苛性碱、碳酸碱和全碱的同时流动注射分析

Simultaneous Determination of Caustic Soda, Sodium Carbonate and Total Soda in Sodium Aluminate Solutions by Flow Injection Titration

采用流动注射滴定技术实现了氧化铝生产过程中铝酸钠溶液中苛性碱、碳酸碱和全碱的同时自动分析。以磺基水杨酸为载流，它既为滴定剂又是铝的掩蔽剂；酚酞和甲基橙混合液为试剂流，它们是苛性碱、碳酸碱和全碱的指示剂。该法可测定6．2～30．9g/L的碳酸碱和3．1～15．5g/L的苛性碱（均以Na2O计），测定速率30个样/h，相对标准偏差优于0．5％（n＝11，Na2O＝21．94g/L）。

Simultaneous determination of caustic soda, carbonate,and total soda in sodium aluminate solutions is realized by flow injection titration with a mixture of methyl orange and phenolphthalein as the corresponding indicators for the determination of caustic soda, sodium carbonate and total soda. Sulfosalicylic acid, the carrier, is both the titrant and complexing agent for aluminum.The method can be used for the the analysis of the sample containing caustic soda, sodium carbonate and total soda in the range of 6. 2 ~ 30. 9 g/L and 3. 1 ~ 15- 5 g/L (expressed as Na2O) with a sampling freqUency of 30 Samples per hour. A relative standard deviation of 0. 5% is obtalned for 11determinations of a typical sample containing 21. 94 g/L of sodium oxide.