Date pits waste as a solid phase extraction sorbent for the analysis of lead in wastewater and for use in manufacturing brick: An eco-friendly waste management approach

Abstract

Lead (Pb(II)), an extremely hazardous heavy metal that has been shown to have detrimental effects on both the environment and humans, mostly gets into the ecosystem through industrial activities. In this work, a new solid-phase extraction (SPE) based on treated date pits bio-sorbent and iCAP Q inductively-coupled plasma mass spectrometry (iCAP Q ICP/MS) method has been optimized for the trace determination of Pb(II) in various industrial wastewater effluents. A cost-effective biomass material was prepared from date pits (DP), and chemically modified with H2O2 and successively used as SPE bio-sorbent for Pb(II) extraction. Extracting solutions for instance H2SO4, HNO3 and HCl at various concentrations (1–5 mM) were optimized, and best extraction of Pb(II) was obtained by HCl (1 mM). The optimized SPE and iCAP Q ICP/MS method has offered excellent validation conditions in terms of coefficient of determination (CoD, R2 > 0.999), detection limit (DL, 0.011 µg/L), quantification limit (QL, 0.034 µg/L), and run-to-run and day-to-day precision (RSD < 6 %). The optimized procedure was practically applied in the determination of Pb(II) in industrial wastewater comprising iron and steel, textile, printing and battery industries. Among the analyzed samples, the battery industry produced higher amounts of Pb(II) (18.55 µg/L) followed by iron and steel (14.65 µg/L), petroleum (12.38 µg/L) printing (5.78 µg/L) and textile (3.76 µg/L) industries. The recovery values were achieved between 95 % and 99 %. The obtained results have established the appropriateness of the offered technique as a new useful method for the routine examination of Pb(II) in industrial wastes. In addition, the current method could be expansively used in the proficient removal and identification of other heavy metals contaminants from similar matrices. Further, the metal ions saturated bio-sorbents were used in the preparations of bricks and it was found to be a successful approach for heavy metals and agricultural waste management.