The removal of heavy metal from sludge before disposal or application to farmland is a necessary step to achieve a more safe sludge usage or disposal. Chemical extraction using inorganic acids (nitric, hydrochloric) and organic acids (citric, oxalic) were tested for extraction of chromium, copper, nickel, lead and zinc from contaminated sewage sludge at different pH and reaction time. Results r...

The removal of heavy metals (Cr, Cu, Zn, Ni and Pb) from anaerobically digested sludge from the Yuen Long wastewater treatment plant, Hong Kong, has been studied in a batch system using isolated indigenous iron-oxidizing bacteria. The inoculation of indigenous iron-oxidizing bacteria and the addition of FeSO4 accelerated the solubilization of Cr, Cu, Zn, Ni and Pb from the sludge. pH of the slu...

This investigation was undertaken to study Pb uptake by small free floating aquatic plant Lemna minor from wastewater polluted by contaminated with heavy metals. Metal accumulation process was affected by various parameters such as different pH, temperature and concentration of Pb solution. Total chlorophyll contents in Lemna minor was adversely affected from increased with increasing Pb concen...

Waste materials with no further treatment such as orange barks from commercial oranges may act as adsorbent for the removal of Pb. Batch kinetic and equilibrium experiments were conducted to study the effects of contact time, initial pH, adsorbent dose and initial concentration of lead. The results show that the equilibrium was achieved less than 30 min of contact time. Three adsorption isother...

Discharge of untreated industrial wastewater containing heavy metals such as Pb2+ is hazardous to the environment due to their high toxicity. This study reports on the adsorption, desorption, and kinetic study on Pb2+ removal from aqueous solutions using wood/Nano-manganese oxide composite (WB-NMO). The optimum pH, contact time and temperature for adsorption were found...

Constructed wetland (CW) with monoculture of Arundo donax L. was investigated for the posttreatment of anaerobic bioreactor (ABR) treating combined industrial wastewater. Different dilutions of combined industrial wastewater (20, 40, 60, and 80) and original wastewater were fed into the ABR and then posttreated by the laboratory scale CW. The respective removal efficiencies of COD, BOD, TSS, ni...

background: in recent years, various toxic chemicals/compounds have been widely detected at dangerous levels in drinking water in many parts of the world posing a variety of serious health risks to human beings. one of these toxic chemicals is lead, so this paper aimed to evaluate of efficiency coconut husk as cheap adsorbent for removal lead under different conditions. methods: in the spring o...

A laboratory investigation provided preliminary comparison of trace element contaminant water treatment capabilities for four iron-based filter materials. The iron-based filter materials tested were zero-valent iron (ZVI), porous iron composite (PIC), sulfur modified iron (SMI), and iron oxide/hydroxide (IOH). Two types of trace element contaminant solutions were tested, one combined As, Cr, an...

Cucumissativus peel (CSP), was investigated as a new adsorbent for Pb(II) removal from aqueous solution under several varying conditions such as pH, adsorbent dosage, and contact time. Maximum metal sorption was found to occur at initial pH 5.0. The adsorption capacity of CSP was found to be 28.25mg/g for initial Pb(II) concentration of 25 mg/l at 25°C. The equilibrium data best fitted to the L...

background: the presence of lead in natural waters has become an important issue around the world. lead has been identified as a highly toxic metal that can cause severe environmental and public health problems and its decontamination is of utmost importance. the aim of this work was to evaluate the adsorption of lead (pb(ii)) on waste tea leaves as a cheap purification method. methods: in this...