Method of quantitative determination of content of lithium in alloy |
|
IPC classes for russian patent Method of quantitative determination of content of lithium in alloy (RU 2288289):
    
Method of assay determination of content of gold in ores and in products of their processing / 2288288
Proposed method includes melting of starting material with lead oxide, soda, borax and flour for obtaining lead alloy (crude lead), its cupellation till gold-silver regulus, dissolving of silver in diluted nitric acid and determination of amount of gold by weighing or by any other instrumental method. Melting process is carried out in metal crucibles at temperature of 600-800°C for 10-30 minutes; charge per 10 g of sample contains the following components: 20-50 g of sodium or potassium hydroxide; 2-20 g of borax; 1-10 g of soda; 15-30 g of litharge and 1-3 g of flour. Method is recommended for assay of samples having mass of 10-100 g.
Method of determination of content of palladium and platinum in ores / 2283356
Proposed method includes decomposition of ore by hydrofluoric and nitric acids followed by further decomposition by aqua regia, boiling-off to moist salts, dissolving of them in hydrochloric acid and extraction. Determination of content of palladium is carried out in organic phase thus obtained and that of platinum is carried out in hydrochloric acid phase. Extractants used for such determination are s-alkylisothiouronium halides and alcohols of C5-C8 fractions, as well as kerosene, benzene, toluene and xylols used as diluents. Used as s-alkylisothiouronium halides are chlorides, bromides and iodides from C7 to C14 and their fractions.
 Method of determination of cause of low impact viscosity of low-carbon steels / 2281975
Proposed method consists in finding-out dependence of grain size of microstructure and presence of ferrite net, as wells as marks on bearing faces of tested specimens for products of the same type made from steel of definite quality during analysis of causes of low impact viscosity recommended standards are established for these parameters and dependences thus found are compared with the data of specimens of low (below standard norm) impact viscosity and these data are estimated for compliance with the recommended standards. Dependences thus found are used repeatedly and constantly.
 Method of a quality control over the test crucible melting / 2272850
The invention is pertaining to nonferrous metallurgy, in particular, to the methods of detection of the noble metals in the mineral raw materials. The technical result of the invention is an increased trustworthiness to the results of the testing crucible melt analysis. The method is conducted in the following way. From the material of the laboratory test sample take out the analytical part of the filler, mix it with the calculated amount of the charge and the mixture is smelt according to the standard method. During the smelt visually control the height of the boiling layer of the melt slag and lead. On completion of the smelt measure the mass of the slag and lead and calculate an admissible height of the boiling layer of the melt according to the following formula:0,9·Hm≥Hc≥[1,9/tg2α/2·(Mш/ρш+Mc/ρc)]1/3, whereHcr - depth of the crucible in meters(m);Hsl - the height of the boiling gas-slag layer, m; α - an angle at the apex of the cone of the inner surface of the crucible, in degrees;Msl, Mla - masses of the slag and mass of the lead alloy accordingly, kg;ρsl, ρla - density of the slag and density of the lead accordingly, kg/m3. If the visual estimation of the height of the boiling layer of the melt exceeds the limits of admissible values, them one may draw a conclusion about the low quality of the testing smelt, make corrections in the composition of the charge and repeat the test analysis.
 Method of preparing samples for analysis / 2267111
Method comprises sampling initial material, producing and analyzing group samples before assessing representative mass of analytical samples, estimating representative mass of analytical samples, and calculating the value of the coefficient that characterizes the type of gold-bearing material from the formula proposed.
 Method for determining hardness limit of austenite class steel / 2265213
Method includes subjecting samples of steel to preliminary plastic deformation and on basis of wear test results of pre-deformed samples, graph of change of hardness limit of σ-1 samples is built dependent on their level of pre-deformation. Weighed samples are made with same deformation level and value of magnetic tear force Pmag is determined for each weighed sample. Graph of change of magnetic tear force Pmag is built for samples on basis of their pre-deformation level, graph with adjusting curve in coordinates Pmag - σ-1, setting a connection between Pmag and σ-1 dependent on level of pre-deformation. Hardness limit of σ-1 samples is determined by adjusting curve in coordinates Pmag - σ-1.
 Method of measuring duration of serviceability of metals / 2261436
Method can be used for estimation of deformation-strength properties due to applying load as well as for determining damages by means of X-ray diffraction analysis. Values of structural-sensitive parameter of crystal lattice of tested material are determined by X-ray diffraction analysis in initial and post-deformation states. Deformation-strength characteristics of metal are determined by calculation from changes in structural-sensitive parameter. Serviceability is judged by comparing really achieved characteristics with admissible ones. Width of X-ray line β is used as structural-sensitive parameters. Strength of deformation P, deformation Δl provided by the deformation and corresponding values of structural-sensitive parameter β are registered during testing. Dependence of true stresses S and structural-sensitive parameter β on degree of relative residual deformation δ are calculated on the basis of P and Δl. Destruction diagram (S-δ½) and linearized diagram (β½-δ½) are built to show inflection points. Deformation-strength characteristics SD and δD corresponding to inflection point at destruction diagram (destruction point D) is taken as criterion of admissible surface strength which provides maximal serviceability of metal. Factor of merit η and factor of destruction Δ can be also taken as criteria of serviceability of metal.
 Mode of testing railway rails on contact weariness / 2253112
Contact weariness is induced by high-frequency dynamic components of interaction of wheels and rails, which become apparent at moving at high speed. The mode of testing railway rails on contact weariness is in that tested samples of rail steel are rolled by pinch rolls in longitudinal direction until appearance on the surface of the sample of dents and also deep indents. As samples test rails are used. The diameter of a pinch roll is chosen under condition of equality of reduction ratio of linear size of the site of contact of the pinch roll with the rail along the axis of the last in comparison with corresponding size responsible to conditions of exploitation and speed reduction ratio of rolling motion of the pinch roll along exploited rail.
Material for production of assay stone / 2248336
Assay stone is made from oxide ceramic comprising BeO-TiO2. Material affords the ability to obtain assay stone of regular geometric form with surface, electrical and mechanical properties meeting the requirement for material used in assaying control. Claimed material in useful in standard determination followed by electrochemical recovery of precision metals from solution after assaying control.
 How kopaliani lead alloys containing gold and silver, assay analysis / 2237734
The invention relates to the field of analytical chemistry and can be used in the assay analysis for separating precious metals from lead
 Lithium gamma-aluminate, method of preparation thereof, and lithium preparation method / 2274605
Invention relates to preparing novel inorganic compound, in particular lithium γ-aluminate Li1+xAl1-xO2-x, where 0.01 ≤ x ≤ 0.75, which can be used as dielectric material in production chemical power sources, lithium, etc. as well as to lithium production process using proposed lithium γ-aluminate. Lithium carbonate and aluminum hydroxide are taken at molar ratio (33.8-77.8):(22.2-66.2), thoroughly mixed, and resulting mixture is placed into platinum crucible and gradually heated in furnace under air atmosphere to 500-1100°C using intermediate grinding and ageing for 3 h after each 50°C temperature raise. Based on X-ray structure-measured and chemical composition data, single-phase lithium γ-aluminate Li1+xAl1-xO2-x, where 0.01 ≤ x ≤ 0.75, with tetragonal structure is obtained. Lithium preparation comprises mixing resulting lithium γ-aluminate with aluminum powder at weight ratio (65-70):(30-35), respectively, powering mixture into crucible, placing the latter into vacuum oven, which is evacuated to 0.7-0.8 Pa, heated to 700-1200°C at heating rate 45-55°C/min, kept at this temperature for 4-5 h. and cooled. Thus obtained solid lithium condensate is then melted and powered out into metal receiver.
 Method of refining lithium and installation for its implementation / 2236476
The invention relates to the field of metallurgy and can be used to produce lithium metal of high purity
 Method of extracting lithium from a fluorine-containing concentrates / 2226561
The invention relates to the field of metallurgy, namely the recovery of lithium compounds from fluorinated mica concentrates
 Method for processing concentrates spodumene / 2222622
The invention relates to the processing of concentrates spodumene
 The method of extracting lithium from lepidolite concentrate / 2221886
The invention relates to the processing of concentrates lepidolite
 The method of obtaining lithium and device for its implementation (options) / 2205240
The invention relates to metallurgy and concerns a method for obtaining lithium and device for its implementation
 Method of refining lithium and installation for its implementation / 2187569
The invention relates to the field of metallurgy and can be used to produce lithium metal of high purity
 A method of obtaining a lithium and a device for its implementation / 2149911
The invention relates to metallurgy and more precisely relates to a method of receiving lithium and device for its implementation
 Method of refining lithium and installation for its implementation / 2139363
The invention relates to the field of metallurgy, namely refining lithium
 The method of obtaining lithium / 2135615
Lithium gamma-aluminate, method of preparation thereof, and lithium preparation method / 2274605
Invention relates to preparing novel inorganic compound, in particular lithium γ-aluminate Li1+xAl1-xO2-x, where 0.01 ≤ x ≤ 0.75, which can be used as dielectric material in production chemical power sources, lithium, etc. as well as to lithium production process using proposed lithium γ-aluminate. Lithium carbonate and aluminum hydroxide are taken at molar ratio (33.8-77.8):(22.2-66.2), thoroughly mixed, and resulting mixture is placed into platinum crucible and gradually heated in furnace under air atmosphere to 500-1100°C using intermediate grinding and ageing for 3 h after each 50°C temperature raise. Based on X-ray structure-measured and chemical composition data, single-phase lithium γ-aluminate Li1+xAl1-xO2-x, where 0.01 ≤ x ≤ 0.75, with tetragonal structure is obtained. Lithium preparation comprises mixing resulting lithium γ-aluminate with aluminum powder at weight ratio (65-70):(30-35), respectively, powering mixture into crucible, placing the latter into vacuum oven, which is evacuated to 0.7-0.8 Pa, heated to 700-1200°C at heating rate 45-55°C/min, kept at this temperature for 4-5 h. and cooled. Thus obtained solid lithium condensate is then melted and powered out into metal receiver.
|
FIELD: chemistry of lithium and its alloys; analytical methods of determination of content of lithium; quantitative determination of content of lithium in lithium-boron alloy. SUBSTANCE: proposed method includes determination of initial mass of alloy specimen, heating the alloy specimen under test till separation of free lithium; mass of alloy specimen is determined in inert gas atmosphere; alloy specimen is heated to temperature not below sublimation temperature of pure lithium in vacuum at residual pressure not exceeding 1·10-6 atm; degree of rarefaction in closed space where heating is carried out is checked continuously; abrupt change in angle of inclination of branch of graph of change of specimen mass versus time of extraction of free lithium is indicative of complete distillation of free lithium; quantitative determination of content of free lithium is performed taking into account difference in mass of initial specimen of alloy and mass of specimen recorded at moment of attaining complete extraction of free lithium; specimen of alloy is heated in crucible made from inert refractory material; specimen is loaded into evaporating tube made from inert metal and placed in cavity of evaporating-condensing unit of distillation plant; its inner walls are made from quartz glass. Proposed method may be used for determination of free lithium contained in alloy in chemically unbound state. EFFECT: enhanced accuracy of determination; reduction of time required for conducting process. 2 dwg, 1 ex
The present invention relates to the field of chemistry of lithium and its alloys, namely analytical methods determine the lithium content, and can be used for the quantitative determination of free content of lithium in the lithium-born alloy. A known way of extracting lithium from metal-containing substances (patent RF №2016140, IPC 25 3/02, publ. BI 19/94 from 15.07.94 g)includes heating the source materials and extraction of lithium by electrorefining salt melt. The disadvantages of analogue is the inability to extract and identify free, chemically unrelated lithium from the original substance. Known as the closest to the claimed method for determining lithium alloys of (RF application No. 93021382, IPC 22, 26/12, publ. 10.09.96, BI No. 25/96), comprising heating the alloy to the allocation determined free of lithium, at the same time as the original alloy research subject aluminum alloy, and the presence of lithium judged by the selection of the latter in the form of gas bubbles. The disadvantages of this method include the inability to determine the number of free lithium found in the original alloy in chemically unrelated condition, and relatively low accuracy. The aim of the invention is the development of pic is BA separation and quantitative determination of free lithium in the alloy, containing lithium and boron, as in a chemically bound state and the free (mostly Li) condition. A new technical result provided by the invention, is to provide the possibility of determining the number of free lithium in lithium-born alloy in chemically unrelated condition, reducing the duration of the method and improve the accuracy of its determination. These task and a new technical result is ensured by the fact that in the known method for quantitative determination of lithium in the alloy, which includes the determination of the initial sample mass of the alloy, heating the sample of the alloy to the allocation determined free of lithium, in accordance with the proposed method of determining the mass of the alloy is carried out in an atmosphere of inert gas, the process of heating the alloy to a temperature not lower than the temperature of sublimation of pure lithium lead in vacuum at a residual pressure of not more than 1·10-6ATM, control the constancy of the degree of rarefaction of the atmosphere of a closed volume, which produce heat, but rather the achievement of completeness distillation allocated free lithium judged by a sharp change in the angle of the branches of the graph of the dependence of the mass change of a sample of the alloy from the time of checkout free of lithium, quantitative determination of free lithium done is make the difference of mass of the initial sample of the alloy and the mass of the sample, registered at the moment of complete extraction of free lithium, when this is subjected to heat a sample of the alloy, placed in a crucible of refractory inert material, which is loaded into the evaporation tube is made from an inert metal that is installed in the cavity of evaporation-condensation site distillation unit, the inner wall of which is made of quartz glass. The essence of the proposed method is illustrated as follows. Initially prepare the sample lithium-boron alloy (lbs)weigh in Boxing in an inert atmosphere (to avoid contact with the surrounding atmosphere) and determine the initial mass of the sample alloy m0. Further, in order to avoid falling into the sample vapors or other active components of the atmosphere, it is placed first in the crucible of inert refractory material, then in the evaporation tube is made from an inert metal that is installed in the cavity of evaporation-condensation node (IR), the walls of which are made of quartz glass. The last before the experience is pressurized and connected to the vacuum unit. When using the coating of the walls of the IR quartz glass minimizes the chemical interaction with the material studied lithium-boron alloy and ensure the increases high temperature resistance components of the system and the stability conditions in the zone of the distillation process. Figure 1 shows a diagram of the vacuum setup, where: 1 - vacuum pump; 2 - nitrogen trap for trapping impurities pumped gas environment; 3 - measuring element of the vacuum system installation; 4 - IR; 5 - heating stove. At the time of engagement distillation units include heating the IR (4) oven (5) and establish a predetermined degree of vacuum of the order of ˜ no more than 1·10-6ATM (vacuum pump (1)). In the process of distillation control the consistency of maintaining the degree of rarefaction of the atmosphere of the closed volume (measuring element (3)), which produce heat that is necessary for the stable course of the distillation process. The temperature regime during the whole distillation process support at a given level in the temperature range ˜540-600°that is not lower than the temperature of sublimation of pure lithium for 6 hours. Specified time, the mode of maintenance of vacuum and the temperature regime is established experimentally, and provide optimal conditions for separation of free, chemically unrelated lithium from lithium-boron alloy. Temperature selected from the principle of the manifestation of the fact the beginning of the steady evaporation of free lithium (which is observed at temperatures below ˜540° (C) and the exception appears in the distillate component RA is violated matrix (located in a chemically bound between a lithium and boron). The matrix is the basis of lithium-boron alloy, is a chemical compound of lithium and boron in the stoichiometric ratio of the components. The range of temperatures at which begins the destruction of the matrix alloy is in the range from 650°C and above. Mode pressure (specified degree of vacuum of the order of ˜ no more than 1·10-6ATM), as established in the experiment, which in combination with creating inert atmosphere in a controlled volume also helps release it free, chemically unrelated lithium from this alloy and eliminates the possibility of unauthorized interact chemically active vapors of lithium with pairs of moisture, oxygen and other components of the atmosphere. A further rise of the temperature and amount of the degree of vacuum in excess of the stated limit no significant effect on the evaporation process free of lithium. During distillation lithium register the change in mass of a test specimen of the alloy and on the basis of the received data to build a graph of mass change of the sample from the time of the experiment, which is optimally a period of not less than 6 hours. Figure 2 presents a plot of mass change of the sample from the time at which the curves 1 illustrate the failure required the occupational groups in the controlled area for the beginning of the evaporation of free lithium the curves 2 celebrated the optimal solution of lithium, curves 3 - marked the beginning of the destruction of the matrix alloy and the emergence in a controlled environment pure boron and lithium alloy components. In the process of evaporation of free lithium from the alloy specimen, placed in a crucible inside the evaporator tubes, condensation occurs lithium vapor on the walls of the evaporator tube is made from an inert metal, and on the inner walls of the IR, is made of quartz glass. In the cavity of the vacuum system is placed nitrogen trap (2), where delayed impede the process of a precise definition of the desired element impurity gas environment. At the end of the distillation process the alloy specimen is extracted from the cavity to the IR and weighed, to determine the mass of the sample alloy mk, then by mathematical calculations determine the amount of free lithium in the alloy specimen. Unlike the prototype and from the traditional chemical methods selection of free lithium (for example, by chemical means), which have a high duration of the experiment (up to several days), the proposed method allows you to perform all the procedures for 6-7 hours at a high yield defined free lithium and reduce errors by eliminating the possibility of unauthorized chemical interactions compound is investigated alloy impurities environment. Making the determination of free lithium by traditional chemical transformations associated with the errors caused by the occurrence of a competing, unauthorized interactions with components of the alloy. Thus, the use of all conditions and materials of the proposed method for quantitative determination of lithium in the lithium alloy-boron provides the ability to determine the number of free lithium in lithium-born alloy in chemically unrelated condition, reducing the duration of the method and improve the accuracy of its determination. The possibility of industrial implementation of the proposed method is confirmed by the following example of its specific implementation. Example. In laboratory conditions for the implementation of the method tested distillation vacuum unit, which is controlled by automatic devices. Schematic diagram of the setup is presented in figure 1. Pre-weighted sample lbs (in which the content of free lithium in the range 28-35 wt.%) mass m0=0,05-0,15 g placed in a crucible of refractory inert material, which is loaded into the evaporation tube is made from an inert metal, and place it in the cavity of the evaporation-condensation node (IR), the inner wall of which the issue is lnany made of quartz glass. These operations are carried out in a box with inert atmosphere (argon). Then IR (4) block valve, isolating from atmospheric air, attach it using the cut to a vacuum unit (1) and placed in an oven heating (5). Then carry out the evacuation, and include furnace (5) for heating the sample. The distillation process is carried out in a vacuum with a residual pressure of not more than 1·10-6ATM. Control of the vacuum produced by aquametro ionization-thermocouple type VIT-2. Extraction of free lithium is carried out at a temperature of 550°C for 6 hours. The reduction or increase in temperature in the claimed range is produced using meter-regulator grade 2 TRM-1. After proper exposure of the sample at 550°C for 6 hours the IR with the sample in the closed state is transferred into the box with inert atmosphere. Then disassemble the IR, remove the test sample (Wren) and weighed. These measures are carried out in order to obtain statistical data of the experiment upon which to build a plot of mass change of the sample from the time of the experiment. The fact complete extraction revealed free lithium judged by a sharp change in the angle of the branches of the graph of the dependence of the mass change of a sample of the alloy from the retrieval time freely what about the lithium. The results of the measurements are shown in figure 2. Quantitative determination of free lithium exercise taking into account the difference in mass of the initial sample alloy m0and the mass of the sample, recorded at the time of complete extraction of free lithium (Wren) - mk: C=(mk-m0)/100%, where With content free of lithium, g, m0is the mass of the original sample, g, mk- weight of sample after analysis (Wren), , As shown by experimental studies, the use of the proposed method allows a relatively quick and accurate analysis of lithium-boron alloy on the content of free lithium, as well as to ensure the completeness of its release, which is fully consistent with the data obtained by preliminary theoretical calculations. The method of quantitative determination of lithium in the alloy, which includes the determination of the mass of the sample alloy, the heating is to highlight the designated free of lithium, characterized in that the determination of the mass of the sample of the alloy is carried out in an inert atmosphere, the heating process of the lead alloy to a temperature not lower than the temperature of sublimation of pure lithium in vacuum at a residual pressure of not more than 1·10-6ATM, control the constancy of the degree of rarefaction of the atmosphere of the closed volume is, which produce heat, but rather the achievement of completeness distillation allocated free lithium judged by a sharp change in the angle of the branches of the graph of the dependence of the mass change of a sample of the alloy from the time of checkout free of lithium, quantitative determination of free lithium exercise taking into account the difference in mass of the initial sample of the alloy and the mass of the sample, recorded at the time of complete extraction of free lithium, when this is subjected to heat a sample of the alloy, placed in a crucible of refractory inert material, which is loaded into the evaporation tube is made from an inert metal that is installed in the cavity of evaporation-condensation site distillation unit, the inner wall of which is made of quartz glass.
|