UV-LED can be used for very low dye degradation ....in the range of 2-25 ppm...higher concentration need higher timer number of UV-LEDyou can see my group papers on UVLED..

http://pubs.acs.org/doi/abs/10.1021/ie9012437,

http://www.sciencedirect.com/science/article/pii/S1385894711002750

http://pubs.acs.org/doi/abs/10.1021/ie200493k

http://www.sciencedirect.com/science/article/pii/S1385894711012460...

The selection of lamp mainly depend on the bandgap of your catalyst in case of TiO2 it is approx 3.2 eV so u can use UV source, however selection of low/medium/high pressure mercury lamp depend upon ur concentration of dye solution. A medium pressure mercury lamp can be used for degradation of 50-200 or higher ppm  of dye. if u have any question. contact me on [email protected]

Hello sir,

Thanks for your reply. Sure, I will mail you queries regarding this.

Regards

Soyab  

I am totally agree with Prof. Tayade Sir. You can follow these points.

You can try with UV-LED lamps. They can provide higher radiant fluxes and the operational costs can be notably reduced  :)

UV-LED can be used for very low dye degradation ....in the range of 2-25 ppm...higher concentration need higher timer number of UV-LEDyou can see my group papers on UVLED..

http://pubs.acs.org/doi/abs/10.1021/ie9012437,

http://www.sciencedirect.com/science/article/pii/S1385894711002750

http://pubs.acs.org/doi/abs/10.1021/ie200493k

http://www.sciencedirect.com/science/article/pii/S1385894711012460...

Dr Rajesh Tayade

Would you have the information about where I can buy those UV-LEDs you used in your papers?

Expose your sample solution in a closed chember to Mecury Lamp . Photo decomposition of the dye sample occurs to get colourless solution.

Kindly inform from where I can buy UV-LED. Is it available on normal Lamp Stores.

My Email: [email protected]

See, all these range of Hg lamps (Low/Medium/High pressure) have different spectral characteristics. Their utility mainly depends on the optical properties of your photocatalyst (preferably the band gap) and scale of operation.

As low pressure Hg lamp used to be of lower wattage (thus, limited to small scale application) and mainly provide UV-C irradiation, which is very suitable for high band-gap photocatalysts like TiO2. In addition, they also offer the bactericidal activity. Low pressure Hg lamps are highly energy efficient.

Whereas, the medium/high pressure Hg lamps cover a wide range of spectral irradiation and have higher wattage (thus, applicable for large scale application), and so provide very high heating effect (that also need to be controlled during the operation).

(Please note that, I am not considering the photosensitization effect of pollutants, here)