mesophilic aerobic, optionally anaerobic microorganisms and grams of negative
bacteria (Escherichia (or E. coli), Citrobacter, Enterobacter or Klebsiella).
Table 3 Results of research on water purification by developed sorbent
Parameter
Initial
value
After treatment with
Required by
Directive
98/83/EC
Zr-Al
Zr-Al-Ag
0
Zr-Al-Ag/Au
Total solids (mg/dm
3
)
1324
922
897
918
1000
Manganese (μg/dm
3
)
67
50
<5
<6
50
Colony count 22°C,
(number/100 ml)
130
92
37
38
100
Coliform bacteria
(number/100 ml)
8
3
0
0
0
Ag
+
(μg/dm
3
)
0
0
15
14
50
Phyto-synthesis of monometallic and bimetallic nanoparticles. Researchers in
nanotechnology are turning towards ‘Nature’ to provide inspiration, for exciting and
innovative methods of nanosynthesis. Synthesizing novel nanoparticles based on the
concept of green nanotechnology is gaining momentum. Green nanotechnology
integrates the principles of green chemistry and green engineering to produce eco-
friendly, safe, nanoparticles that do not use toxic chemicals in their synthesis protocol.
On the other hand, waste management represents an important challenge in the agri-
food based industries. It demands an integrated approach in the context of recycling,
reuse and recovery. Grapes (Vitis vinifera L.) is one of the world’s largest fruit crop
with a global production of 68 million tonnes (2009) of which, 38 million tonnes is
processed. Annually around to 2.5 million tonnes of grape waste is generated. This
huge challenge in the management of grape waste must be addressed [1, 2].
Materials and methods. Grape pomace extract was prepared by macerating in
water by plasma discharge for 5 min at solid: extraction agent ratio of 1g:40 mL water
and filtered through ordinary filter paper. For synthesis of silver nanoparticles, the
Erlenmeyer flask containing 40 ml of AgNO
3
, HAuCl
4
(0.5 g/L) or mixture precursors
was reacted with 40 ml of the aqueous extract of Grape pomace. This setup was
incubated in dark (to minimize the photoactivation of silver nitrate), at 37 ◦C under
static condition. A control setup was also maintained without A. indica extract.
In
synthesizing Ag/Cu bimetallic nanoparticles, silver and copper salts were mixed
together in the ratio of 1:2.
In a typical reaction, AgNO
3
was dispersed in 6 cm
3
of
aqueous extract, followed by CuCl
2
under magnetic stirring with the formation of a
black homogenous colloidal dispersion.
Results and discussion. Monometallic and bimetallic nanoparticles were
prepared by a low-cost, rapid, simple and eco-friendly approach using Grape fruit
extract treated by plasma discharge as a novel natural reducing and stabilizing agent.
The results indicated that the synthesized monometallic and bimetallic nanoparticles
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