background & aims of the study: tea is one of the most important beverages that consumes in several parts of the world including iran. tea plant can be contaminated during manufacturing processes and growth period by pollutants such as heavy metals. in this study, the concentration of some heavy metals in different brands of both iranian and imported black tea to iran was investigated to survey...

One of the most paramount processes that play a considerable role in reducing the concentration of heavy metals during estuarine mixing is flocculation. Not only does such a process cause a huge percentage of metals to come into the particulate phase, but also it provides ample nutrients for the aquatic life. In the present study, impact of such factors as salinity, pH and DO on flocculation of...

The adsorption of benzene on the M(111), M(100) and M(110) surfaces of the coinage metals copper (M = Cu), silver (M = Ag) and gold (M = Au) is studied on the basis of density functional theory (DFT) calculations with an empirical dispersion correction (D3). Variants of the Perdew-Burke-Ernzerhof functionals (PBE, RPBE and RevPBE) in combination with different versions of the dispersion correct...

To study Pseudomonas putida CZ1, having high tolerance to copper and zinc on the removal of toxic metals from aqueous solutions, the biosorption of Cu(II) and Zn(II) by living and nonliving P. putida CZ1 were studied as functions of reaction time, initial pH of the solution and metal concentration. It was found that the optimum pH for Zn(II) removal by living and nonliving cells was 5.0, while ...

The study was carried out on the sorption of heavy metals (Ni2+, Cu2+, Pb2+, and Cd2+) under static conditions from single- and multicomponent aqueous solutions by raw and pretreated clinoptilolite. The sorption has an ion-exchange nature and consists of three stages, i.e., the adsorption on the surface of microcrystals, the inversion stage, and the moderate adsorption in the interior of the mi...

The chemical speciation of heavy metals (arsenic, chromium, copper, lead, zinc and tin) in the sediments of former tin mining catchment Bestari Jaya, Peninsular Malaysia was determined by using the latest version of the Community Bureau of Reference, usually called the BCR 3-step sequential extraction procedure. Furthermore, a fourth step was introduced for digestion and analysis of the residue...

Cow bone charcoal (CBC) was synthesized and used for the removal of metals ions (manganese, iron, nickel and copper) from aqueous solutions. Two different adsorption models were used for analyzing the data. Adsorption capacities were determined: copper ions exhibit the greatest adsorption on cow bone charcoal because of their size and pH conditions. Adsorption capacity varies as a function of p...

the pollution of water environments is a challenging issue especially in developing countries. contamination of drinking water with heavy metals has been reported in many parts of the world. arsenic, chromium and lead are dangerous heavy metals and also common contaminants of drinking water. in this study, the capacity and performance of the surfactant-modified sabzevar natural nanozeolite (sms...