GB/T 3653.3-2023Ferroboron—Determination of silicon content—Perchloric acid dehydration-gravimetric method (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document is Part 3 of GB/T 3653. GB/T 3653 has published the following parts.

---Chemical analysis method of ferroboron Determination of boron content by alkali titration method;

---Chemical analysis method of ferroboron Determination of carbon content by gas volumetric method;

---Determination of ferrosilicon content by perchloric acid dehydration gravimetric method;

---Determination of boron, iron and aluminum content by EDTA titration method;

---Chemical analysis method of ferroboron, chromatographic separation, barium sulfate gravimetric method, determination of sulfur content;

---Chemical analysis method of ferroboron Antimony phosphorus molybdenum blue photometry method to determine phosphorus content;

---Determination of boron, iron, and sulfur content by infrared absorption method.

This document replaces GB/T 3653.3-1988 "Methods for chemical analysis of ferric boron - Determination of silicon content by perchloric acid dehydration gravimetric method". and Compared with GB/T 3653.3-1988, in addition to structural adjustments and editorial changes, the main technical changes are as follows:

a) Changed the content of the principle (see Chapter 4, Chapter 2 of the 1988 edition);

b) Changed "Reagents and Materials" (see Chapter 5, Chapter 3 of the 1988 edition);

c) Added "instruments and equipment" (see Chapter 6);

d) Added "number of measurements" (see 8.1);

e) The sample fusion method was changed from "acid fusion first and then alkali fusion" to "direct alkali fusion" (see 8.4.1, 5.3.1 of the 1988 edition);

f) Changed the amount of perchloric acid added, changing "add 30mL perchloric acid" to "add 40mL perchloric acid" (see 8.4.2, 1988 version 5.3.2);

g) Changed the precipitation ignition temperature, changing "1000°C" to "1050°C" (see 8.4.6, 5.3.6 of the 1988 edition);

h) Changed "Calculation and Expression of Analysis Results" (see Chapter 9, Chapter 6 of the 1988 edition);

i) Changed "permissible difference" to "precision" (see Chapter 10, Chapter 7 of the 1988 edition);

j) Added test report (see Chapter 11);

k) Added "Flowchart of Sample Analysis Results Acceptance Procedure" (see Appendix A).

Introduction

Since there are many detection elements involved in the ferroboron detection process, the applicable scope and applicable methods of the elements are different. To ensure boron The iron detection standards are convenient and accurate, and a national standard system has been established to support the detection of ferroboron based on the analysis methods of different elements of ferroboron.

The GB/T 3653 ferroboron series analysis method is the basic standard for ferroboron detection in my country and consists of the following seven parts.

---Chemical analysis method of ferroboron Determination of boron content by alkali titration method. The purpose is to measure the boron content in ferroboron, using alkali titration.

---Chemical analysis method of ferroboron. Determination of carbon content by gas volumetric method. The purpose is to measure the carbon content in ferroboron, using the gas volumetric method.

---Determination of ferrosilicon content by perchloric acid dehydration gravimetric method. The purpose is to measure the silicon content in ferroboron and use perchloric acid to dehydrate it. gravimetric method.

---Determination of boron, iron and aluminum content by EDTA titration. The purpose is to measure the aluminum content in ferroboron, using the EDTA titration method.

---Chemical analysis method of ferroboron Chromatographic separation Barium sulfate gravimetric method Determination of sulfur content. The purpose is to measure the sulfur content in ferroboron, using Chromatographic separation with barium sulfate gravimetric method.

---Chemical analysis method of ferroboron. Determination of phosphorus content by antimony phosphorus molybdenum blue photometry. The purpose is to measure the phosphorus content in ferroboron, using antimony phosphorus molybdenum Blue photometry.

---Determination of boron, iron, and sulfur content by infrared absorption method. The purpose is to measure the sulfur content in ferroboron, using infrared absorption method.

Warning---Personnel using this document should have regular laboratory work experience. This document does not address all possible security issues question. Users are responsible for taking appropriate safety and health measures and ensuring compliance with the conditions stipulated in relevant national regulations.

1 Scope

This document describes a method for the determination of the silicon content in ferroborates using the perchloric acid dehydration gravimetric method.

This document is applicable to the determination of silicon content in ferroboron. The determination range (mass fraction) is: 0.50%~16.00%.

2 Normative reference documents

The contents of the following documents constitute essential provisions of this document through normative references in the text. Dated citations files, only the version corresponding to that date applies to this document. For undated referenced documents, the latest version (including all amendments) applies to this document.

GB/T 4010 Collection and preparation of samples for chemical analysis of iron alloys

GB/T 6379.1 Accuracy of measurement methods and results (correctness and precision) Part 1: General principles and definitions

GB/T 6379.2 Accuracy of measurement methods and results (correctness and precision) Part 2: Determination of repeatability of standard measurement methods Basic methods of sex and reproducibility

GB/T 6682 Specifications and test methods for water used in analytical laboratories

GB/T 8170 Numerical rounding rules and expression and determination of limit values

3 Terms and definitions

There are no terms or definitions to be defined in this document.

4 Principles

The sample is melted with sodium carbonate and sodium peroxide to convert the silicon into silicate, acidified with hydrochloric acid, and dehydrated with perchloric acid for secondary smoking.

Filter and wash, burn the precipitate at 1050°C and then cool it. Use methanol to volatilize the boron at low temperature, burn to a constant amount, and use hydrofluoric acid to tetrafluoride the silicon.

The silicon is volatilized and removed, and then burned to a constant amount. The silicon content is calculated based on the mass difference before and after hydrofluoric acid treatment.

5 Reagents and materials

Unless otherwise stated, only approved analytical grade reagents and grade three or above evaporators that comply with GB/T 6682 are used in the analysis. Distilled or deionized water or water of equivalent purity.

5.1 Anhydrous sodium carbonate, solid.

5.2 Sodium peroxide, solid.

5.3 Mix flux, 2 parts sodium peroxide and 1 part anhydrous sodium carbonate, mix well.