GB 32449-2015Feed additive - Magnesium sulphate (English PDF)

1.0 Clarity test Clarification Fineness (400µm test sieve) /% >=95 - Test Method

4 Warning. some of the procedures specified test methods can lead to dangerous situations, the operator should take appropriate safety and health practices. The standard test methods the reagents and water, in the absence of other requirements specified, are by analytical reagent 6682 and GB/T in Three water.

4.1 sensory testing The appropriate amount of sample is placed in a clean white paper, color and observed under natural light state.

1.5 Sulfate Chemical synthesis. <=

0.1 Salt Lake Bittern method. <=

4.2.1 Reagents and materials

4.2.1.1 solution of ammonium chloride. 50g/L.

4.2.1.2 ammonia solution. aqueous ammonia = 23.

4.2.1.3 ammonium carbonate solution (200g/L). Weigh 20g of ammonium carbonate, aqueous ammonia 20mL was added, water was added to 100mL.

4.2.1.4 sodium dihydrogen phosphate solution (50g/L). Weigh 5g of sodium dihydrogen phosphate, add appropriate amount of water dissolved, add water to 100mL.

4.2.1.5 barium chloride solution (50g/L). Weigh 5g barium chloride, add appropriate amount of water dissolved, add water to 100mL.

4.2.2 Analysis of step Identification of magnesium ions

4.2.2.1 The sample was dissolved in water, was added aqueous ammonia solution (4.2.1.2), i.e., a white precipitate of ammonium chloride was added dropwise a solution of (4.2.1.1), the precipitate was dissolved again Was added a solution of sodium dihydrogen phosphate (4.2.1.4) to form a white precipitate, this precipitate was not dissolved in the ammonia. Identification of sulfate ion

4.2.2.2 The sample was dissolved in water, a solution of barium chloride (4.2.1.5), a white precipitate formed.

4.3 Determination of magnesium sulfate and magnesium content

4.3.1 Principle Masking with a small amount of triethanolamine of trivalent iron and aluminum ions added pH~10 ammonia - ammonium chloride buffer solution, chrome black T as indicator. The total amount of disodium ethylenediaminetetraacetate (EDTA) titration standard titration solution calcium and magnesium. Under the conditions of the test solution pH~

12.5 to the Cal as indicator, with disodium ethylenediaminetetraacetic acid (EDTA) Standard Titration titration of calcium. Subtracting from the total amount of calcium and magnesium in the calcium content, to calculate the magnesium content.

4.3.2 Reagents

4.3.2.1 ammonia solution. aqueous ammonia = 12.

4.3.2.2 triethanolamine. Triethanolamine water = 13.

4.3.2.3 ammonia - ammonium chloride buffer solution (pH~10). Weigh 27g of ammonium chloride, dissolved in appropriate amount of water, add 197 mL of aqueous ammonia, diluted with water to 500mL.

4.3.2.4 sodium hydroxide solution. 50g/L.

4.3.2.5 disodium edetate (EDTA) standard titration solution [c (EDTA) = 0.05mol/L]. prepared according to GB/T 601 requirements.

4.3.2.6 disodium edetate (EDTA) standard titration solution [c (EDTA) = 0.02mol/L]. prepared according to GB/T 601 requirements.

4.3.2.7 chrome black T indicator. 5g/L.

4.3.2.8 indicator in the Cal. Cal - 0.1g taken and dried for 2h at 105 °C NaCl10g, milled Mix well.

4.3.3 Analysis of step

4.3.3.1 Preparation of test solution Weigh about 10g of magnesium sulfate heptahydrate or a 5g sample over anhydrous magnesium sulfate, accurate to 0.0001g, was placed in a 250mL beaker was added 100mL Dissolved in water. All transferred to 250mL volumetric flask, diluted with water to the mark. If necessary dry filtration, the solution was a solution A, for Determination of calcium and magnesium content, calcium content, the chloride content.

4.3.3.2 Determination Determination of calcium and magnesium content 4.3.3.2.1 Pipette with a pipette 10mL solution A, placed in 250mL Erlenmeyer flask, was added 40mL of water, 5 mL triethanolamine (4.3.2.2), with Aqueous ammonia solution (4.3.2.1) adjusted to pH 7-8, was added 10mL of ammonia - ammonium chloride buffer solution (4.3.2.3) and a small amount of Eriochrome Black T (4.3.2.7), With disodium edetate Standard Solution (4.3.2.5) to the solution titrated from purple to pure blue as the end point. At the same time a blank test. Pipette with a pipette 10mL of water, placed in 250mL Erlenmeyer flask, and the kind of operation and other reagents were added Are the same number of assays. 4.3.3.2.2 Determination of calcium content Pipette with a pipette 10mL solution A, placed in 250mL Erlenmeyer flask, was added 25mL of water, 5 mL of triethanolamine solution (4.3.2.2). 5mL sodium hydroxide solution was added with shaking (4.3.2.4), plus a small amount in the Cal indicator (4.3.2.8), labeled with disodium edetate Quasi titration solution (4.3.2.6) to the solution titrated from purple to pure blue as the end point. At the same time a blank test. Pipette with a pipette 10mL of water, placed in 250mL Erlenmeyer flask, other types of operations and the addition of reagents And number are the same assay.

4.3.4 Calculation of results showing X1 to a magnesium content of over anhydrous magnesium sulfate (MgSO4 · H2O) [or magnesium sulfate heptahydrate (MgSO4 · 7H2O), or magnesium (of Mg)] The mass fraction, expressed in% value, calculated according to formula (1). X1 = 25 × (V1-V1,0) c1M1 × 10-3 m × 100-lambdaX2 = 2.5 × (V1-V1,0) c1M1 m -lambdaX2 (1) X2 calcium content of calcium (Ca) mass fraction, expressed in%, calculated according to formula (2). X2 = 25 × (V2-V2,0) c2M2 × 10-3 m × 100 = 2.5 × (V2-V2,0) c2M2 (2) Where. C1

--- disodium ethylenediaminetetraacetate (EDTA) accurate value of the concentration of the standard titration solution (4.3.2.5) in units of moles per liter (Mol/L); Volume (EDTA) Standard Solution (4.3.2.5) the titration of the sample Vl

--- calcium and magnesium total number of consumed Disodium ethylenediaminetetraacetate Value in milliliters (mL); Blank Test Titration of Calcium and Magnesium in the total amount of consumed V1,0

--- disodium edetate (EDTA) Standard Solution (4.3.2.5) of the body Product of value, in milliliters (mL); C2

--- disodium ethylenediaminetetraacetate (EDTA) accurate value of the concentration of the standard titration solution (4.3.2.6) in units of moles per liter (Mol/L); V2

--- titration sample content of calcium disodium edetate consumption (EDTA) standard titration solution volume value (4.3.2.6), and Milliliters (mL); V2,0

--- blank titration calcium content consumed disodium edetate (EDTA) titration volume of standard solution (4.3.2.6) of Value in milliliters (mL);

--- m sample mass value in grams (G);

--- magnesium sulfate with a Ml product over anhydrous magnesium sulfate (MgSO4 · H2O) timing, the value of its molar mass M (MgSO4 · H2O) = 138.4 [or magnesium sulfate heptahydrate (MgSO4 · 7H2O) timing, the value of its molar mass M (MgSO4 · 7H2O) = 246.5; or magnesium (Mg) timing, the value of its molar mass M (Mg) = 24.31], in units of grams per mole (g/mol);

--- M2 numerical molar mass of calcium (Ca), in units of grams per mole (g/mol) (M2 = 40.08); [lambda]

--- magnesium sulfate to a product over anhydrous magnesium sulfate (MgSO4 · H2O) timing, scaling factor [lambda] Calcium (MgSO4 · H2O) = 3.453 [Or magnesium sulfate heptahydrate (MgSO4 · 7H2O) timing, lambda (MgSO4 · 7H2O) = 6.150; or magnesium (Mg) timing, lambda (Mg) = 0.6065]. In the arithmetic mean of the two determination results parallel the measurement results, the result to one decimal place reserved. The absolute difference determination results MgSO4 · 7H2O parallel to no more than 0.5%, to no more than MgSO4 · H2O 0.3%, to no more than 0.05% Mg.

4.4 Determination of Arsenic According to

GB/T 13079-2006 measurement Chapter 5, wherein the sample processing carried out in 5.4.1.2.1.

4.5 Determination of lead content According to

GB/T 13080-2004 assay in which the sample is dissolved in

GB/T 13080-2004 performed in 7.1.2.1. Measurement sample required buckle In addition to background.

4.6 Determination of mercury content Measured by GB/T 13081.

4.7.1 Principle With

GB/T 3051-2000 Chapter 3.

4.7.2 Reagents

4.7.2.1 mercuric nitrate standard titration solution. c [1/2Hg (NO3) 2] = 0.05mol/L, according to

GB/T 3051-2000 with a predetermined

4.6 And system calibration.

4.7.2.2 The remaining 3051-2000 Chapter 4 with GB/T .

4.7.3 Instruments and equipment With

GB/T 3051-2000 Chapter 5.

4.7.4 Analysis of step Pipette with a pipette 50mL solution A (4.3.3.1), placed in 250mL Erlenmeyer flask, add 3 drops of bromophenol blue indicator solution was added dropwise nitric acid Solution just turns from blue to yellow, and then an excess of 5 drops. Add 1mL diphenylcarbazone hydrazide indicator solution, using microburette, with nitric acid Mercury standard solution was titrated to titrate the solution from yellow to purple, is the end. At the same time a blank test. Pipette with a pipette 50mL of water, placed in 250mL Erlenmeyer flask, other types of operations and the addition of reagents And number are the same assay. The waste liquid after titration saved, processing predetermined

GB/T 3051-2000 of Appendix D.

4.7.5 Calculation of results showing X3 chloride content of chlorine (Cl) mass fraction, expressed in%, calculated according to formula (3). X3 = 5 × (V3-V3,0) c3M3 × 10-3 m × 100 = 0.5 × (V3-V3,0) c3M3 (3) Where. Numerical volume V3

--- mercury nitrate titration standard solution (4.7.2.1) titration test solution consumed, in milliliters (mL); Values V3,0

--- volume of mercury nitrate titration standard solution (4.7.2.1) titration of the blank test solution consumed, in units of ml (ML); C3

--- accurate value of the concentration of mercury nitrate Standard Solution (4.7.2.1), in units of moles per liter (mol/L);

--- M3 molar mass of chlorine (Cl) values, in units of grams per mole (g/mol) (M = 35.45);

--- m sample mass values, in units of grams (g). In the arithmetic mean of the two determination results parallel the measurement results, the result to one decimal place reserved. The absolute difference between the two measurement results in terms of magnesium sulfate heptahydrate not more than 0.01% to not greater than a water 0.1% magnesium.

4.8 Clarity test Weigh 5.0g ± 0.1g sample was dissolved was added 20mL of water, the solution should be clear and transparent without white turbidity.

4.9 Determination of fineness

4.9.1 Principle The test sample is sieved, particle size is determined by the mass of products in accordance with the sample test sieve.

4.9.2 instruments and equipment Test sieve. phi200 × 50-0.4/

0.25 GB/T 6003.1-2012.

4.9.3 Analysis of step Weigh 10g sample accurately to 0.1g, placed in a test sieve, and the sieve cover fitted sieved undersize. In the horizontal direction two times/s. Shaking speed, until no test sieve until the sample by collecting the undersize falls under the sieve, sieve mass was weighed to the nearest 0.1g.

4.9.4 Calculation of results showing X4 fineness mass fraction, expressed in%, calculated according to formula (4). X4 = m1 m2 × 100 (4) Where.

--- the mass M1 test sieve material in grams (G);

--- M2 sample mass, in grams (g). The arithmetic average of the measurement results of two parallel measurement results, the results of a number of reservations to. The absolute difference determination results parallel to less than 1%.