GB/T 23513.5-2009Chemical analysis methods for germanium concentrate - Part 5: Determination of silica content - Gravimetry (English PDF)

Foreword

GB/T 23513 Chemical analysis methods for germanium concentrate is consisted of five parts as follows.

- Part 1. Determination of germanium content - Potassium iodate titration;

- Part 2. Determination of arsenic content - Ferrous ammonium sulfate titration;

- Part 3. Determination of sulfur content - Barium sulfate gravimetry;

- Part 4. Determination of fluoride content - ISE;

- Part 5. Determination of silica content - Gravimetry. This part is part 1.

1 Scope

This part of GB/T 23513 specifies the determination method of silica content in germanium concentrate.

This part applies to the determination of silica content in germanium concentrate. Determination range. 0.5%-60%.

2 Methods and principles

Melt the sample with sodium hydroxide and sodium peroxide. Use water to leach. Add hydrochloric acid to dehydrate, so as silicate is precipitated. Evaporate to remove the germanium. Add gelatin to condense, filter and separate the silicate. Weigh the mass after ashing and burning.

3 Reagents

Unless otherwise stated, only analytical reagents AND distilled water or water with equivalent purity can be used in the analysis.

3.1 Sodium hydroxide (NaOH).

3.2 Sodium peroxide (Na2O2).

3.3 Hydrochloric acid (rho 1.19 g·mL-1).

3.4 Hydrochloric acid (1 + 3).

3.5 Hydrochloric acid (5 + 95).

3.6 Gelatin solution (1%). Prepare when using.

4 Analysis steps

7 Quality assurance and control

It shall use the national standard materials or industry-level standard materials (if there is no such sample, it may use control sample to substitute). Verify the validity of this analytical method standard once a week or every 2 weeks. When the process is out of control, the root cause reason shall be found out; and re-verify it after correcting the error. >8.00-10.00 0.40 >10.00-50 0.50 […]