Optimisation of a photochemical sensor for total organic carbon measurement.
A new tool for the measurement of TOC based on the heterogeneous photocatalysis activated by two different light sources has been planned. The instrument is constituted by a cell where the degradation occurs thanks to both the UV irradiation and the presence of a powered catalyst and by a measurement cell lodging CO2 gas permeable membrane electrode (detector), thermometer, inlet and outlet ways for the samples. One of the sources has a maximum emission at 254nm, while the other simulates the solar spectrum. A suspension (1 g/L) of titanium dioxide (Degussa P25) has been used to catalyse the process. A magnetic stirrer and a circulating pump avoid the deposition of the catalyst on the bottom of the reactor. The online measurement of produced CO2 was performed on 11 molecules (commercial names: Parachlorophenol, D-Glucose, Acid Blue 29, Atraton, Aspirin, Dimethoate, Aldicarb sulfone, Hydroquinone, (R)-Propranolol, Citric acid, Atrazine) to test the system efficiency. The experimental CO2 value was compared with the theoretical TOC value calculated by means of the structure's formula.
Visco
Giovanni
G
Chemistry Department, Rome University "La Sapienza" P.le Aldo Moro 5, 00185 Roma, Italy. visco@uniroma1.it
Bellanti
Francesco
F
Campanella
Luigi
L
Mazzella
Tommaso
T
Nobili
Valentina
V
D002244:Carbon / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis; D002384:Catalysis; D004566:Electrodes; D004867:Equipment Design; D010777:Photochemistry / Q000295:instrumentation*; D014025:Titanium / Q000737:chemistry
D002245:Carbon Dioxide; C009495:titanium dioxide; D002244:Carbon; D014025:Titanium