煤灰中的微量磷,一般采用灵敏度较高的钼兰比色法测定,在硅存在下,国家标准推荐以氢氟酸—高氯酸驱硅后完成测定;例行分析则以盐酸—高氯酸发烟浸提磷并使硅脱水,这样测得的结果,由于磷浸提不完全而系统偏低,而硅却使结果偏高。在适量硅存在下,由于两者的相互补偿而结果接近真实。然而高于50%以上的硅时,测定便 Phosphorus in coal ash is usually measured by Molano colorimetry with high sensitivity. In the presence of silicon, the national standard recommends the hydrofluoric acid-perchloric acid to be used to complete the determination of silicon. After routine analysis, hydrochloric acid-high Phosphorus chlorate leaches phosphorus and dehydrates silicon. The result of this measurement is that the system is low due to incomplete phosphorus leaching and the result is high with silicon. In the presence of a suitable amount of silicon, the result is close to true due to the mutual compensation between the two. However, when it is above 50% silicon, it is measured