Mohammad Hadi Abolhasani; Niloofar Pirestani; Ali Eslami
Abstract
Abstract Background and Aim: Increasing levels of toxic heavy metals in the environment have led to risks to the health of humans and living organisms. Materials and methods: First, some characteristics of rock wool including pH, EC, pHZPC, chemical composition, structure, and morphology were determined ...
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Abstract Background and Aim: Increasing levels of toxic heavy metals in the environment have led to risks to the health of humans and living organisms. Materials and methods: First, some characteristics of rock wool including pH, EC, pHZPC, chemical composition, structure, and morphology were determined using XRD, XRF, and Scanning Electron Microscopy (SEM). Adsorbing tests were then conducted in a non-continuous reactor using synthetic solutions containing nickel. Optimum adsorption conditions were determined concerning pH, metal initial concentration, contact time, and adsorbent dose. The data were analyzed in a completely randomized block design. Results: The highest adsorption was seen at pH = 5 and the lowest at pH = 3, with a significant difference. The absorption rate was significantly higher in the 5 mg/l solutions than in other concentrations and the lowest was observed at 100 mg/l concentration. The lowest nickel adsorption rate was observed in 5 min and the highest adsorption efficiency was observed in 90 min, with a significant difference. The adsorption percentage of rock wool waste at the 10 g/l doses was significantly higher than that in other adsorbent doses and the lowest adsorption percentage was observed at the 1 g/l dose. The isotherm studies showed that the adsorption of nickel by rock wool waste was consistent with the Freundlich model. Conclusion: It can be concluded that rock wool waste could remove nickel from industrial effluents.
Mohammad Hadi Abolhasani; Niloofar Pirestani; Parinaz Ahmadi
Abstract
Background and Aim: Petroleum products such as crude oil, gasoline and gasoline are the most commonly used in the world, the major pollutants of water. About 10 million tons of oil are burnt annually in the world. Therefore, the development of new technologies for the elimination and purification of ...
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Background and Aim: Petroleum products such as crude oil, gasoline and gasoline are the most commonly used in the world, the major pollutants of water. About 10 million tons of oil are burnt annually in the world. Therefore, the development of new technologies for the elimination and purification of oil pollution is essential. There are several methods for cleaning up oil pollution and its derivatives. In this research, straw and chalk absorber was used as an organic adsorbent to remove diesel oil from wastewater. Materials and method: The straw and chalk were firstly determined using the FT-IR analysis. Then the adsorption experiments were performed discontinuously using diesel oil laboratory solutions. Optimum adsorption conditions were obtained by changing the factors affecting adsorption including pH, initial concentration of contaminant, contact time and adsorbent amount on adsorption at different levels, The oil absorption was determined by weighting method. Ultimately, the use of adsorbent for laboratory wastewater was studied. Results: The highest absorbent efficiency at the time of equilibrium was observed for absorbing oil using straw and chalk absorber in 15 minutes, which did not have a significant difference with other contact times (49.85% absorbance, p < 0.05) and the lowest value was observed without a significant difference in 3 minutes (37.19% absorption). The effect of straw absorbent values in 2 g/L was significantly higher than other amount of adsorbents (51.48% absorption, p < 0.05) and the lowest percentage of adsorption was significantly different from other values in 0.25 And 0.5 grams per liter (38.30%, p < 0.05). The fitting of Isotherm showed that the adsorption of diesel oil by straw and chalk with both Freundwich and Langmuir models were consistent with the high R2 (R2 = 0.99 and R2 = 0.96).
mohammad hadi abolhasani; niloofar pirestani; hajar amini
Abstract
Background and aim: water oil contamination has occurred in Iran since the previous century and environmental oil accumulation threatens the country water resources’ health. There are several methods to remove oil and its derivatives contamination. In the present study, mineral wool waste was used ...
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Background and aim: water oil contamination has occurred in Iran since the previous century and environmental oil accumulation threatens the country water resources’ health. There are several methods to remove oil and its derivatives contamination. In the present study, mineral wool waste was used as low price adsorbent for wastewater oil contamination (kerosene) removal. Materials and methods: first, XRF and XRD analyses were used to determine chemical composition. Then, adsorption tests were conducted discontinuously using laboratory solutions containing oil to determine optimum adsorption conditions by adjustment of effective factors such as pH, initial concentration, exposure time and adsorbent concentration. Thereafter, application of adsorbent for laboratory wastewater was studied. Results: after 15 min exposure, the adsorbent (mineral wool wastes) efficacy was significantly higher than the other times (76.01 % adsorption; P<0.05); whereas, the lowest efficacy was observed after 3 min (63.82 %; P<0.05). Among the tested pH, the highest and lowest adsorption were observed at pH = 3 (70.59 %; P<0.05) and 9 (57.69 %; P<0.05), respectively. There was no significant difference in adsorption between the adsorbent concentrations of 0.5 and 1 g (76.80 and 75.30 %); however, both were significantly (P<0.05) higher than the other concentrations. the lowest adsorption was observed at the concentration of 0.25 g adsorbent (67.78 %). Isotherm fitting of surface adsorption showed that oil adsorption by mineral wool wastes follows Langmuir model (R2=0.99). Conclusion: it is concluded that mineral wool waste has high efficiency to adsorb oil from wastewater and could be used for oil contamination removal.