene polymer composition has an overall isotacticity index, as determined by nuclear magnetic resonance method, of greater than or equal to 96.5%, and an ethylene content of greater than 0.3 wt %; and wherein, the melt flow rate of the propylene random copolymer is lower than that of the propylene homopolymer. The biaxially oriented polypropylene film produced by the propylene polymer composition of the present invention exhibits excellent physical properties, and has, in the absence of any stiffening agent, relatively higher modulus and stiffness.

Abstract: The present invention provides a propylene polymer composition for producing a biaxially oriented film, comprising propylene random copolymer and propylene homopolymer; wherein the propylene random copolymer is a copolymer of propylene and ethylene, optionally comprising one or more alpha-olefins of C4-C10; the propylene polymer composition has an overall isotacticity index, as determined by nuclear magnetic resonance method, of greater than or equal to 96.5%, and an ethylene content of greater than 0.3 wt %; and wherein, the melt flow rate of the propylene random copolymer is lower than that of the propylene homopolymer. The biaxially oriented polypropylene film produced by the propylene polymer composition of the present invention exhibits excellent physical properties, and has, in the absence of any stiffening agent, relatively higher modulus and stiffness.