Why COD increase after adding PDS for treating wastewater?

• What the possible Persistent Organic Pollutants and Heavy metals present in fluorspar, sediments, and water bodies around its mining area?

Approximate concentrations are require in compared with the WHO permissible limts

11 August 2024 2,723 1 View

Handling Missing Data and Building a Predictive Model with Incomplete Information ?

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Why Do TDS and EC Increase with Larger Wastewater Volumes, While BOD and COD Decrease?

I have carried out MFC experiments on three different volumes, 50, 500 and 1000 mL of wastewater. Results after MFC treatment shows that TDS and EC are more in larger volumes of water i.e. TDS and...

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Do interactions between biosphere, carbon cycle, & water cycle impact global warming & interaction between atmosphere & hydrosphere?

How do interactions between the biosphere, the carbon cycle, and the water cycle impact global warming and interaction between the atmosphere and the hydrosphere?

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Is it true that $\det(V(A))$ may be only $\pm 1$, depending on $n$, for the last symmetric tridiagonal matrix $A$?

One can try to generalize the Vandermonde determinant in the following direction: Let $A$ be any symmetric $n$-order square matrix. Consider its powers' diagonal elements $(A^k)_{ii}$ and...

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How does one derive the standard deviation of a scale?

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Could dyes amplify the spectrum of light to a specific wavelength?

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How to Add Missing Water Molecules in Protein-Membrane Simulations?

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04 August 2024 1,200 2 View

Why results of ROS flurescence are negative as there was no bacteria within?

Hello. I am working on ROS production of two systems: system A is cerium oxide and hydrogen peroxide, system B is cerium oxide nanoparticle, hydrogen peroxide and potassium bromide. I did some...

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Why is nonpoint source pollution potentially more harmful and difference between point and nonpoint sources of water pollution?

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Bachir Achour

What do you mean by PDS or "Peroxedi sulfate"?

Regards

Henrik Rasmus Andersen

I think "Peroxedi sulfate" is another name for persulfate and PDS might abbreviate potassium peroxydisulfate.

The chemical is a peroxide so it can be oxidized by very strong oxidants such as chromic acid which is used in COD analysis. The interference with COD analysis is well known and it is suggested to remove persulfate before the COD analysis.

Article A method for removing persulfate interference in the analysi...

Raghad Mouhamad

change in pH water, so the COD change

Raghad Mouhamad , The COD analysis (Chemical oxygen demand by chromic acid) is not changed by pH of the sample. The analysis is done with a huge excess of sulfuric acid which remove any trace of the sample original pH.