Environmental Engineering Reference
In-Depth Information
Air humidity in the experiments was about 40% at a temperature of 32°C. Test results have shown that the concentration of
DDT on the surface of the slab decreased to 0.1-0.2 g/m
2
in 3 days.
11.5
conclusions
Colloidal solutions of electrochemically synthesized NCMC (Ti) have shown a high efficiency as photocatalysts for the destruc-
tion of chloroorganic substances such as aldrin, lindane, DDT, and PCBs. Photodegradation occurs within the NCMC (Ti)
concentration range of 1 µg/l to 10 mg/l. The time for degradation of aldrin, lindane, and PCBs dissolved in water under the UV
lamp and sunlight is about 5-7 h. Trichlorobenzenes are formed as reaction products during the first 2 h of irradiation of lindane,
but are completely destroyed 3 h after the start of the irradiation process. The concentrations of organic reaction products in the
photodegradation process of aldrin, DDT, and PCBs were lower than the detection limit. The destruction time of powders of
aldrin, lindane, and DDT is about 8-10 h. The concentration of DDT sprayed on the concrete slab surface decreased from 1-2
to 0.1-0.2 g/m
2
in 3 days. In the near future, for decontamination of soil, we are going to develop an apparatus that continuously
stirs the soil samples and irradiates them by sunlight or UV.
references
[1] Khaydarov RA, Khaydarov RR, Gapurova O. water purification from metal ions using carbon nanoparticle-conjugated polymer nano-
composites. water Research 2010;44:1927-1933.
[2] Tang wZ, An h. UV/TiO
2
photocatalytic oxidation of commercial dyes in aqueous solutions. Chemosphere 1995;31:4157-4171.
[3] Kim SB, hwang hT, hong SC. Photocatalytic degradation of volatile organic compounds at the gas-solid interface of a TiO
2
photocata-
lyst. Chemosphere 2002;48 (4):437-444.
[4] Kim SB, Cha wS, hong SC. Photocatalytic degradation of gas-phase methanol and toluene using thin-film TiO
2
photocatalyst. II.
kinetic study for the effect of initial concentration and photon flux. Journal of Industrial and Engineering Chemistry 2002;8
(2):162-167.
[5] Abu Bakar wAw, Othman R, Ali My. Photocatalytic degradation and reaction pathway studies of chlorinated hydrocarbons in gaseous
phase. Transactions C: Chemistry and Chemical Engineering 2010;17 (1):1-14.
[6] Jiang D, Zhao h, Zhang S, John R. Comparition of photocatalytic degradation kinetic characteristics of different organic compounds at
anatase TiO
2
nanoporous film electrodes. Journal of Photochemistry and Photobiology A Chemistry 2006;177 (2-3):253-260.
[7] Sopyan I. An efficient TiO
2
thin-film photocatalyst: photocatalytic properties in gas-phase acetaldehyde degradation. Journal of
Photochemistry and Photobiology A Chemistry 1996;98 (1-2):79-86.
[8] yu h, Zhang K, Rossi C. Theoretical study on photocatalytic oxidation of VOCs using nano-TiO
2
photocatalyst. Journal of Photochemistry
and Photobiology A: Chemistry 2007;188:65-73.
[9] Oki K, Tsuchida S, Nishikiori h, Tanaka N, fujii T. Photocatalytic degradation of chlorinated ethenes. International Journal of
Photoenergy 2003;5:11-15.
[10] Bryan CS, Michael Ow. Metal nanoparticle—conjugated polymer nanocomposites. Chemical Communications 2005;27:3375-3384.
[11] Daniel M-C, Astruc D. Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications
toward biology, catalysis, and nanotechnology. Chemical Reviews 2004;104:293-346.
[12] Rao CNR, Cheetham AK. Science and technology of nanomaterials: current status and future prospects. Journal of Materials Chemistry
2001;11:2887-2894.
[13] Schmid G, Simon U. Gold nanoparticles: assembly and electrical properties in 1-3 dimensions. Chemical Communications
2005;6:697-710.
[14] Tan y, Li y, Zhu D. Synthesis of poly (2-methoxyaniline)/Au nanoparticles in aqueous solution with chlorauric acid as the oxidant.
Synthetic Metals 2003;847:135-136.
[15] Mulvaney P. Not all that's gold does glitter. MRS Bulletin 2001;26:1009-1014.
[16] Murphy CJ, Jana NR. Controlling the aspect ratio of inorganic nanorods and nanowires. Advanced Materials 2002;14:80-82.
[17] Khlebtsov NG, Trachuk LA, Mel'nikov AG. Sensitivity of metal nanoparticle surface plasmon resonance to the dielectric environment.
Optika i Spectrosk 2005;98:77-86.
[18] Mock JJ, Smith DR, Schultz S. Interparticle coupling effects on plasmon resonances of nanogold particles. Nano Letters
2003;3:1087-1090.
[19] hsu wK, Terrones M, hare JP, Terrones h, Kroto hw, walton DRM. Electrolytic formation of carbon nanostructures. Chemical Physics
Letters 1996;262:161-166.
