CN102590113B - Method for measuring sodium content - Google Patents

Abstract

The embodiment of the invention discloses a method for measuring sodium content, which is used for measuring the sodium content in a fine lithium sample. The method of the embodiment of the invention comprises the steps of: (1) preparing lithium test solution; (2) titration treatment: calculating the taking volume of the lithium test solution when 100mg of lithium is required; and (3) measuring the sodium content in the taking lithium test solution. The fine lithium sample is produced into the lithium test solution, the titration method is adopted to determine the taking volume of the lithium sample when 100mg of lithium is needed, the lithium test solution is taken according to the volume, a flame atomic absorption spectrum method is adopted to determine the sodium content, so a glovebox, a balance argon bottle and other equipment can be effectively prevented from being used, only several routine chemical reagents and glassware are needed to be use, and the method is simple to operate and has less equipment and fund investment.

Description

A kind of assay method of sodium content

Technical field

The present invention relates to chemical field, relate in particular to a kind of assay method of sodium content.

Background technology

The essence lithium is as the energy metal of 21 century, in recent years, obtain fast development, it becomes a kind of rare element that has development potentiality with its distinctive nulcear properties, and due to lithium without fission product, can not cause radiation pollution, be called the important materials that develops sophisticated technology, but due to the existence of impurity elements such as containing potassium in smart lithium, receive, the physicochemical property of smart lithium have been affected, so it is most important to the quality that guarantees product to measure the content of sodium in lithium metal.

In the prior art, the method of measuring sodium content in smart lithium needs the quality of accurate weighing smart lithium sample to be measured, in analyzing smart lithium sodium content the time, because the chemical property of lithium is very active, easily oxidation in air, can't be in air the quality of weighing smart lithium to be measured accurately, traditional method is: first take cleaning, the quality of dry measuring cup, smart lithium sample that clip is appropriate in being full of the glove box of argon gas, be placed in this airtight measuring cup, and then on balance total quality of weighing essence lithium sample and measuring cup, the difference of two quality is the quality of smart lithium sample, sample after finally taking is dissolved in pure water, content with aas determination sodium.

The inventor finds under study for action, in smart lithium sample of the prior art, there is following defect in the assay method of sodium content: the equipment needed is too much, glove box, balance, argon gas etc. are arranged, need weighing twice, process is complicated, and if in glove box argon gas not enough or have oxygen, will cause the surface of smart lithium sample to be oxidized to Lithia, the weighing of essence lithium sample is inaccurate, causes the mensuration of sodium content in smart lithium sample inaccurate.

Summary of the invention

The embodiment of the present invention provides a kind of assay method of sodium content, utilize the HCL standard titration solution to carry out the titration processing to the lithium test solution, the volume of the lithium test solution that need pipette while needing the 100mg lithium by the HCL standard titration solution consumed is definite, and pipette the lithium test solution according to the volume calculated, adopt the quality of the sodium that Flame Atomic Absorption Spectrometry Determination 100mg lithium is corresponding.

The assay method of the sodium content in the embodiment of the present invention comprises:

(1) prepare the lithium test solution

Get the smart lithium sample of 0.6g～1.4g, by the oxide layer on the pure water rinsing surface of flowing, put into rapidly the beaker of containing 100ml water, cover the table ware, treat the smart lithium sample dissolve complete in beaker, cooling after, obtain the lithium test solution;

(2) titration is processed, and calculates the volume of the lithium test solution that should pipette while needing the 100mg lithium

From the lithium test solution that pipettes 1.00ml beaker to conical flask, in conical flask, add 20ml water, 2 phenolphthalein ethanolic solutions that concentration is 10g/L, it by concentration, is the HCL standard titration solution titration of 0.100mol/L, to the solution in conical flask is red, disappear, the volume of the HCL standard titration solution consumed according to titration should pipette the volume of lithium test solution when calculating and needing the 100mg lithium;

(3) measure the sodium content in the lithium test solution pipetted

By the volume calculated, from beaker, measuring four parts of lithium test solutions in four volumetric flasks, the concentration that adds respectively 0ml, 1.0ml, 2.0ml, 3.0ml in four volumetric flasks is the sodium standard solution of 0.001mg/ml, be diluted with water to scale, shake up, with the sodium content in four volumetric flasks of Flame Atomic Absorption Spectrometry Determination, calculate the quality of the sodium that in the lithium sample, the 100mg lithium is corresponding.

As can be seen from the above technical solutions, the embodiment of the present invention has the following advantages:

The assay method of sodium content in embodiments of the present invention, by the water-soluble lithium test solution of making of smart lithium sample, adopt the HCL standard titration solution to carry out the titration processing to the lithium test solution pipetted, according to the volumescope of the HCL standard titration solution consumed, calculate while needing the 100mg lithium volume that should pipette the lithium test solution, and pipette the lithium test solution according to volume, and adopt the sodium content in Flame Atomic Absorption Spectrometry Determination lithium test solution, can effectively reduce the use of equipment, easy and simple to handle, reduce costs.

The accompanying drawing explanation

Fig. 1 is a schematic diagram of the assay method of a kind of sodium content in the embodiment of the present invention.

Embodiment

The embodiment of the present invention provides a kind of assay method of sodium content, adopts the sodium content in titrimetry and Flame Atomic Absorption Spectrometry Determination essence lithium, can effectively reduce the use of equipment, reduce costs, and easy and simple to handle.

Refer to Fig. 1, the embodiment for the assay method of a sodium content in the embodiment of the present invention comprises:

101, prepare the lithium test solution;

Get the smart lithium sample of 0.6g～1.4g, by the oxide layer on the pure water rinsing surface of flowing, put into rapidly the beaker of containing 100ml water, cover the table ware, treat the smart lithium sample dissolve complete in beaker, cooling after, obtain the lithium test solution.

102, titration is processed, and calculates the volume of the lithium test solution that should pipette while needing the 100mg lithium;

From the lithium test solution that pipettes 1.00ml beaker to conical flask, in conical flask, add 20ml water, 2 phenolphthalein ethanolic solutions that concentration is 10g/L, it by concentration, is the HCL standard titration solution titration of 0.100mol/L, to the solution in conical flask is red, disappear, the volume of the HCL standard titration solution consumed according to titration should pipette the volume of lithium test solution when calculating and needing the 100mg lithium;

In embodiments of the present invention, calculating the computing formula that should pipette the volume of lithium test solution while needing the 100mg lithium is:

$V=\frac{100\×1.00}{6.941\×C\left(\mathrm{HCL}\right)\×V\left(\mathrm{HCL}\right)}$

Wherein, V should pipette the volume of lithium test solution, units/ml while needing 100mg;

100 are the lithium amount that contains in the lithium test solution that should pipette, the mg of unit;

1.00 the volume of the lithium test solution pipetted during for titration, units/ml;

6.941 be the relative molecular mass of lithium;

C (HCL) is the concentration of HCI standard titration solution, the mg/ml of unit;

V (HCL) is the volume of the HCI standard titration solution of titration consumption, units/ml.

It should be noted that, in embodiments of the present invention, that to need the 100mg lithium be the volume that example is determined the lithium test solution need pipetted, in actual applications, can be also the volume of the standard lithium test solution that need to pipette by needing 50mg, 80mg lithium, therefore, when measuring sodium content, do not do restriction herein about the concrete quality of lithium.

103, measure the sodium content in the lithium test solution pipetted;

By the volume calculated, from beaker, measuring four parts of lithium test solutions in four volumetric flasks, the concentration that adds respectively 0ml, 1.0ml, 2.0ml, 3.0ml in four volumetric flasks is the sodium standard solution of 0.001mg/ml, be diluted with water to scale, shake up, with the sodium content in four volumetric flasks of Flame Atomic Absorption Spectrometry Determination, calculate the quality of the sodium that in the lithium sample, the 100mg lithium is corresponding.

Principle according to flame atomic absorption spectrometry, the absorbance A of sodium solution is directly proportional to the solubility C of sodium in solution, A=KC, wherein K is constant, in embodiments of the present invention, utilize HCL standard titration solution titration LiOH solution, the volume of the lithium test solution that should pipette while needing the 100mg lithium according to the volume of the HCL standard solution consumed is definite, and pipette the lithium test solution of four parts of these volumes, by standard addition method, by the concentration incremental order of the sodium standard solution added, measure the absorbance of four parts of solution on Atomic Absorption Spectrometer, namely at Atomic Absorption Spectrometer wavelength 670.8nm place, measure sodium content, according to absorbance, determine the quality of the sodium that the 100mg lithium is corresponding.

In embodiments of the present invention, by smart lithium sample is made to the lithium test solution, and adopt titrimetry to determine the volume of the lithium sample that should pipette while needing the 100mg lithium, according to this volume, pipette the lithium test solution, and adopt the Flame Atomic Absorption Spectrometry Determination sodium content, and can effectively avoid using the equipment such as glove box, balance argon bottle, only need to use several conventional chemical reagent and glassware, simple to operate, and the less investment of equipment and fund.

Above assay method to a kind of sodium content provided by the present invention is described in detail, for one of ordinary skill in the art, thought according to the embodiment of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims (2)

1. the assay method of a sodium content, is characterized in that, comprising:

(1) prepare the lithium test solution

Get the smart lithium sample of 0.6g～1.4g, by the oxide layer on the pure water rinsing surface of flowing, put into rapidly the beaker of containing 100ml water, cover the table ware, treat the smart lithium sample dissolve complete in beaker, cooling after, obtain the lithium test solution;

(2) titration is processed, and calculates the volume of the lithium test solution that should pipette while needing the 100mg lithium

From the lithium test solution that pipettes 1.00ml beaker to conical flask, in conical flask, add 20ml water, 2 phenolphthalein ethanolic solutions that concentration is 10g/L, it by concentration, is the HCL standard titration solution titration of 0.100mol/L, to the solution in conical flask is red, disappear, the volume of the HCL standard titration solution consumed according to titration should pipette the volume of lithium test solution when calculating and needing the 100mg lithium;

(3) measure the sodium content in the lithium test solution pipetted

By the volume calculated, from beaker, measuring four parts of lithium test solutions in four volumetric flasks, the concentration that adds respectively 0ml, 1.0ml, 2.0ml, 3.0ml in four volumetric flasks is the sodium standard solution of 0.001mg/ml, be diluted with water to scale, shake up, with the sodium content in four volumetric flasks of Flame Atomic Absorption Spectrometry Determination, calculate the quality of the sodium that in the lithium sample, the 100mg lithium is corresponding.

2. according to the method for claim 1, it is characterized in that, the volume of described HCL standard titration solution according to titration consumption calculates the computing formula that should pipette the volume of lithium test solution while needing the 100mg lithium and is:

$V=\frac{100\×1.00}{6.941\×C\left(\mathrm{HCL}\right)\×V\left(\mathrm{HCL}\right)}$

Wherein, V should pipette the volume of lithium test solution, units/ml while needing 100mg;

100 are the lithium amount that contains in the lithium test solution that should pipette, the mg of unit;

1.00 the volume of the lithium test solution pipetted during for titration, units/ml;

6.941 be the relative molecular mass of lithium;

C (HCL) is the concentration of HCI standard titration solution, the mg/ml of unit;

V (HCL) is the volume of the HCI standard titration solution of titration consumption, units/ml.

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