Pomegranate peels were used to remove zinc, chromium and nickel from industrial wastewater. Three forms of these peels (fresh, dried small pieces and powder) were tested under some environmental factors such as pH, temperature and contact time.
The obtained results showed that these peels are capable of removing zinc, chromium and nickel ions at significant capacities. The powder of the peels had the highest capability in bioremoving all zinc, chromium and nickel ions while dried peels had the lowest capacity again for all metals under test. However, the highest capacities were found in a sequence of chromium, nickel and zinc. Furthermore, all these data were significantly (LSD peel forms = 2.761 mg/l, LSD metal ions = 1.756 mg/l) varied.
In case of chromium, these figures were 69.7 ± 0.9 mg/l, 58.0 ± 2.4 mg/l and 49.7 ± 0.5 mg/l for powder, fresh and dried peels respectively. Regarding nickel ions, the data were 58.7 ± 1.1 mg/l for peel powder, 50.7 ± 2.0 mg/l for fresh peel and 42.0 ± 1.2 mg/l for dry peel. While for zinc ions, the biosorption capacity was 48.4 ± 2.2 mg/l, 39.4 ± 0.8 mg/l and 32.0 ± 1.6 mg/l for powder, fresh and dry peels respectively.
However, some examined factors were found to have significant impacts upon bioremoval capacity of pomegranate peels such as pH, temperature, and contact time where best biosorption capacities were found at pH 4, with temperature 50 Cº and contact time of 1 hour.
Regarding pH, the highest bioremoval ability was found at pH 4 for all heavy metals, but with the sequence of Cr, Ni, and Zn and the data were 68.1 ± 1.5 mg/l, 56.0 ± 0.5 mg/l and 47.88 ± 1.21 mg/l respectively. Similar pattern of bioremoval capacity was detected for temperature which was 50 Cº giving capacities of 72.0 ± 0.0 mg Cr/l, 60.0 ± 1.84 mg Ni/l and 54.0 ± 1.72 mg Zn/l. In case of contact time, these capacities were again similar to those of pH and temperature and found to be 76.0 ± 3.0 mg/l , 64.0 ± 1.82 mg/l and 60.0 ± 2.0 mg/l for Cr, Ni, and Zn respectively but at 1 hour contact time.
In this study, phytoplankton density, chlorophyll-a, and selected physico- chemical parameters were investigated in Erbil wastewater channel. The surveys were carried out monthly from May 2003 to April 2004. Samplings were established on three sites from headwaters to the mouth. The results showed that pH was in alkaline side of neutrality, with significant differences (P<0.05) between sites 1 and 3. TSS concentration decreased from site 1 toward site 2 (mean value, 80.15 to 25.79 mg.l-1). A clear gradual increase in mineral content (TDS) observed from site one of the channel towards the mouthpart. Soluble reactive phosphate has a concentration maximum mean value reached 48.4 µg.l-1 which is recorded in site 2. A high positive relat
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Flavonoid-metal complexes from the medicinal plant, Chromolaena Odorata were synthesized in this study using a standard method. Flavonoid extracts complexes, namely Mn-flavonoid complex, Co-flavonoid complex, Zn-flavonoid complex, and Cd-flavonoid complex were characterized using Fourier-Transform Infrared spectroscopy technique (FT-IR). Based on IR data, it was observed that the complexes shifted to lower frequencieswhen compared with the extract, indicating the interaction of the C=O and O-H groups during the complex formation. It was observed that the complexes were synthesized at a certain condition, which is acidic,with pH values ranging from 2.11 to 3.68. The conductance values (Λm) of the complexes were fou
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n the present work, a study is carried out to remove chromium (III) from
aqueous solution by: activated charcoal , attapulgite and date palm leaflet powder
(pinnae). The effect of various parameters such as contact time, and temperature has
been studied. The isotherm equilibrium data were well fitted by Freundlich and
Langmuir isotherm models. The adsorption capacity of chromium (III) that was
observed by activated charcoal , attapulgite and date palm leaflet powder (pinnae)
increased with the rise of temperature when the concentrations of Cr (III) were 600,
700 and 100mg/L respectively. The greatest adsorption capacity ofactivated
charcoal , attapulgite and date palm leaflet powder (pinnae) at 10°C was 7.51, 5.3
The present work deals with an experimental investigation of charging and discharging processes in thermal storage system using a phase change material PCM. Paraffin wax was used as the PCM which is formed in spherical capsules and packed in a cylindrical packed column which acted as an energy storage system. Air was used as the heat transfer fluid HTF in thermal storage unit. The effect of flow rate and inlet temperature of HTF on the time of charging and discharging process were studied. The results showed that the faster storage of thermal energy can be made by high flow rate of heat transfer fluid HTF and high inlet temperature of heat transfer fluid. It was found that at 65°C HTF inlet temperature, the melting and solidification pr
... Show MoreIn this work, varying compositions of SiO2 micro filler were added
with the Polyvinyl Chloride (PVC) and samples have been prepared
using film casting technique. The results have been analyzed and
compared for PVC samples with (1 wt%, 3 wt%, 5 wt% and 10 wt%)
SiO2 micro filler. Mechanical characteristics such as tensile strength,
elongation at break and Young`s modulus were measured for all the
samples, where the tensile strength was increased from 8.39 Mpa for
purified PVC to 16 Mpa for 3% SiO2/PVC composite. Also, thermal
conductivity measurement values illustrated that composite materials
have a good thermal insulation at 10 wt. %, thermal conductivity was
decreased from 0.1684 W/m.
Background: The best material for dental implants is polyetherketoneketone (PEKK). However, this substance is neither osteoinductive nor osteoconductive, preventing direct bone apposition. Modifying the PEKK with bioactive elements like strontium hydroxyapatite is one method to overcome this (Sr-HA). Due to the technique's capacity to provide better control over the coating's properties, RF magnetron sputtering has been found to be a particularly useful technique for deposition. Materials and methods : With specific sputtering conditions, the RF magnetron technique was employed to provide a homogeneous and thin coating on Polyetherketoneketone substrates.. the coatings were characterized by Contact angle, adhesion test, X-ray
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Background: The best material for dental implants is polyetherketoneketone (PEKK). However, this substance is neither osteoinductive nor osteoconductive, preventing direct bone apposition. Modifying the PEKK with bioactive elements like strontium hydroxyapatite is one method to overcome this (Sr-HA). Due to the technique's capacity to provide better control over the coating's properties, RF magnetron sputtering has been found to be a particularly useful technique for deposition.
Materials and methods : With specific sputtering conditions, the RF magnetron technique was employed to provide a homogeneous and thin coating on Polyetherketoneketone substrates.. the coatings were characterized by Contact angle, adhesion test, X-ray dif
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A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat metho
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The removal of direct blue 71 dye from a prepared wastewater was studied employing batch electrocoagulation (EC) cell. The electrodes of aluminum were used. The influence of process variables which include initial pH (2.0-12.0), wastewater conductivity (0.8 -12.57) mS/cm , initial dye concentration (30 -210) mg/L, electrolysis time (3-12) min, current density (10-50) mA/cm2 were studied in order to maximize the color removal from wastewater. Experimental results showed that the color removal yield increases with increasing pH until pH 6.0 after that it decreased with increasing pH. The color removal increased with increasing current density, wastewater conductivity, electrolysis time, and decreased with increasing the concen
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