heavy metals
Removal of Cadmium from Contaminated Waters Using Saltbush (Atriplex Canescens) Biomass: Identification of Cd Binding Sites
Tue, 2015-02-10 10:55 — Maather SawalhaThe effect of pH on Cd(II) binding capacity of saltbush biomass was determined. Metal quantification performed using ICP/OES showed that Cd binding increased as pH increased from 2.0 to 5.0. The highest percentage of Cd bound ranged from 74-81%, 22-40%, and 70-80% for the native, esterified, and hydrolysed biomass. XAS studies showed that cadmium was present as Cd(II) and oxygen was the nearest neighbouring atom with bond lengths of approximately 2.3 Å and coordination numbers ranging between 4 and 5. Results indicated that carboxyl groups may be the primary ligand involved in the Cd binding by saltbush biomass.
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Physicochemical Characterization of Olive Oil Mill Wastewaters In The Eastern Region of Morocco
Thu, 2014-10-09 13:40 — Shehdeh JodehThe aim of this study is to achieve a complete
physicochemical characterization of the samples of the olive oil mill wastewaters
collected from five different prefectures in eastern Morocco (Oujda, Nador,
Berkane, Taourirt and Jerada), A comparative study was investigated with
several OOMW samples from three olive oil extraction processes (traditional,
semi-modern and continuous) were compared. This research is one of the first
studies investigating the physicochemical characterization of olive oil mill wastewaters oil mills crushing olives Oujda
area. The composition of OOMW varies significantly for each mill. The results
of the physicochemical analyzes showed that all the samples of olive oil mill
wastewaters have an acidic pH, the average value is between (4.5 and 5.32); and
the values of the conductivity are varied between: 23-41ms/ cm for the (PP and
CP3P) but for the (CP2P) are varied between: 13-25 ms/cm, this high
conductivity due to the addition of the salt during storage before their
crushing olives. The OOMWs are rich in organic matter. This last parameter is
expressed as BOD5
and COD. The average of the total BOD, COD, biodegradability, of samples varied
with oil extraction processes, for the (PP): (BOD5 : 17-25 g O2 5 /L; COD
:108-120 g O/L; biodegradability: 0.11-0.25); for the (CP3P): (BOD5: 12.5- 23 gO2/L; COD :76-100; biodegradability: 0.16-0.23) and
for the (CP2P): (BOD5: 8.5-19 gO2/L;COD :52-64 g O2 2 /L; biodegradability:
0.16-0.23). And the samples are riche of the Oxidizable matters
((COD+2BOD)/3),therefore, the connecting this industrial facility to a
municipal sewer system is impossible; because, any connection of the units
trituration olives can lead to dysfunctional treatment plant wastewater; but
which poses a great problem for these unit s trituration effluents is
non-biodegradable material: polyphenols and tannins, the values( the samples of
OOMW filtered) are varied: (polyphenols: 0.8-1.35 g/L and tannins :0.62-1.2
g/L) for the PP, for CP3P (polyphenols: 0.29-1.83 g/L and tannins :0.2-1.71 g/L), but for the (CP2P) are varied between (polyphenols:
0.24-0.67g/L and tannins :0.12-0.65 g/L). In this article, recent and older
research studies for the physicochemical characterization of olive mill
wastewaters performed by several authors were shown.
Impacts of Irrigation With Water Containing Heavy Metals on Soil And Groundwater – a Simulation Study
Tue, 2014-05-06 14:02 — Marwan N. HaddadThis research work intended to study the impacts of irrigation water containing various levels of copper, lead, and zinc on adsorption capacity of soil packed in 4[1][1] plastic columns and obtained from two locations around the city of Nablus: Salem (A) and Deir Sharaf (B). Results of simulation experiments showed an increase in the copper, lead, and zinc concentrations in soil and in leachate with increasing the amount of metal in irrigation water. Copper, lead, and zinc concentrations increased also with soil depth and duration of application. The results also indicate that the self purification of both soils was highly affected by physical factors, i.e. the intermittent application of irrigation water to the soils in the columns caused soil wetting and drying cycles which resulted in the formation of cracks in shrinked soils specially in the top half of the columns. Crack formation is common in such clay soils due to the climatic conditions (Mediterranean type: dry summers and wet winters) and type of clay minerals in the soil. Thus, short circuiting of water through cracks results in moving contaminants fast and deep in the soil profile.
Impacts of Irrigation with Water Containing Heavy Metals on Soil and Groundwater – a Simulation Study
Thu, 2014-01-09 13:37 — Mohammed Al-Subu'This research work intended to study the impacts of irrigation water containing various levels of copper, lead, and zinc on adsorption capacity of soil packed in 4′′ plastic columns and obtained from two locations around the city of Nablus: Salem (A) and Deir Sharaf (B). Results of simulation experiments showed an increase in the copper, lead, and zinc concentrations in soil and in leachate with increasing the amount of metal in irrigation water. Copper, lead, and zinc concentrations increased also with soil depth and duration of application. The results also indicate that the self purification of both soils was highly affected by physical factors, i.e. the intermittent application of irrigation water to the soils in the columns caused soil wetting and drying cycles whichresulted in the formation of cracks in shrinked soils specially in the top half of the columns. Crack formation is common in such clay soils due to the climatic conditions (Mediterranean type: dry summers and wet winters) and type of clay minerals in the soil. Thus, short circuiting of water through cracks results in moving contaminants fast and deep in the soil profile.
Impacts of Irrigation With Water Containing Heavy Metals on Soil And Groundwater – a Simulation Study
Sun, 2011-05-15 10:51 — Numan MizyedThis research work intended to study the impacts of irrigation water containing various levels of copper, lead, and zinc on adsorption capacity of soil packed in 4[1][1] plastic columns and obtained from two locations around the city of Nablus: Salem (A) and Deir Sharaf (B). Results of simulation experiments showed an increase in the copper, lead, and zinc concentrations in soil and in leachate with increasing the amount of metal in irrigation water. Copper, lead, and zinc concentrations increased also with soil depth and duration of application. The results also indicate that the self purification of both soils was highly affected by physical factors, i.e. the intermittent application of irrigation water to the soils in the columns caused soil wetting and drying cycles which resulted in the formation of cracks in shrinked soils specially in the top half of the columns. Crack formation is common in such clay soils due to the climatic conditions (Mediterranean type: dry summers and wet winters) and type of clay minerals in the soil. Thus, short circuiting of water through cracks results in moving contaminants fast and deep in the soil profile.
