Tuesday, January 10, 2012

Between methanol and ethanol?


Assalamualaikum...


Dalam dilema. Tak tahu nak pilih solvent mana yang terbaik as cosolvent in SFE extraction. Between 70% methanol and 70% ethanol. Based on preliminary test, seems like 70% methanol is better compared to other solvents. Jom, menilai bersama-sama mistulip. Hehehe.

1. Extraction result: 70% methanol produced higher yield of extract but not much different if compared to 70% ethanol.

Methanol win - 1:0

2. Antioxidant result: From the 3 assays that have been conducted, 70% methanol showed the best antioxidant capability but still not much different if compared to 70% ethanol.

Methanol win again - 2:0

3. Aldehyde detection:  Previous study by Saliza (2007) showed that three types of aldehyde have been detected in 50% ethanol (decanal, undecanal, dodecanal) and only two aldehydes have been detected in 80% methanol (decanal and dodecanal).

Ethanol win - 2:1

---> Saliza is actually a research assistant of Dr Masturah, my supervisor. The point is, the percentage of solvent that she used was obviously different from mine. So???? Need to consider this point.

4. Safety: Ethanol is a food grade solvent, so it is safe to use in food application but not for methanol.

Ethanol win once again - 2:2

5. Cost: Methanol is cheaper than ethanol.

Methanol completely win: 3:2

The winner!

---> Walaupun nak beli chemical bukannya guna duit sendiri, tapi kalau boleh jimat, jimat la kan. Kesian Dr banyak pulak duit geran dia habis nanti. Huhuhu...


So, mana satu pilihan hati? Mistulip rasa, stick dengan 70% methanol la. Sebabnya, lebih baik kita nilai dari segi performance. Walaupun ethanol detect lebih 1 aldehyde banding dengan methanol, tapi percentage yang Saliza guna tu lain berbanding yang mistulip guna. Jadi point tu agak tak boleh diterima sebab composition extract yang guna solvent berbeza peratusan  sepastinya berbeza. One more thing, although ethanol is a food grade solvent, but this research of mine is conducted in lab scale to optimize the SFE parameter only. More on optimization of operating parameter rather than application on food. Lain la kalau dah establish, nak guna untuk industri sangat penting la guna food grade solvent kan.

Ok, it is decided. I chose 70% methanol as the cosolvent to use in SFE extraction. So, dah boleh buat design expert to identify the 3 dominant parameter from 4 available parameter. Mistulip kena run 9 kali SFE extraction ikut design yang kat bawah ni.

Cuba cari perkataan momo. Hahaha...

Lepas semua tempat kosong tu berisi dengan result experiment, boleh la run analysis. Agak-agaknya parameter mana yang akan disingkirkan? Hahaha. Macam program realiti pulak. Harap-harap lancar la semua ni walaupun mistulip tahu nak run SFE 9 kali bukan satu perkara mudah. Huhuhu...




mistulip: No more dilemma. =)

4 comments:

Salman said...

Hi.. klu nk buat solubility studies, ok klu guna 100% methanol, dlm around 5% and 10% ratio. tp kn ingat utk increase kan critical temp..

BTW, awk guna 70%MeOH and 30% water ke? sbb sy dh try bila add water kat solvent, modifier pump susah nk pump..
Apepun all da best with ur research.. Dr Masturah is a good supervisortraldshe

mistulip said...

Guna 100% methanol, yield dpt ckt sgt..so far 70% yang plg optimum..sy nk extract compound untuk check antioxidant n antibacterial capability bg kesum tu..

A'ah 70% MeOH n 30% water...mmg ada mslh ckit ms extraction process,kdg2 blocking...tp mmg cabaran bt sfe mcm tu..ni salman yang bt sfe kat cni dl ke?

Salman said...

Yes, yg buat kt ukm dulu, skrng buat kt utm, kami baru je beli satu unit.. BTW, awak guna 4 factor kan? tp apesal run skit sgt? guna factorial biasa, box behnken or ccd?

mistulip said...

ckit sbb ni br nk decide parameter mana yg dominan..dari 4 nk kurangkan kpd 3...dh tau 3 parameter dominan tu br run yg sbtl2nya..stkt ni gn factorial biasa dl..