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Determination of Hexavalent Chromium in Refractories by Diphenylcarbazide Spectrophotometry

作者:FU Yuanyuan1,HAN Junhua2,CAO Haijie2,LEI Xiaoyu2,HAN Dan2,XU Xiaoying2

作者單位:1. CISDI Engineering Co., Ltd.2. Sinosteel Luoyang Institute of Refractories Research Co., Ltd.

刊名:China’s Refractories

ISSN:1004-4493

出版年:2021-09-15

卷:30

期:3

起頁:28-32

止頁:

分類號:O657.3;TQ175.1

語種:英文

關(guān)鍵詞:

內(nèi)容簡介

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%.

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