Open AccessDifferentiation of digestion method for heavy metals in river sediments based on organic matter gradients
Author(s) -
Jinbao Liu,
Qiu Hua Shen,
Wei Fang,
Zhenni Guo,
Ying-jie Tian
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/467/1/012128
Subject(s) - organic matter , sediment , environmental chemistry , digestion (alchemy) , heavy metals , environmental science , nitric acid , pollution , chemistry , hydrochloric acid , mercury (programming language) , metal , geology , chromatography , ecology , inorganic chemistry , biology , paleontology , organic chemistry , computer science , programming language
Heavy metal detection in river sediments is critical in evaluating heavy metal pollution levels, risk and control in these matrices. Most of existing detection methods have the disadvantage of low recovery rate and high total acid consumption. Due to continuous accumulation of metal and relative high content of organics in river sediments, this paper focused on studying differentiated digestion method of heavy metals based on organics gradient grading. Surface river sediment samples were collected from 26 different rivers and lakes within the Qiantang River basin (e.g. Hangzhou and Jiaxing). Organic matter content in these samples were tested and these samples were divided into 8 groups according to content of organic matter. This was followed by testing the effects of hydrochloric acid, nitric acid and hydrofluoric acid on the digestion of heavy metals (Cu, Zn and Ni). The optimum digestion system of heavy metals in river sediments based on organic matter gradients was established. Results demonstrated that digestion system can achieve high recovery rate (90%∼110%) and an average dectection accuracy, while total acid consumption is about 10.54 mL, which is less than that of the Chinese standard digestion method (19mL). This means that the digestion system proposed in this paper is environmentally friendly.