Soil pollution with heavy metals draws a serious concern because of their detrimental effects on the living biota. The persistent and non-biodegradable nature of heavy metals eases their accumulation in the environment. Agricultural soils are receiving tremendous amount of pollutants from the various sources. During the last few decades, rapid urbanization, industrialization, injudicious and fa...

Not all heavy metals are toxic. Some at lower concentrations are essential to the physiological status of the organism. Under certain conditions, induced toxicity occurs when the heavy metals are in the form of cations which tends to bind to certain biomolecules, thus becoming toxic to organisms. In many industries, toxic heavy metals such as As, Cd, Cr, Cu, Hg, Pb and Zn, are released mainly i...

The goal of this study was to determine the removal efficiencies of chromium, copper, lead, nickel, and zinc from raw wastewater by chemically enhanced primary treatment (CEPT) and to attain a total suspended solids removal goal of 80%. Operating parameters and chemical doses were optimized by bench-scale tests. Locally obtained raw wastewater samples were spiked with heavy metal solutions to o...

Adsorption of heavy metals by sawdust was investigated to evaluate the effectiveness of using sawdust to remove heavy metals from aqueous solutions. Kinetic and isotherm studies were carried out by considering the effects of initial concentration and pH. The adsorption isotherms of heavy metals fitted the Langmuir or Freundlich model reasonably well. The adsorption capacity of metal was in the ...

In the recent years, the complexationultrafiltration technique has been shown to be a promising technique for removal of heavy metals in solution. In this study, a polymerenhanced ultrafiltration process has been investigated for removal of toxic heavy metals such as Cu(II), Ni(II), and Cr(III) from synthetic wastewater solutions. Carboxy methyl cellulose as a water-soluble polymer was used for...

Utilization of agricultural waste to produce valuable products has opened opportunities in Egypt to minimize serious public health risks from exposure to dangerous fumes that come from burning the agricultural wastes in open fields. In this study, activated carbon produced locally from cotton stalks was examined for the removal of target heavy metal contaminants from water and wastewater. Adsor...

Given a base design with quantitative factors and a primary linear regression to each of the treatments, we may adjust secondary regressions of linear combinations of the adjusted coefficients on the primary regressions on the factor levels, thus obtaining a biregressional model. A biregressional design was established for a set of treatments, defined from quantitative factors and a linear regr...

The adsorption technique using chemically treated powder of bark of Acacia arabica was applied for the removal of toxic heavy metals from polluted waste water. The extent of adsorption found to be dependent on the pH and the time of contact. The adsorbent is effective for the quantitative removal of various toxic metals from the contaminated aqueous sample. The method is quite feasible, economi...

Polycyclic aromatic hydrocarbons (PAHs), abundant in mixed contaminant sites, often coexist with heavy metals. The fate and remediation of PAHs depend heavily on the sorption and desorption behavior of these contaminants. The sorption behavior can in turn be highly affected by certain soil components and properties, such as soil organic matter (SOM) and the presence of heavy metals. Through rev...

Microorganisms can be important biosorbents for heavy metal remediation of contaminated soils and wastewaters.With different types and concentrations of heavy metals, strains display different resistance and removal abilities to the heavy metals. In the present study, biosorption of Pb(II) was carried out using Aspergillus niger NCIM 616 and also studied the effect of paramaters such as pH, tem...