Highpurityarsenic trioxid was obtained from the 2nd stage filtrate by reduction with SO2 flue gas, freeze crystallization, water dissolving, filtering and refining.
二段浸出后的滤液用二氧化硫烟道气还原，还原液经冷冻结晶、水溶、过滤、精制后可得纯度较高的精白砷。
2
A new method in which trace arsenic in high-purity germanium dioxide is determined using silver nitrate absorption photometry is described in this discussion.