We have very good experience with the citric acid applied in common Fenton´s oxidation of various organic pollutants, not photo-Fenton.

Regards

Vit

Article Organics removal and in-situ granule activated carbon regene...

Hi my group did a process called FBR-Fenton/GAC process which is run at pH 3. what we also found is that this process can be run at slightly higher pH without the use of any additional chemical additive. Although the pH range we observed was till ph 4.5. Beyond that pH, the performance of the reactor actually decreases. And at higher pH the reaction rate is much slower, as heterogenous Fenton reaction would start to become more prevalent. FBR-Fenton has the ability to utilise both Homogeous and heterogenous reactions effectively.

Article Activated carbon as carrier in fluidized bed reactor for Fen...

This effect was also reported by another group of researchers. For Photo-Fenton, commonly used iron complex for circumvented pH conditions are mainly: EDDS.

Photo-Fenton process such as a 3-phased Photo fenton is a potential compromise between pH and catalyst used. This uses UV to assists with the regeneration of ferric iron and also promote further radical generation. Reported pH operation of such systems is at pH 5. Do take a look at my group's recent publication on the mechanisms of this system.

Article Fluidized-bed Fenton technologies for recalcitrant industria...

Hope this helps cheers!

In the paper, "Heterogeneous photo–Fenton treatment for degradation of indigo carmine dye ". Cosme-Torres, et al., MRS Advances © 2019 Materials Research Society DOI: 10.1557/adv.2019.451 . 23 de febrero 2020. https://www.cambridge.org/core/terms,

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Question is not a perfect way.Electrical double layer porus.

It will be suction by vacuum pump and porus material.It can be done by manufacturer of glass centered crucible.