论文部分内容阅读
在用EDTA容量法测定黑钨精矿中的钙的操作中,为使CaC_2O_4沉淀完全,过滤前要求“静置2h”。这样,在用于配合选矿流程控制和产品配批时,即有分析结果不及时之弊。为此,笔者对原规程稍加改变,把陈化CaC_2O_4时间由2.5h缩短为0.5h。将试料熔块完全溶于饱和草酸铵溶液后,调节试液pH3～4,然后根据操作过程中试液体积的增加,以每增加10ml加草酸铵0.5g的比例,在不断搅拌下加入粉末状草酸铵(一般加入量为2g)。并剧烈搅拌30
In the determination of calcium in wolframite concentrate by EDTA volumetric method, it is required to “stand for 2h” before filtration in order to precipitate CaC_2O_4 completely. In this way, when used in conjunction with the dressing process control and product batch, that is, the analysis results are not timely. To this end, the author of the original rules a little change, the aging of CaC_2O_4 time from 2.5h to 0.5h. After the sample frit is completely dissolved in the saturated ammonium oxalate solution, the pH of the test solution is adjusted to 3 to 4, and then the volume of the test solution is increased according to the increase of the volume of the test solution during the operation. With the addition of 0.5 g of ammonium oxalate for every 10 ml, Ammonium oxalate (usually added in an amount of 2g). And stir vigorously 30