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《常用电镀溶液的分析》一书中对氨三乙酸-氯化铵镀锌溶液硼酸的测定提供的方法是加柠檬酸钠-甘油混合液,用氢氧化钠直接滴定至酚酞变红色:或用EDTA掩蔽锌,先用氢氧化钠中和至甲基红变黄色,再加甘露醇后用氢氧化钠滴定至酚酞变红。但是这二个方法测定的结果都严重偏高。作者着重试验了镀液是大量氯化铵(270g l~(-1))对测定硼酸的干扰情况。采用加过量氢氧化钠,煮沸除去铵盐,再用盐酸中和过量的氢氧化钠,最后以甘油强化硼酸,用氢氧化钠滴定至酚酞变红色,得到满意的结果。
“Analysis of commonly used plating solution,” a book on the determination of boric acid nitrilotriacetic acid - ammonium chloride zinc plating solution is provided by adding sodium citrate - glycerol mixture, titration with sodium hydroxide to phenolphthalein red: or EDTA mask zinc, first with sodium hydroxide and methyl red yellow, plus mannitol with sodium hydroxide titration to phenolphthalein red. However, the results of these two methods are seriously high. The author focused on testing the bath is a lot of ammonium chloride (270g l ~ (-1)) on the determination of boric acid interference. Addition of excess sodium hydroxide, boil to remove the ammonium salt, hydrochloric acid and then excess sodium hydroxide, and finally to strengthen the boric acid with glycerol, titration with sodium hydroxide to phenolphthalein red, get satisfactory results.