I have done FTIR for Rice husk biochar prepared at 3000C and 4000C... I found out that a broad/wide peak at 3428.90 cm-1 for 3000 C and the peak tends to linearity at 4000 C. Also I have found a broad and blunt peak at 1099.43 cm-1 for 3000 C which became narrow and sharp at 4000 C. What dose these results indicates??
The broad peak at ~3400 cm-1 is OH in general (including H2O). Possibly it is remaining carbohydrate OH here, which gets lost at higher temperatures. The peak at ~1100 cm-1 very likely derives from carbohydrate C-O single bonds. Again, progressing carbonization likely removes oxygen.
Did you consider comparing your spectra with the spectra of the original rice husk?
In addition to the Thomas Fischer reply. You consider to compare the spectrum of rice husk at room temperature with the spectra recorded at high temperature. You gradually increase the temperature an then compare the changes. However, broad peaks are due to overlapping of different vibrations. In case of H2O peaks are very broad that will disappear after heating.
The broad peak in higher frequnces refer to H2O molequles or Hydrogen bonding . and also the Carboxylic group too.
Dear Adhraa.... The methodology you've used is not clear. What is the 3000C and 4000 C? Is it degree Celsius? or something else. Charring of rice husks may exhibit high purity silica. There is no possibility to get peaks at the 3400 cm range. This could only be a result of humidity.
Thomas Fischer thank you so much, No, i haven't compared with raw rice husk yet... I will definitely do that.
Mahmood M. Barbooti First of all that question is not put by Adraaa Alfatlawy but by me. And in my question it is clearly mentioned that i have charred the rice husk in 300 degree Celsius and 400 degree Celsius. Yes you are right, the broad peak might be because of water...
the board peak at 3428.90 cm-1 refer to H2O molecules and the peak at 1099.43 cm-1 refer to the C-O group. progressing carbonization at temperature greater than 300C and releases combustible gas and tar
The broad peak at ~3400 cm-1 is due to OH in H2O generally. If you are using as KBr palate, It should be dry under IR lamp before analysis to remove all moisture. Background spectra (empty compartment) should be taken before sample analysis. Apart from that broad peak at -3400 cm-1 indicates hydrogen bonded -OH, however sharp peak at -3400 cm-1 appeared due to free -OH.
- Badges
- Science topic