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Showing 3 results for Afkhami
Hexavalent Chromium Removal from Rqueous Solution by Produced Iron Nanoparticles
A Rahmani, R Norozi, M.t Samadi, A Afkhami,
Volume 1, Issue 2 (10 2009)
Abstract

Background and Objectives:Groundwater treatment by nano particles has received increasing interest in recent years. Chromium is a commonly identified contaminant in soils and groundwater. Zero-valent iron, as a natural reduction agent can be used in controlling of contaminated sites. The aim of this research is investigation of hexavalent chromium removal from aqueous solutions by using of iron nano particles the effective parameters. Materials and Methods: In this research the synthesized of the iron nano particles has performed by addition of NaBH4 to FeCl3·6H2O solution and Cr(VI) reduction efficiency in Batch system was studied. Also the impact of the important field parameters including pH, initial chromium concentration, nano zero valent iron concentration and retention time were investigated.
Results:The results of this research showed that synthesized particles were in nano scale. In pH=3, chromium inlet concentration of 10 mg L-1, nano zero valent iron concentration 0.5 g L-1 and 2 minute retention time, 100% of Cr(VI) was removed.
Conclusion:The concentration of nano zero valent iron had significant effect on the reduction of Cr(VI).The reaction occurred in a wide range of pH value and the reaction efficiency increased significantly with decreasing initial pH. The significant removal efficiency, high rate of process and short reaction time were showed that iron nano particles have significant potential in removal ofCr(VI) from contaminated water.


Feasibility study of using Calcium Peroxide  Nanoparticles in Arsenic Removal from Polluted Water in Agriculture and It's Effect on the Irrigation Quality Parameters 
Ehsan Olyaie, Hossein Banejad, Ali Reza Rahmani, Abbas Afkhami, Javad Khodaveisi,
Volume 5, Issue 3 (21 2012)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Arsenic is one of the most toxically contaminants in groundwater and soils. Due to the ability of bio-accumulation of arsenic III in plants through irrigation with contaminated water and its entrance to the food chain, irreparable hazards would be caused. The aim of this research is the feasibility study of arsenic III removal from polluted water using calcium peroxide nanoparticles synthesized and also studying the effective parameters. Moreover, the adding effect of nanoparticles on the important parameters of irrigation would be assessed.
Materials and Methods: In this research, we first synthesized CaO2 nanoparticles through chemical precipitation and then studied the arsenic removal efficiency from contaminated water samples. Nevertheless, the impact of the effective parameters including pH, initial arsenic III concentration, and CaO2 nanoparticles concentration were investigated. Finally, relevant results to nanoparticles effect on the important irrigation water quality parameters were presented.
Results: Our results showed that synthesized particles were in the range of 25-50 nanometers. In addition, the efficiency of the CaO2 nanoparticles in arsenic III removal was 88 percent under following conditions:  irrigation pH range 6.5-8.5, nanoparticles dosage 40 mg/L, arsenic initial concentration 400 µg/L, and 30 minuts retention time. Moreover, the nanoparticles synthesized did not have any undesirable impact on significant parameters in irrigation water.
Conclusion: Generally, it can be concluded that CaO2 nanoparticles based on the in situ chemical oxidation had significant effect on the reduction of arsenic III until lower than recommended standards for irrigation water. High rate of process and relatively short reaction time, and having no negative effects on the significant parameters of irrigation indicate that CaO2 nanoparticles have significant potential in removal of arsenic III from contaminated water.


Effect of irrigation with treated wastewater on lead and cadmium accumulations in soil and sweet pepper plant
Maliha Afkhami, Fazel Amiri, Tayebeh Tabatabaie,
Volume 14, Issue 1 (5-2021)
Abstract
Background and Objective: Limited water resources in arid and semi-arid regions are one of the major limiting factors in agricultural production. Thus, unconventional water resources, such as urban treated wastewater, may be used for irrigation. Application of wastewater to the soil may cause accumulation of heavy metals (HMs). Soil pollution causes uptake of these metals by plants and their entrance to the food chain. In the present greenhouse research, concentration variations of HMs (lead (Pb) and cadmium (Cd)( in soil and sweet pepper (Capsicum annuum) plant were investigated.
Materials and Methods: The experiment was conducted as a completely randomized design with three replications and irrigation with different wastewater treated (well water, wastewater treatment and diluted wastewater). To evaluate the effects of different irrigation treatments on soil, parameters of acidity (pH), electrical conductivity (EC), the concentration of heavy metals Pb and Cd in soil were studied.  Additionally, for the effects of irrigation treatments on sweet pepper plant, parameters of biomass weight, fresh and dry weight and Pb and Cd concentrations (in branches, fruits and roots) were measured. The amount of Pb and Cd in the pepper were measured by ICP-OES. The obtained average concentrations were compared using one-way analysis of variance (ANOVA), and the Duncan test was used to determine the differences between groups (p <0.05). The independent t-test was also used to investigate the difference in concentrations of Pb and Cd in soil and water (p <0.05).
Results: The results of chemical analysis of soil and pepper showed that irrigation with wastewater did not cause a significant increase in the concentration of Pb and Cd in the soil and in the branches, fruits and roots of the pepper. The concentration of Pb and Cd in the soil and in the branches, fruits and roots of the pepper was within the allowable and standard concentration range. The difference in lead and cadmium concentrations in the soil before planting was not significant; however, at the end of the study period, the Pb concentration in pepper was higher than the Cd concentration. The use of wastewater increased the fresh and dry weight of branches, fruits and roots of the pepper.
Conclusion: The results showed that Pb and Cd concentration in roots and aerial parts of pepper plant was not increased significantly as a result of wastewater irrigation (p <0.05). The results of this study are limited to one growing season and by the continued use of municipal wastewater, the concentration of Pb and Cd in the soil and then in the plant may exceed the standard. Especially in the case of Pb, which seems to have shown a slight tendency to increase relative to the primary soil and the pepper. Therefore, the continuation of this study is recommended to evaluate the long-term effects of Bushehr municipal treated wastewater on the concentration of heavy elements in soil and plants, and soil properties. Overall, it should be acknowledged that based on technical recommendations, the use of treated wastewater are not recommended.

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