[cyril]

Hello,

I am trying to make some transmission and reflection measurement of ice sample with an integrating sphere attached to an UV/Vis spectrometer.
The problem is that I don't have any reflection standard, so I want to use some BaSO4 powder. But I can't find any information on how to prepare a standard with this powder.
Can I just fill a cell with some powder and use it like this?

If anyone has any advice on this, it will be very welcome...

Thanks for any help

Cyril

[kevins]

I suggest to add known amount of soluble sulphate solution (e.g. sodium sulphate solution) to the DI water and then add some BaCl2 solution. A known amount of BaSO4 is ppt. I think it is better than add powder to the solution.

[FatihTaskiran]

I have a problem about sod?um sulfate. I have sodyum sulfat w?th ?nclude the water and I would l?ke to throw up that but my sulfat concentration ?s h?gher than legal one
How can I do about this and if I use BaCl2, can I get BaSO4 but not solu?ble only unsol?able

[kevins]

Do you mean you want to remove or lower the sulfate before discharge?

Please use the Calcium Chloride to ppt as CaSO4 instead of Barium Chloride because Ca is non-toxic and cheaper.

[Borek]

Please use the Calcium Chloride to ppt as CaSO4 instead of Barium Chloride because Ca is non-toxic and cheaper.

pK_so BaSO₄ = 10.0
pK_so CaSO₄ = 4.6

[kevins]

Agree, Ba is better than Ca to remove the sulfate. Below is from Wikipedia for Ba salt.

"Precautions
All water or acid soluble barium compounds are extremely poisonous. At low doses, barium acts as a muscle stimulant, while higher doses affect the nervous system, causing cardiac irregularities, tremors, weakness, anxiety, dyspnea and paralysis. This may be due to its ability to block potassium ion channels which are critical to the proper function of the nervous system."


As from the industrical point of view, the treament cost and toxicity of chemicals are the main choice. If the main aim is to lower the sulfate concentration in the effluent before discharge to the river or sea, Ca is the first choice.