Hi!

Yes, its so important if you are trying to analyze them with AAS.

Regards

Yes, because wastewaters, depending on the source, contain apprecible levels of organics which will definitely interfere with the determination of heavy metals, especially using AAS

You can analyze heavy metals using AAS without digestion, but...... there are implications:

1. The debris both soluble and non soluble solutes in the wastewater will block essential parts of the instrument;

2. The principle of AAS is based on absorbance (remember Beer-Lambert law), so interference will render your analysis null and void;

3. Digestion will purify your sample, while refusing to digest samples will spoil the whole effort on sampling.

Yes digestion is must for analyzing samples in AAS, digestion will dissolve all impurities present in sample and you may get accurate result

Yes, it is extremely important if you are interested in the total amount of heavy metals, a some are bound to organic/inorganic matrices which should be digested in order to release the bound metals as soluble ions.

Yes it is important in order to increase the sensitivity of metal detection by AAS.

Yes it is advised.  First you will obtain complete quantity off analysable heavy metals in your samples (total amounts). And moreover you must use standard solutions for calibration made with the same acide at the same concentration that in your sample (homogeneity). Choice of acide dépends of type of sample but for waste waters, nitric acid is generazlly usd. All the best.

Very important. Some of the metals you wish to determine could be bound in organic matrices. Digestion is the procedure that breaks the matrices and releases them into the aqueous phase for spectroscopy determination. Why wouldn't you use ICP OES?

I endorse Mr. Joseph's resonse

Yes, it is necessary to digest wastewater sample before analysis of heavy metal.

100 ml is minimum sample volume required for acid digestion.

90ml of water + 10ml of nitric acid. Heat to about quarter of original volume. And make it up to 100ml using std flask

Yes it is essential to digest & concentrate before going to analysis on AAS

What is the procedure for acid digestion of petrochemical refinery wastewater for heavy metal analysis.

Should we digest our acidic wastewater for heavy metals analysis by using ICP? The pH of the wastewater sample is already below 2. Can we analyses directly without digestion?

Yes, You have to digest wastewater before ICP analysis, because digesting breakdown complex metal form into an ionic forms which can be detect by Instrument. Another, lower pH reduce the precipitation of metal ions in the solution, So lower pH help as preservatives.

Thanks

What is the procedure for acid digestion of wastewater for heavy metal analysis by using ICP. Please elaborate the digestion procedure. Thanks