| 摘要 |
Nitrobenzene-sulphonic acid is prepared by gradual heating of a mixture of nitrobenzene with twice its volume of sulphuric acid of specific gravity 1.80. The mixture turns light red at 210 DEG C. and is then cautiously heated to 220 DEG C., at which temperature it is dark red and almost opaque. It is maintained at this temperature for ten minutes, then rapidly cooled and tested by dropping one minim into 50 c.c. of water. If oily drops form, the heating, cooling and testing are repeated until the formation of such drops ceases. The product so obtained is used as an electrolyte for effecting the recovery of sulphated lead acid accumulators. |
