Actinometry potassium ferrioxalate

A = 253.7nm Parabolic cylinder. Made of Aluminum, specularly finished Measured by actinometry (potassium ferrioxalate) (13.9-5.45-2.33) x 10 Einstein cm s ... 

Incident radiation at the wall Operation Measured by actinometry (potassium ferrioxalate) 100% (without filters) 7.55 X 10 Einstein cm s (at each window) Calculated with a superficial emission model... 

The output of a lamp may be monitored by chemical actinometry. The standard method remains the irradiation of potassium ferrioxalate which is useful in the range 254 to 480 nm. The method is described in detail by Calvert and Pitts (1966) and by Murov (1973). But perhaps, the most convenient way to check the lamp output is to keep a stock solution of a model compound or the reagent itself, if it is readily available, and determine its rate of photolysis periodically by irradiation in a spectrophotometer cuvet. In this way the output of the lamp in the region of interest can be rapidly checked. An alternative is to use one of many radiation measuring instruments that are commercially available, a thermopile and voltmeter, for example (see Appendix for a list of manufacturers). 

Light intensities were measured by potassium ferrioxalate actinometry (51). 

Y. Quan, S. Pehkonen, and M.B. Ray, Evaluation of three different lamp emission models using novel application of potassium ferrioxalate actinometry, Ind. Eng. Chem. Res. 43, 948-955 (2004). 

The exciting light was furnished by an irradiator composed of a 500-W xenon or 450-W high pressure mercury lamp as the light source and filters. The irradiation for the measurement of the quantum yields was performed with a JASCO CRM-FM spectroirradiator composed of a 2000-W xenon lamp as the light source and a grating monochromator. The light intensity was measured by potassium ferrioxalate actinometry [20], and the actinometric estimates were checked with an Eppley thermopile. 

An alternative approach is to use chemical actinometry. A chemical actinome-ter makes use of a photochemical reaction that has an accurately known and easily reproducible quantum yield. One such chemical actinometer uses a solution of potassium ferrioxalate in 0.1 M sulfuric acid. Irradiation of this oxygen-ffee... 

Chemical actinometry has the advantage over physical methods in that the actinometer can be irradiated under conditions similar to those of the photoreaction to be studied [1762]. This eliminates the need to make corrections due to reflectance and nonuniformity of the incident light beam. The liquid-liquid phase chemical actinometer traditionally used is the potassium ferrioxalate system, but it requires the careful preparation of standard solutions and of a calibration graph before measurements can be made [299, 920]. 

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