ΕΘΝΙΚΟ ΜΕΤΣΟΒΙΟ ΠΟΛΥΤΕΧΝΕΙΟ

Finally, the washing of any glass device used was made in three stages : firstly
with deionized water, then with acetone and finally with ultra-pure water. After
washing the glass devices were put for one day in furnace at 106 o C for drying.
Figure 2 : Solid phase extraction apparatus (left) with columns (right).
Results and Discussion
First batch experiment
The first batch experiment was conducted with the system working in parallel
at several GAC bed depths. The concentrations of the EC’s were 1 μg/L and the total
flow was 6,55 L/h. The purpose of this batch experiment was to find proper
parameters, so that the next batch experiments would be ended with proper results in a
reasonable amount of time. The results from this batch experiment did not clearly
show any column breakthrough at any EC, but it clearly showed that GAC effectively
adsorbs all the ECs examined.
Second batch experiment
The second batch experiment was conducted with the system working in series
with 0,20 m GAC bed depth at each column. The concentrations of the EC’s were
2 μg/L and the linear flow rate of the solution was 3,13 m/h. The results from this
batch experiment clearly showed breakthrough of all EC’s at column A.
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