Release behavior of chromium from tannery sludge

Removal of Chromium and Organic Pollutants from Industrial Chrome Tanning Effluents by Electrocoagulation

“…This observation is in line with other reports [22]. Organicbound chromium [33] probably lowers the efficiency of Cr(III) removal by hydroxide precipitation and the Cr(III) discharge limit could not be reached. COD and BOD 5 reductions were maximal around 50 % in the same pH range of 8-9.…”

Cr(III) accumulation and phytoavailability in alkaline soils contaminated by tannery sludge

“…Our results showed that 82% of Cr(III) in the sludge is in the F4 fraction. Here Cr(III) distribution in the sludge was similar to that reported by Chuan and Liu (1996), in which the Cr(III) fraction in the tannery sludge was analyzed by the procedure of Tessier et al (1979). It was concluded that 2 mol L -1 HCl extractable Cr(III) in the soils was mainly derived from the sludge.…”

Chemistry of Chromium in Soils with Emphasis on Tannery Waste Sites

“…In another study Chuan and Liu (1995) using the Tessier et al (1979) scheme, sequentially extracted Cr from a pig tannery sludge and other tannery plants representative of Taiwan. Ninety-three percent of the 17,000 mg total Cr/kg soil was bound to the Fe-Mn oxides while the remainder was partitioned in the organic and residual fractions and Cr in the exchangeable fraction was negligible.…”