Methods:After decompounded the sample by nitric acid, then to detect using both flame and graphite oven atomic absorption spectrophotometer.
方法：将样品经硝酸分解后，采用火焰原子吸收法和石墨炉原子吸收法分析测定。
2
The results showed that HF acid has remarkable deashing capacity for coal and graphite with high Si and low Ca content.
结果表明，HF酸对高硅低钙含量的煤和石墨有显著的脱灰效果；
3
The application of ferreous synthetic furnace, triad graphite synthetic furnace and diad graphite synthetic furnace in the production of high purity hydrochloric acid is compared.