Due to the growing population and oil-dependent industries, the demand for oil products has risen. The increase in oil production, and consequently the higher consumption rate together with the careless use of oil products have aggravated the contamination of water and soil resources, which in turn has led to serious, and sometimes irreparable, harms to the environment. The amount of the leached contaminants, the flow path, the contaminants' traveling time in soil and water resources, and the concentration of pollutants in various depths are the main points the policy-makers need to determine.In this study, the researchers utilized a model called RITZ (Regulatory and Investigative Treatment Zone Model) to model the oil products' leaching into the soil and groundwater resources. This model is used not only to evaluate the leaching process, but it also helps us to locate the contaminated zone and to measure the pollutant's concentration. For the calibration of the model, the output data from the RITZ model were compared with the laboratory data as reported in the previous studies. The obtained high correlations and the other results are shown in different tables and graphs.

Background and Aims: There is concern that leached components from dental composites may cause adverse changes in the reproductive health. This study aimed to assess the effects of leached components from a hybrid resin composite on the reproductive system of male mice.Materials and Methods: In the present animal study, twenty adult Syrian male mice were divided into two groups of 10 mice each. In the test group, components which leached from samples made from Filtek Z250 resin composite into 75% ethanol were daily administered to the mice for 28 days. In the control group, the procedure was repeated in the same way as the test group but without placing composite samples in the solution. Then, the body weight, weights of paired testes, Gonado Somatic Index, sperm viability, sperm motility, epididymal sperm reserve and daily sperm production were recorded. Four male mice in each group were mated with untreated female mice for 10 days. After that, the number of pregnant females and number of infants were recorded. The data were analyzed using repeated measures ANOVA, Chi-square test and t-test.Results: There was a significant reduction in the sperm viability and sperm motility of male mice in the test group compared to the control group (P=0.001). There was no any significant differences in other parameters between two groups (P>0.05).Conclusion: This study showed that the leached components from resin composites cannot cause infertility but they could potentially cause some adverse effects on the reproductive system of male mice.

Background: Tetrabrombisphenol A (TBBPA) is one of the major brominated flame retardants (BFRs) used in waste mobile phone printed circuit boards (WMPPCB) that accounts for approximately 60% of the total BFR market. Methods: The potential of TBBPA removal from WMPPCB leached solution was investigated using micelle-enhanced ultrafiltration (MEUF) in the presence of cationic, anionic, and nonionic surfactants. The efficiency of several parameters including surfactant concentration, transmembrane pressure (TMP), pH, and TBBPA concentration, was evaluated to improve the MEUF. The optimal conditions were used to assess the MEUF for removing TBBPA in a real sample. Results: The cationic surfactant cetylpyridinium chloride (CPC) showed better performance than other surfactants in removing TBBPA due to its electrostatic interactions with anionic forms of TBBPA. The removal efficiency of TBBPA increased from 48. 99% to 99. 10% by adding a surfactant (less than the critical micelle concentration). Increasing the pH in the range of 5 to 11 increased the efficiency of TBBPA removal due to the increase in the TBBPA solubility in the micelles. TMP had the most significant effect on permeate flux compared to other parameters but did not significantly affect the TBBPA removal efficiency. The MEUF process effectively removed (above 99%) TBBPA in the concentration range of 20 to 80 mg L-1 under optimal conditions. The HPLC-UV analysis of the real sample indicated the removal efficiency of 100% of TBBPA. Conclusion: MEUF using CPC is a critical performance technology for removing TBBPA from the leached solution of electronic waste.

Total Dissolved Solids (TDS, mg/L) indicates the amount of soluble salts in water or in a solution, and usually calculates by measuring the electrical conductivity (ECdw, μ S/cm) and then multiplied by 0. 64. This is a general conversion factor (CF) and its amount varies depending on the water-soluble components. In fact, TDS meters determine TDSvalueby measuring of the EC solution and default or user-selected CF. Hence, the precise method is to calculate this coefficient according to the solute type. In this research, to determine precisely the amount of soluble solids along with suspended dust in MDCO sediments traps installed in the north of the Yazd-Ardakan plain. To obtain the TDS calculation coefficient from ECdw resulting from leaching of small amounts of dust, three methods including of an experimental coefficient of 0. 64, physical vapor deposition weighing and measuring the concentration of ions affecting chemical salinity were compared. Comparison of mean of the CFs obtained from the three methods showed that the TDS value of the method of coefficient of 0. 64 for determination of TDS from ECdw, was significantly lower than the other two methods. Hence, applying of this method, leads to a low level of solute content with dust in the study area. The average of the TDS conversion factor obtained by the physical and chemical methods without significant differences were 1. 03 and 0. 90 respectively, compared to 0. 64 in the experimental method, that makes it possible to calculate more precisely the TDS from the measured ECdw data that derived from leached dust, and it can be used to adjust the TDS conversion factor in EC and TDS simultaneous measurement devices.

Mineralogy of oxide zone as clue about past climate reveals occurrence of supergene enrichment processes in Mahour Zn-Cu-(Pb-Bi-Ag) mineralization, in central Lut, during two stages: In first stage that supergene processes have occurred from meteoric waters in an arid climate during Oligocene to Upper Miocene, leached capping contains jarosite, natrojarosite and goetite in various ratios and less hematite and sulfur has formed with supergene argillic alteration with quartz, alunite, kaolinite, montmorilonite, and gypsum. In response to neutrialization of solutions, an abundance of smithsonite and malachite with neotocite, greenokite /hawleite and minor azurite and silicate, phosphate and arsenate minerals precipitated in oxide zone and immature sulfide enrichment generated. In second stage, atachamite, paratacamite and chrysocolla have been formed through the interaction of saline waters and preexisting copper oxides after the onset of hyperaridity at Pliocene, and have been preserved since that time. Mineralogy features of leached capping provide insighs into hypogene ore mineral and alteration types and indicate sufficient acid has not been produced for effective leaching of Cu and hence, do not suggest extensive chalcocite enrichment under water table. An interpretation that mineralogy of oxide zone is also illustrative of it and results from exploration drill holes confirm it. With respect to style of Mahour polymetal mineralization and similar mineralizations in district, detail investigation of oxide zone and mapping leached caps in deposit and district scale can be used as suitable exploration tool in the search for conceal ore deposits.

Leached cappings are limonitic bodies that form due to supergene processes at the top of porphyry copper deposits. According to the formation mechanism of these bodies, one can estimate the caracters of the hypogene porphyry stock and the intensity of supergene effects. These cappings are jarositic, goetitic and hemetitic bodies that dominance  of each cappings, indicate the type and amounts of hypogene sulfide mineralization and supergene enrichment beneath the water table. Sonajil porphyry copper deposit is a porphyry body and demonstrates common hydrothermal alterations such as potassic, phyllic, argillic and propyllitic. Compositionally, sonajil porphyry is diorite, and hypogene minerals such as pyrite, chalcopyrite, bornite, solfosalts (tetrahedrite-tenentite, enargite), Molybdenite, Magnetite and hematite occur as disseminated, micro-veinlets, veinlets and veines. Varous proportions of limonitic minerals formed in these cappings. Predominantly, capping samples are brown in color and they seem to be goetitic. Also, based on chemical analysis, the majority of samples are composed of goetite and jarosite and minor hematite. The presence of goetitic capping is an evidence for lack of development of supergene enrichment and the insufficient amount of pyrite for producing acid responsible for leaching of copper from oxide zone, thus we can't expect high supergene enrichment. The results are verified by bore hole drilling.

The batch removal of copper (II) ions from aqueous solution under different experimental conditions using alkali-leached silica and activated charcoal was investigated in this study. The copper (II) uptake was dependent on varying time, pH, copper concentration and temperature. Copper sorption was found fast reaching equilibrium within 1 h with better performance for alkali-leached silica than charcoal. Copper sorption was low at low pH values and increased with rise in initial pH-value until 6.7. Sorption fits well the Langmuir and Freundlich equations with higher uptake by increasing temperature. According to Langmuir equation, the maximum uptake of Cu(II) ions by alkali-leached SiO2 and charcoal was found to be 242.5 and 94.4 mmol/g at temperature 60 oC and pH 6. Thermodynamic studies confirm that the process was spontaneous and endothermic nature. Kinetic data for Cu (II) sorption was found to follow pseudo-second-order model.

The purpose of this research is to separate iron, arsenic and antimony impurities from zinc silicate ore leach solution using precipitation methods including hydroxide precipitation, by changing pH and reduction precipitation, by changing oxidation/reduction potential. The optimum condition to remove impurities with minimal zinc loss, achieved in the presence of Ca(OH)2, pH = 4.5, temperature of 70°C, in 40 minutes by hydroxide precipitation, and 0.5g/liter of zinc powder, 60°C and 60 minutes by reduction precipitation. In these conditions, most of the main impurities, including 98% iron and arsenic ions, more than 80% of antimony ions and approximately 60.5% of copper ions, were removed. Furthermore, in these conditions, only 5.63% of zinc ions were lost. Therefore, the most part of PLS impurities, were removed before solvent extraction, by performing a successive pre-purification. The results showed that the pH parameter and the precipitant agent had the greatest effect on the precipitation process.

Deep ocean manganese nodules are significant futuristic resource of copper, nickel and cobalt. After recovery of these valuable metals, a huge quantity of residue (~70 % of ore body) is generated. In the present paper, investigations carried out for the application of washed manganese nodule leaching residue (wMNR) for the removal of nickel (Ni) ions from aqueous solution by adsorption are described. Several parameters have been varied to study the feasibility of usingwMNR as potential adsorbent for remediation of Ni (II)-contaminated water. The adsorption kinetics followed pseudo-first-order equation, and the rate of adsorption increased with solution temperature. Kinetics data of Ni (II) adsorption were also discussed using diffusion models of Webber-Morris and Dumwald-Wagner models. The equilibrium data were best fitted into Langmuir adsorption isotherm, and the maximum adsorption capacity was found to be 15.15 mg g-1 at pH 5.5 and temperature 303 K, which decreased to 10.64 mg g-1 upon raising the solution temperature to 323 K. The activation energy for Ni (II) adsorption onto wMNR was 9.56 kJ mol-1 indicated physical sorption. Desorption studies showed successful regeneration of adsorbent and recovery of Ni. This process can be utilized for removal and recovery of Ni from the industrial effluent.