Premium
Efficiencies of Extractants Used in Analyses of Heavy Metals in Sludges
Author(s) -
Neuhauser E. F.,
Hartenstein R.
Publication year - 1980
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq1980.00472425000900010006x
Subject(s) - extraction (chemistry) , heavy metals , sewage sludge , soil water , chemistry , metal , acetic acid , environmental chemistry , sewage , yield (engineering) , environmental science , chromatography , environmental engineering , metallurgy , biochemistry , materials science , organic chemistry , soil science
A comparison of extractability was made for three solvents commonly used in estimating availability of heavy metals in soils to living plants. Small, intermediate, and large amounts of heavy metals were removed, respectively, from an anaerobic digest of a sewage sludge with 2.5% acetic acid, 0.1 N HCl, and 1.0 N HCl respectively. With 10, 20, 30, and 40 ml 1 N HCl per g sludge, approximately the same amount of each heavy metal was extracted during 1 hour of shaking, while for 0.1 N HCl and 2.5% acetic acid increasing amounts were extracted at 10, 20, and 30 ml/g, with somewhat higher or lower amounts being obtained at a ratio of 40 ml extractant per g sludge. With 0.1 N HCl, an extraction period of 0.5 hour appeared to be sub‐optimal, while periods longer than 1 hour did not yield significantly greater extractability except for Cd, extracted for 3 hours. Extraction of Ni for 5 hours and Pb for 5 or 7 hours resulted in significantly less metal than was obtained at 1 hour. Since it is highly likely that availability of heavy metals to plants will depend on numerous and unpredictable variables, it is proposed that until such factors are resolved, a standard extraction procedure be used by all workers on sludges and soils. This would provide a basis for comparisons of published data.