Determination of sulphide in effluent streams using a solid-phase lead(II) chromate reactor incorporated into a flow-injection system

The determination of sulphide in waste water (effluent) from a dairy farm, using a solid-phase reactor incorporated into a flow-injection system, was investigated. The reactor packing material consisted of PbCrO4 suspended on alumina, and the chromate ions were released into the carrier stream when PbS, which is less soluble than PbCrO4, was formed. The chromate ions were detected spectrophotometrically at 370 nm. The linear response range of the method was between 10 and 50 mg l(-1), with a detection limit of 3.7 mg l(-1). The relative standard deviation was <3% for n = 12 at 30 mg l(-1) S2-. (C) 1998 Elsevier Science B.V. All rights reserved.