67 results about "Compounds of lead" patented technology

A process for recovering lead oxides from the spent paste of exhausted lead acid batteries. The process provides heating the spent paste with an alkali hydroxide solution at elevated temperatures prior to calcinations. Calcination is at various temperatures so that either lead mono-oxide, lead dioxide or red lead is obtained as the principal product. There is also provided the use of the lead oxide to prepare the paste for positive and negative electrodes or other lead compounds.

The invention discloses a lead compound nano-powder preparation method for recovery and manufacture of lead-acid battery. The lead compound nano-powder preparation method comprises the following steps that 1, lead, a lead salt or waste lead-acid battery lead paste reacts with one or more organic or inorganic compounds to produce a soluble lead salt solution or a lead hydroxide solution; 2, one or more alkalis or caustic alkalis are added into the soluble lead salt solution, or a part or excess amount of H2CO3 or CO2, sulfuric acid, one or more organic acids or their salts are added into the lead hydroxide solution, and 3, lead oxide or lead hydroxide precipitates obtained by the step 2 are filtered and are subjected to drying and pyrolysis to form the lead compound nano-powder. The lead compound nano-powder preparation method realizes environmentally friendly recovery and production, has low energy consumption, greatly reduces a production cost, and shortens a production period. The lead compound nano-powder obtained by the lead compound nano-powder preparation method is conducive to improvement of technical product performances.

A process for preparing lead-free glass powder used for electronic paste, which comprises: firstly uniformly mixing silicon dioxide or sodium silicate, barium oxide or barium carbonate, boron oxide or boric acid, bismuth oxide or bismuth sulfate, aluminum oxide, aluminum sulfate or aluminum silicate, zinc oxide or zinc carbonate, sodium oxide, sodium carbonate or sodium bicarbonate, potassium oxide or potassium carbonate and titanium dioxide, then heating the mixed raw materials to melt, cooling the melted mixture, then grinding into power by a ball grinder, sieving by a sieve of 100-400 eye and lastly drying glass powder to obtain the lead-free glass powder. Because the glass power of the invention does not contain lead oxide (PbO) or compounds of lead oxide (PbO), the invention is harmless in the manufacture process of paste, simultaneously is beneficial for environmental protection, and is convenient for recycling and reusing electronic product modules containing the electronic paste.

Polymer fibers having a novel cross-sectional geometry are used as stationary phase materials for liquid chromatography separations. Fibers of 20 to 50 micrometer diameters have surface-channel structures extending their entire lengths. Bundles of fibers having this novel cross-sectional geometry are packed in columns. Different polymer compositions permit the “chemical tuning” of the separation process. Channeled fibers composed of polystyrene and polypropylene have been used to separate mixtures of polyaromatic hydrocarbons (PAHs), Pb-containing compounds and fatty acids. Use of channeled fibers allows a wide range of liquid flow rates with very low backing pressures. Applications in HPLC, cap-LC, prep-scale separations, analytical separations, single fiber separations, waste remediation/immobilization, extraction of selected organic molecules/ions from solution, purification of liquid streams (process waste, drinking water, pure solvents), selective extraction of cell matter and bacteria from growth media, and immobilization of cell matter and bacteria are envisioned.

It is an object of the present invention to provide an anticorrosive coating composition which uses a pollution-free (heavy metal-free) rust preventive pigment and exhibits anticorrosive performances equal or superior to those of lead compounds or chromic acid compounds even if the pigment is blended in various binder resins and also to provide an anticorrosive coating composition having excellent storage stability. The present invention relates to an anticorrosive coating composition comprising a binder resin and a pollution-free (heavy metal-free) rust preventive pigment containing a condensed calcium phosphate produced by baking a single substance or mixture of a calcium component and a phosphorous component in the following atomic ratio (Ca/P=m): 0.50<m<1.00, at 180 to 350° C.

A process for producing high purity lead oxide from impure lead compounds particularly from waste lead battery paste which includes an oxidation-reduction step. The process results in a reduction of impure lead compounds to the +2 valence state and metal particle contaminants are oxidized to the +2 state.

The invention discloses a metal electrolytic method in alkaline solutions, which comprises the following steps: casting deposited lead or deposited zinc or commercially available crude lead or crude zinc to a 0.2-6 cm thick anode plate, and preparing a lamelliform cathode through pure lead, pure zinc or an inert electrode; electrolytic refining in alkaline electrolyte, and finally obtaining high-purity electrolytic lead or electrolytic zinc on the cathode, wherein the metal electrolytic method further comprises: 1) dissolving a lead compound or a zinc compound into the alkaline electrolyte, and adding a reducing agent to reduce lead dioxide existing in the lead compound or the zinc compound to a soluble lead complex; and 2) selecting the lamelliform cathode prepared by the pure lead, pure zinc or inert electrode in the electrolysis process, selecting the anode as iron with purity larger than 94%, and finally obtaining the deposited lead or deposited zinc on the cathode. According to the metal electrolytic method disclosed by the invention, the lead compound or the zinc compound is dissolved under an alkaline condition through a complexing agent, the electrolytic lead or electrolytic zinc is obtained by electrolyzing the cathode, and a byproduct ferric oxide or ferric hydroxide is obtained by separation.

The invention discloses a preparation method of PbS quantum dots. The preparation method comprises the following steps of (1) mixing a halogen compound of lead with oleylamine to form a mixture, heating the mixture to 80-150 DEG C in an inert atmosphere, and carrying out heat preservation to obtain an oleylamine solution of lead halide; and (2) injecting a ZnS nano-rod solution prepared in advance into the oleylamine solution of the lead halide, and reacting at a temperature of 80-190 DEG C to obtain a reaction product comprising the PbS quantum dots. Through modification of the critical preparation method principle and the reaction conditions of various steps, compared with the prior art, the preparation method has the advantages that the problems that the preparation method of the PbS quantum dots is complicated and high in cost can be effectively solved, and prepared nanoparticles have the characteristics of high crystallinity, size uniformity and stability and good optical characteristics and are very beneficial to development of various characteristics of the PbS quantum dots.

The present invention aims to provide a piezoelectric composition which is free of lead based compounds and is represented by the following formula (1), (Bi<0.5x>Na<0.5x>Ba<0.7y+z>Ca<0.3y>) (Ti<x+y+0.8z>Hf<0.2z>) O<3> (1), wherein, x, y, z and a in formula (1) meets the following conditions, 0.70<=x<=0.90, 0.02<=y<=0.28, 0.02<=z<=0.28, 0.90<=a<=1.10 and x+y+z=1.

An object of the present invention is to provide an electroless displacement gold plating solution, an additive for use in preparing the plating solution, and a metal composite material obtained by treatment with the plating solution. The present invention provides an electroless displacement gold plating solution containing a water-soluble gold compound, a complexing agent, and a water-soluble silver compound, and optionally a water-soluble thallium compound, a water-soluble lead compound, a water-soluble copper compound or a water-soluble nickel compound, or any combination thereof. The plating solution has good stability and, even not only immediately after the preparation but also after a lapse of a certain time period from the preparation, can be used for production of a metal composite material exhibiting a even plated appearance and also having a thick gold coating film.

The invention belongs to a wet metallurgy process, and relates to a process for reducing a lead compound as metal lead in ammonium sulfate water solution. Ammonium sulfate water solution is used as electrolyte; the lead compound is used as a raw material; titanium is used as an anode; stainless steel or lead is used as a cathode; a direct-current electric field is applied in an electrolytic cell; the lead compound obtains electrons at the cathode to reduce as the metal lead; ammonia is oxidized as nitrogen for emission at the anode, and meanwhile, H+ ions are generated; sulfates and chlorine ions in the compound enter the solution to generate ammonium sulfate and ammonium chloride with added ammonia water; lead monoxide and lead dioxide in the lead compound are reduced as the metal lead; and meanwhile, H+ ion combination generation water generated by OH+ and the anode is released. The lead compound includes such materials as lead sulfate, lead monoxide, lead dioxide, lead chloride and mixtures thereof as waste lead accumulator paste. The process is different from traditional electrolysis and electrodeposition process; electrolyte contains no lead; and the lead compound is directly reduced as the metal lead at the cathode.

The invention relates to a preparation method of a carbon-based composite material for a cathode of a lead-carbon battery, which can prepare a carbon-based lead compound composite material with a controllable proportion, wherein the lead compound uniformly distributes on the surface of carbon material and maintains the original structure character of the carbon material. The preparation method isas follows: the carbon material and a lead ion solution are uniformly mixed in a reaction vessel, a precipitant is slowly dropped, the lead ions are completely deposited on the surface of the carbon material, then filtered, washed and dried to obtain a precursor, and the composite material is obtained through high temperature treatment, and mass ratio of lead compounds is between 1% to 90%. The composite material and the active substances of cathode of lead-acid battery can be better combined by the lead oxide particles on the surface, while the cathode capacity of the cathode of the battery prepared by using the composite material additive is obviously increased, the hydrogen evolution of the cathode is reduced, cathode active material utilization rate is also greatly improved, and the cycle life of high-rate charge-discharge of partial charge state of the cathode is significantly prolonged.

A novel method for improving the coating film smoothness and a cationic electrodeposition coating composition containing no heavy metal-based rust prevention agents such as lead compounds and capable of forming a coating film with a high corrosion resistance are provided. A coating composition forming a coating film under heating, which comprises, relative to a resin solid matter, 0.5 to 20% by weight of a compound having an N-substituted benzoxazine ring represented by the following general formula (1): in the formula, R is a hydrocarbon group having 1 to 8 carbon atoms.

This invention relates to a crystal glass having a refractive index higher than 1.53 and a high mechanical strength, free of any content of compounds of lead, barium and arsenic and guaranteeing maximum safety for health, which consists in that it comprises by weight: 55-70% SiO₂, 0.05-3.5% Li₂O, 2-15% Na₂O, more than 3% and less than 5% or more than 15% and less than 19% K₂O, 5 to 10% CaO, more than 1% and less than 4% or more than 7% and less than 8% ZnO, 0.1-3.5% B₂O₃, 0.1-3.5% Al₂O₃, 0.1-3.5% TiO₂, less than 3.5% ZrO₂, 0.05-1.5% Gd₂O,₃ 0.05-1% P₂O₅, 0.1-1% Sb₂O₃,

A piezoelectric ceramic compact is provided as an effective material for forming piezoelectric ceramic devices and the like, and is primarily composed SrBi2Nb2O9 containing no lead nor lead compounds or containing a little amount thereof, and has a maximum value Qmax improved to a level suitable for practical use. In the piezoelectric ceramic compact primarily having a bismuth-based layered compound containing Sr, Bi, Nb and oxygen, when the molar ratio of Sr, Bi and Nb contained as primary components in the bismuth-based layered compound is represented by a: b: c, the relationships represented by 0.275<=a/c<0.5 and 4<=(2a +3b)/c<=4.5 are satisfied.

Wet process of low environmental impact recovers the lead content of an electrode slime and/or of lead minerals in the valuable form of high purity-lead carbonates that are convertible to highly pure lead oxide by heat treatment in oven at relatively low temperature, perfectly suited for making active electrode pastes of new batteries or other uses. The process basically comprises the following steps: a) adding sulphuric acid to a different acid leach suspension of the starting impure material for converting all dissolved lead compounds to insoluble lead sulphate; b) separating the solid phase constituted by lead sulphate and undissolved impurities from the acid leach solution; c) selectively dissolving lead sulphate contained in said separated solid phase in an aqueous solution of a lead solubilizing compound comprising preferably sodium acetate; d) separating the solution containing dissolved lead sulphate from the solid phase residue including undissolved impurities; e) adding to the separated solution of lead sulphate a carbonate of the same cation of said dissolving compound for forming insoluble lead carbonate and/or and lead oxycarbonate and a dissolved sulphate of the same cation; f) separating the precipitated carbonate and/or oxycarbonate of lead from the dissolving solution now containing also sulphate of the cation of said solubilizing compound.

The invention discloses a preparing method for a lead-sulfide nanocrystalline material. The preparing method for the lead-sulfide nanocrystalline material is characterized by including the following steps that a lead compound and sodium dimethyldithiocarbamate are added into pure water and stirred and then subjected to ultrasonic for 30 min to 40 min, suction filtration, washing and drying are carried out, and a lead-source precursor is obtained; the lead-source precursor is added into an organic solvent, the mixture is fully stirred and mixed and subjected to ultrasonic washing for 20 min to30 min, and precursor reaction liquid is obtained; under the ultrasonic stirring power of 100 W to 400 W, the precursor reaction liquid is subjected to gradient microwave heating, wherein gradient microwave heating is heated to be 110 DEG C to 120 DEG C, first reaction liquid is obtained, and the heating temperature gradient is 35 DEG C/min to 40 DEG C/min; the heating temperature is 130 DEG C to180 DEG C, heat preservation is carried out for 4 min to 6 min, second reaction liquid is obtained, and the heating temperature gradient is 2 DEG C/min to 30 DEG C/min; the second reaction liquid is naturally cooled to the room temperature, centrifuged, precipitated and washed, and the lead-sulfide nanocrystalline material is obtained.