What is the possible mechanism for decay of organic pollutants under sole PMS/dark process?

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Grzegorz Boczkaj Popular answer

The PMS can directly oxidize some organic compounds. It can also decompose forming active species like sulfate radicals. The radicals formation takes place mainly in the presence of PMS activators. It can be activated by (HO-) ions. You can read this papers on this topic:

Article Chemistry of persulfates in water and wastewater treatment: A review

Article Application of peroxymonosulfate and its activation methods ...

Article Wastewater treatment by means of advanced oxidation processe...

Article Wastewater treatment by means of Advanced Oxidation Processe...

regards,

Luma M. Ahmed

Hello,

The effect of pH in dark reaction can be active to degrade the organic pollution that depended on the structures of these pollutants and if you used any catalyst? that will give a easy mechanism.

Amal Abdelhaleem

Dear Luma

I really appreciate your help. Thanks so much. However, I just used PMS in dark and no catalyst is included. This happens only at specific pH values not for all pH range.

Regards,

Grzegorz Boczkaj

Dear Dr. Boczkaj

Thanks so much for your favorable reply. It happens at pH 2.4 and pH10. I do not know how the radicals can be generated in dark without activators. Regards,

The temperature was 23 C for all pH values. However, it works only at those two pH values.

Regards

Yang Lei

check this publication：http://pubs.rsc.org/-/content/articlelanding/2016/ra/c5ra19718j/unauth#!divAbstract

You will find the answer.

Dear Yang

Thanks so much. I am wondering that this happens at two pH values only. Do you have any explanation for that? I think I need to check LC/MS in this process, Right?

In addition, my compound is neutral and does not hold cationic charge.

Zacharias Frontistis

Check also this publication

Influence of pH on persulfate oxidation of TCE at ambient temperatures

Chengdu Qi

check this publication：Article Activation of peroxymonosulfate by base: Implications for th...

PMS can be activated to generate ROS at pH > 9.

Renli Yin

PMS can selectively decompose some organic pollutants without any activation. Additionally, the pKa of H2SO5 should be noticed for the different pH condition. You can check the following file.