Summary for spent sulfuric acid analysis Discussion
analysis of spent sulfuric acid is discussed mainly as a practical lab problem: Jayesh Ruparelia asked how to identify inorganic impurities in spent acid from the dyes industry, where strength ranges from 40–60% and likely contaminants include sodium sulfate and sodium chloride. Jarett Burgett suggested first digesting 10 mL of sample by heating it to dense white fumes, then carefully adding 30% hydrogen peroxide to clear the solution, diluting to volume, and testing chloride by ion chromatography or silver nitrate titration. He said sodium could be measured on the digest by AA or ICP, but that determining sulfate would not be practical. In a later exchange, K A Chaudhary asked about organic impurities, and Daniel Montañés replied that the answer depends on which organic family is of interest and asked for more specific information before recommending a method. The thread ends without a detailed organic-matter method.
Q. I want to do analysis of spent sulfuric acid, which is outcome of dyes industry. Strength of acid varies between 40-60% and impurities may be organic or inorganic. I am interested to know inorganic impurities. Major contributors may be sodium sulphate and sodium chloride.
Jayesh Ruparelia
Education – Mumbai, Maharashtra, INDIA
2003
A. Try heating 10 mL the spent sample in 150mL beaker [beakers on
eBay
or
Amazon [affil link] with a matching watch glass on a hotplate until it reaches dense white fumes. Then, remove it from the hotplate, remove watch glass and allow it to cool down until there fumes are gone. Replace the watch glass and SLOWLY AND VERY CAREFULLY drip 30% hydrogen peroxide down the side of the beaker until the sample clears. Quantitatively transfer the mixture to a 1 liter volumetric flask and dilute to the mark with water. Analyze the sample for chloride using ion chromatography or titration with silver nitrate. It would be not be practical to determine sulphate in the sample. Sodium can be ran on the digest via AA or ICP.
Jarett Burgett
Aircraft – Wichita, Kansas, USA
2003
Q. I want to do analysis of spent sulfuric acid, which is outcome of chemical industry. Strength of acid varies between 20-60% and impurities may be organic or inorganic. I am interested to know organic impurities.
K A Chaudhary
Education – Gandhidham, Gujarat, INDIA
December 7, 2012
? Dear Mr. Chaudhary,
Do you mind telling us what kind of organic impurities are you looking for? There are some methods for organic compounds, but every method has some chemical family it measures.
If you can specify, we may be able to help you. Best regards,
Daniel Montañés
– Cañuelas, Buenos Aires, Argentina
December 11, 2012
⇦ Tip: Readers like to learn from others’ situations;
some readers skip abstract questions.
Q. METHOD OF ORGANIC MATTER IN DEMINERALIZED WATER
K A CHAUDHARY [returning]
– GANDHIDHAM, GUJARAT, INDIA
January 12, 2013
A. Hi cousin Chaudary. You cut & pasted your first question, and I don’t know if this is an answer Daniel’s request for clarification or if you just blew him off and are now asking another question. Such minimal effort on your own behalf — an all-caps, punctuation-free, 7-word fragment — while asking all the readers struggle to try to understand you, doesn’t seem to justify a stranger putting in much effort for you :-)
Thanks for your understanding!
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
January 17, 2013
Thank you for your answer to my earlier query.
Q. My new question is regarding demineralised water plant. We want to analyse organic matter in outlet water sample from Activated Carbon Filter (ACF).
K A CHAUDHARY [returning]
– GANDHIDHAM, GUJARAT
January 17, 2013
A. There’s two things you could do with your DI water; send it out to a lab and have them run Total Organic Carbon (TOC) or get yourself a Chemical Oxygen Demand (COD) set up. The latter may not be sensitive enough. But, if it suits you, Hach Co. sells a good one.
Dave Wichern
Consultant – The Bronx, New York
February 14, 2013
 | April 4, 2013 ⇦ Tip: Readers like to learn from others’ situations; Q. I want to know the standard method (conventional) of determination of NOx (NO + NO2) in low pressure BOILER Stack. We are using FURNACE OIL as a fuel having 3.0 % sulfur & 10 % Carbon Residue. K A CHAUDHARY [returning] ⇦ Tip: Readers like to learn from others’ situations; Q. Please mention the flame temperature while the fuel is used as a furnace oil and combustion with air. K A Chaudhary [returning] ⇦ Tip: Readers like to learn from others’ situations; Q. WHAT WILL BE EFFECT IF CALCIUM CARBONATE IS INCREASED FROM 2.0% TO 5.0% IN POLY PROPYLENE BAGS. K A CHAUDHARY [returning] ⇦ Tip: Readers like to learn from others’ situations; Q. I WOULD LIKE TO KNOW THE EFFECT OF CALCIUM CARBONATE ON POLYPROPYLENE FABRIC AND ALSO SUGGEST THE RATIO OF CALCIUM CARBONATE & POLYPROPYLENE FABRIC WHICH GIVES HIGHER BREAKING STRENGTH. K A CHAUDHARY [returning] |
Q. I want to do analysis of spent sulfuric acid, which is outcome of chemical industry. Strength of acid varies between 25-30% and impurities may be organic or inorganic. I am interested to know organic impurities. Can I analyse by COD method? It is possible or not?
HAWALDAR SALIM
EDUCATION – MUMBAI, MAHARASHTRA, INDIA
March 26, 2020 — apologies; slipped thru the cracks til July 3
A. Hello Hawaldar
The best way to analyze for organics is by TOC (total organic carbon analysis). The TOC-L series – catalytic combustion system along with a high salt kit.
To my knowledge the COD method is mainly used for determining organic matter in water using an oxidizer such as potassium dichromate. I have my doubts that you could get accurate readings in a 25% Sulfuric using the COD method, and the dangers of using a strong oxidizer for determination. Hope this helps.
Mark Baker
– Winston Salem, North Carolina USA
July 4, 2020