Experimentally, volatile organic matter is determined after burning at 550oc for half an hour but ash is determined after burning at 550oc for 4 hours, is this true or false?
What kind of samples do you have ? There are different methods depending on the material whether it is coal, soil, sludge...
hi Joachim
thank you for your respond, my samples are anaerobic sludge and industrial wastewater
First step : dry mass at 105 Celsius, than 4 h in a muffle furnace, 550 Celsius. Weight loss by balance and 1 h back to the oven until weight constance is achieved.
Dear Randa,
Dr. Kunze is right.
LOI, %= (Weight 105 - Weight 550)/Weight 105 * 100
Best regards
Just a simple note : We have an experimental part in one of our practical courses that is concerned with the determination of both moisture & V.O.M in soap. The student will weigh say 5 g. of solid soap to the nearest 0.01 g. & then places it in an oven which is set at 103 oC -105 oC for a total of 40 minutes. The residual product is cooled in a desiccator & then weighed quickly. The percentage of the volatiles becomes obvious & the student writes % residue(as total solids) in the lab report.
Hi Randa,
I was interested in your question, because we sometimes need to perform VS analysis in liquid dairy manure.
Liquid dairy manure (especially after storage), contains volatile fatty acids. I am concerned about the impact of volatile fatty acids on the VS estimation (during the First step: dry mass at 105 Celsius).
Since this discussion has been very productive, I am putting this question to get a feedback.
Please excuse for asking another question in your discussion, but I hope it would be useful to everyone.
-SJ.
If Prof. Randa allows me to try to answer Dr. Susantha, I shall say:
In our experiment, mentioned in the above contribution, the volatile organic matter will not include fatty acids because soap is (by defintion) an alkaline salt of long chain fatty acids. The chains will usually contain more than 9 carbon atoms and most often 16-18 carbon atoms. So if there are fatty acids left upon soap production, they are practically nonvolatile.
The volatile fatty acids (within manure & other materials) contain 2 - 8 carbon atoms & therefore they will accompany the other volatiles upon evaporation inside an oven. Since the acids are organic, then they will be included within the V.O.M which means a reduction in the percentage of total residual solids.
By the way, I saw an interesting article close to this subject so I thought of attaching it in the link.
http://www.sciencedirect.com/science/article/pii/S0956053X14003250
Prof. Dr. Nizar
I'm so happy by your kind interest, hope you every thing is going well with you.
your answer is guide for me.
best wishes
have a look on this documents
for most of solid determination
http://www.leco.co.za/wp-content/uploads/2012/02/TGA701_COKE_203-821-381.pdf
regards
Hi everyone,
I want to analyse the % ash content in purification method of humic acid (HA). for that I treat the HA with solution of HF and HCl. After that I shake it for some time and put filtrate in furnace at 800 C for 4 hrs. after this I calculate the weight and find HA as difference in weight. Is it true method?
Thanks
concentrations of humic acid are traditionally estimated out of concentrations of organic matter (typically from concentrations of total organic carbon (TOC). I wonder if your method delivers true data.
Concentration of humic acid are traditionally estimated out of concentations of organic matter. total organic carbon (TOC) determination.
- I wonder if your method delivers true data.
- Badges
- Science topic
- Similar topics
- Linguistics
- Composition Studies
- Publication