Abstract: Provided are a water-soluble Pd(II) complex, a synthesis method thereof and use thereof as a catalytic precursor. The complex has a chemical name, ammonium dinitrooxalato palladium (II), and a molecular formula of (NH4)2[Pd(NO2)2(C2O4)]·nH2O (n is the number of crystal water). The Pd(II) complex is synthesized by using PdCl2 or [Pd(NH3)2Cl2] as a starting material which is firstly converted into [Pd(NH3)4]Cl2 in ammonium hydroxide, followed by a chemical reaction between [Pd(NH3)4]Cl2 and excessive NaNO2 to produce trans-[Pd(NH3)2(NO2)2] via ligand substitution mechanism, and finally dissolving trans-[Pd(NH3)2(NO2)2] in an aqueous solution of oxalic acid leads to the formation of the target product (NH4)2[Pd(NO2)2(C2O4)]·2H2O. The complex does not contain chlorine and other elements that are harmful to a catalyst, is readily soluble in water and has a low thermal decomposition temperature.

Abstract: A method for comprehensively processing noble lead provided and utilizes two instances of vacuum distillation to realize an open circuit of arsenic, lead, antimony and bismuth and the high-efficiency enrichment of precious metals of gold and silver, and can obtain elemental arsenic, a lead-bismuth-antimony alloy, a silver alloy and a copper alloy, respectively. The lead-bismuth-antimony alloy, the silver alloy and the copper alloy are processed by oxidation refining, electrorefining and chlorination refining to obtain refined lead, refined antimony, antimony trioxide, electrolytic silver and electrolytic copper, and to realize gold enrichment. The entire process has advantages of high metal direct yield, low energy consumption, short flow chart, simple equipment, etc., and vacuum distillation belongs to a physical process in which the alloy can be separated only by means of the difference in saturated vapor pressure between the metals, without generation of wastewater, waste gas and waste residue.

Abstract: A method for producing stannous sulfide, the method including: 1) heating a tin-containing material to 200-600° C., and mixing sulfur with the tin-containing material heated, to yield a product; and 2) distilling the product in a vacuum furnace at a pressure of 1-500 pascal.

Abstract: A method for comprehensively processing noble lead provided and utilizes two instances of vacuum distillation to realize an open circuit of arsenic, lead, antimony and bismuth and the high-efficiency enrichment of precious metals of gold and silver, and can obtain elemental arsenic, a lead-bismuth-antimony alloy, a silver alloy and a copper alloy, respectively. The lead-bismuth-antimony alloy, the silver alloy and the copper alloy are processed by oxidation refining, electrorefining and chlorination refining to obtain refined lead, refined antimony, antimony trioxide, electrolytic silver and electrolytic copper, and to realize gold enrichment. The entire process has advantages of high metal direct yield, low energy consumption, short flow chart, simple equipment, etc., and vacuum distillation belongs to a physical process in which the alloy can be separated only by means of the difference in saturated vapor pressure between the metals, without generation of wastewater, waste gas and waste residue.

Abstract: A method for producing stannous sulfide, the method including: 1) heating a tin-containing material to 200-600° C., and mixing sulfur with the tin-containing material heated, to yield a product; and 2) distilling the product in a vacuum furnace at a pressure of 1-500 pascal.