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The utilization of waste resources to synthesize functional materials is crucial for achieving environmentally sustainable development. In this context, the current investigation aims to develop a new material using waste chicken and camel bones as adsorbents for the removal of Pb2+ and Cd2 from polluted water. The Hydroxyapatite (HA) adsorbents of chicken (HB) and camel (CB) bones were prepared via chemical treatment with NaOH, HNO3, H2O2, and ethanol, and also those followed by carbonization. The physicochemical and microscopic characteristics of the adsorbents were analyzed via SEM, XRD, FT-IR, and BET surface area analyses. Adsorption studies of Pb2+ and Cd2+ were performed in a batch style that included initial metal concentration, pH, pHpzc, solution temperature, contact time, and adsorbent dose. The results revealed that the bone chemically activated with 0.1 M NaOH had greater adsorption of Cd2+ ion (99.7% for HB and 99.89% for CB) and Pb2+ ions (99.85% for HB and 99.79% for CB) than the other activators did. Adsorption isotherms, adsorption kinetics, and thermodynamic models have been used to confirm the fit conditions that improve the adsorption technique. Maximum adsorption removal percentages for Pb2+ and Cd2+ were obtained under constant operation conditions (initial metal concentration 10 ppm, pH 6, adsorbent dose 0.05 g, contact time 30 min and solution temperature 328 K. Adsorption of Pb2+ and Cd2+ obeyed a pseudo-second-order model and fit well with the Langmuir isotherm.The metals adsorption using the prepared adsorbent was a spontaneous and exothermic process. Overall, the prepared adsorbents from chicken and camel bone waste are highly effective and promising as low-cost materials for the remediation of heavy metals-contaminated waters. Article highlights: Low cost hydroxyapatite adsorbents were prepared from chicken and camel bone waste by chemical activation. The prepared adsorbent was used for the removal of Pb and Cd from wastewater. The chemically activated adsorbent with 0.1 M NaOH reveals higher Pb and Cd adsorption [ABSTRACT FROM AUTHOR]

Composite for treatment of Cd2+, Cu2+, Fe2+, Pb2+ and Zn2+ from polluted water was synthesized by chemical activation of waste glass powder (TGP) and activated carbon (AC) using acetic acid, HCl and NaOH. Different AC to TGP ratios (1:1, 2:1, and 1:2 w/w, respectively) were used for the preparation of the composite C(AC/TGP) The composite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET surface measures. The effect of various variables (solution temperature, amount of adsorbent, initial metal concentration, contact time and pH of the solution) on metal adsorption was investigated. The results revealed that the composite C(AC/ TGP)3 with the AC/ TGP ratio (2:1 w/w) was more effective in removing heavy metals than the others. The adsorption efficiency of the metal adsorption increased with the increasing contact time, pH, and adsorbent dosage. Maximum adsorption of the metals was achieved at contact time 30 min, adsorbent dose 1.5 g and pH 7. Adsorption isotherms (Tempkin, Langmuir, D-R, and Freundlich) fitted well to describe the adsorption of the studied metals by composite C(AC/ TGP)3. The kinetic of heavy metal adsorption follows a pseudosecond order pattern. Applying the optimum adsorption parameters of the prepared composite to well water results in 99-100% elimination of the studied heavy metals. [ABSTRACT FROM AUTHOR]

This study aims to incorporate the analysis and interpretation of aeromagnetic data with the results of vertical electrical sounding to investigate the horizontal and vertical extensions of subsurface contaminant plume caused by the wastewater dumpsite at the downstream of Wadi Uranah. It is also the aim of this study to investigate the subsurface geological and structural elements controlling the flow and accumulation of contamination. The results show that the contamination flow and accumulation are controlled mainly by the subsurface faults and basement topography. Subsurface faults form pathways for the contamination, while subsided basement blocks form basins with thick sedimentary cover, suitable for accumulation of the contamination. The southwestern part of the area, close to the Red Sea, is probably affected by seawater intrusion. [ABSTRACT FROM AUTHOR]

This study aims to explore the preparation and application of alum sludge (AS) and mud sludge (MS) from a drinking water treatment plant to remove methylene blue (MB) dye from aqueous solution. The sludge (MS and AS) was treated by chemical and physical activation to obtain new adsorbents. The adsorption experiments were carried out under different conditions of initial dye concentration (50-100 mg/L) adsorbent dosage (0.05-0.25 g), solution pH (3-9), temperature (20-60°C) and contact time (20-90 min). Scanning electron microscopy (SEM) and X-ray diffraction instruments were used for characterization of the developed adsorbents. The results show that sludge activated by nitric acid (0.25 M HNO3) and pyrolysis at 700 °C were the best chemically and physically activated adsorbents. The optimum adsorption conditions for the adsorption of MB are 100 ppm initial dye concentration, 1 hour contact time, 250 °C solution temperature, pH 7 and 0.25 g adsorbent dosage. Application of the Langmuir and Freundlich Isotherm models showed that adsorbents fitted the Langmuir model well. SEM studies indicated the porous structural aspects of sludge suitable for removing MB dye. [ABSTRACT FROM AUTHOR]

Heavy metals are considered among the most important potentially harmful pollutants. Nine heavy metals, Co, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn, were determined in total 192 samples (96 soil, 48 flower, and 48 honey samples), which were collected from polluted areas (Edfu and Kom Omb cities) and unpolluted areas (Esna and Aneeba cities) at Aswan district, Egypt. Metal concentrations were measured using an atomic absorption spectrophotometer. The results revealed that honey in polluted areas showed higher concentrations of Cu, Pb, Fe, and Zn than honey from unpolluted areas. This is related to the pollution input from industry activities in polluted areas. A study of metal concentrations in flowers revealed that flowers contained the highest levels of the studied metals than those in honey. The presence of these metals in plant flowers were correlated with their presence in corresponding honey. Concentration factors of heavy metal for honey/flower in polluted areas seem to be higher than in that of the unpolluted ones. Element concentrations in the honey under study were in the safety baseline levels for human consumption. Results suggested that honey may be useful as an environmental indicator for assessing the presence of environmental pollution with heavy metals. [ABSTRACT FROM AUTHOR]

Lead, one of the earliest metals recognized and used by humans, has a long history of beneficial use. However, it is now recognized as toxic and as posing a widespread threat to humans and wildlife. Treatment of lead from polluted water and wastewater has received a great deal of attention. Adsorption is one of the most common technologies for the treatment of lead-polluted water. This technique was evaluated here, with the goal of identifying innovative, low-cost adsorbent. This study presents experiments undertaken to determine the suitable conditions for the use of peach and apricot stones, produced from food industries as solid waste, as adsorbents for the removal of lead from aqueous solution. Chemical stability of adsorbents, effect of pH, adsorbents dose, adsorption time and equilibrium concentration were studied. The results reveal that adsorption of lead ions onto peach stone was stronger than onto apricot stone up to 3.36% at 3 h adsorption time. Suitable equilibrium time for the adsorption was 3–5 h (% Pb adsorption 93% for apricot and 97.64% for peach). The effective adsorption range for pH in the range was 7–8. Application of Langmuir and Freundlich isotherm models show high adsorption maximum and binding energies for using these adsorbents for the removal of lead ions from contaminated water and wastewater. [ABSTRACT FROM AUTHOR]

Distribution and phase association of Cd, Cr, Cu, Fe, Mn, Ni, Pb, Znand organic matter in Nile sediments taken from Lake Nasser (Aswan, Egypt) were investigated. The sediment samples were subjected to selective chemical extraction procedures designed to fractionate the particulate heavy metals into six fractions: (A) ammonium acetate-extractable metals; (B) sodium acetate-extractable metals; (C) acid oxalate-extractable metals; (D) hydroxylamine HCl-extractable metals; (E) aqua regia-extractable metals and (F) total metals (HF/HCl/HNO3 destruction). Exchangeable metals which can be extracted by ammonium acetate solution are generally considered readily bioavailable as they are weakly bound and may equilibrate easily with the aqueous phases. In the present study very small concentrations of all heavy metals considered were found in this phase. Between this phase and the metal phases which are not bioavailable (those exist in highly resistant phases) there exist several geochemical phases (fractions B, C & D)that may potentially release their associated metals under changing environmental conditions, such as pH and redox potential in the watersediment interface. [ABSTRACT FROM AUTHOR]