In this study,zirconia containing refractory samples were decomposed by dilute nitric acid.The chloride ion content in the leaching solution was determined by thiocyanate spectrophotometry.The influences of the leachi...In this study,zirconia containing refractory samples were decomposed by dilute nitric acid.The chloride ion content in the leaching solution was determined by thiocyanate spectrophotometry.The influences of the leaching method of the sample pretreatment and the coloration condition of the solution to be tested on the test results were studied.The precision test was carried out and the results were compared with those determined by ion chromatography.The results showed that the zirconia containing refractories were boiled with dilute nitric acid to obtain the test solution.The influence of zirconium hydrolysis on determination was removed by centrifugation.The chlorine contents in zirconia containing refractories determined by spectrophotometry have low relative standard deviation(RSD),showing slight testing difference with those determined by ion chromatograghy.展开更多
The high chrome refractories were crushed,ground into powder and sampled.A mixture solution of sodium carbonate and sodium hydroxide was used to extract the powder samples.The extracted solution from the samples was m...The high chrome refractories were crushed,ground into powder and sampled.A mixture solution of sodium carbonate and sodium hydroxide was used to extract the powder samples.The extracted solution from the samples was mixed and reacted with diphenylcarbazide to form colored substance.The hexavalent chromium content in the samples was determined by spectrophotometry.The effects of the extracting conditions,the color reagent reaction conditions,the sample mass,the working curve and the trivalent chromium coexistence on the results were studied.The experiments about determination,recovery and precision were carried out.The relative standard deviation was less than 5%and the recovery rate was 98%-104%.展开更多
文摘In this study,zirconia containing refractory samples were decomposed by dilute nitric acid.The chloride ion content in the leaching solution was determined by thiocyanate spectrophotometry.The influences of the leaching method of the sample pretreatment and the coloration condition of the solution to be tested on the test results were studied.The precision test was carried out and the results were compared with those determined by ion chromatography.The results showed that the zirconia containing refractories were boiled with dilute nitric acid to obtain the test solution.The influence of zirconium hydrolysis on determination was removed by centrifugation.The chlorine contents in zirconia containing refractories determined by spectrophotometry have low relative standard deviation(RSD),showing slight testing difference with those determined by ion chromatograghy.
文摘The high chrome refractories were crushed,ground into powder and sampled.A mixture solution of sodium carbonate and sodium hydroxide was used to extract the powder samples.The extracted solution from the samples was mixed and reacted with diphenylcarbazide to form colored substance.The hexavalent chromium content in the samples was determined by spectrophotometry.The effects of the extracting conditions,the color reagent reaction conditions,the sample mass,the working curve and the trivalent chromium coexistence on the results were studied.The experiments about determination,recovery and precision were carried out.The relative standard deviation was less than 5%and the recovery rate was 98%-104%.
