Subject:
Re: I have problem to ask you.
Date:
Thu, 11 Mar 1999 10:58:21 +0000
From:
"Prof. J. F. Scamehorn" <scamehor@ou.edu>
Organization:
University of Oklahoma
To:
suvena somabutr <s_somabutr@hotmail.com>
CC:
Kitipat.S@chula.ac.th, k_thitipong@hotmail.com, bkunchan@pioneer.netserv.chula.ac.th
References:
1


Suvena:

You are taking the entirely wrong approach in your view of the project.
I sent you the dissertation to give you the perspective on the
importance of understanding the adsorption mechanism of surfactant and
calcium in flotation deinking and to see the adsorption isotherms which
Dr. Riviello measured. I just want you to measure these adsorption
isotherms in much more detail that he did since it was a peripheral
issue in his work. The measurement of the equilibrium adsorption
isotherms is the focus of you project. You will not do flotation
experiments. I want you to use the same model inks and paper fibers as
Riviello did.

I am currently in correspondence with Riviello about the analysis
question on the octanoate which I was asked. I had recommended Total
organic carbon because the HPLC technique is quite tricky for that
surfactant. Since it is not difficult for SDS, I suggest that you use
SDS as the surfactant to start with in your measurements. I can't
remember whether you or Thitipong was studying ink and which was
studying fiber. But, the experiments will be the same except for
substrate. One recommendation is that you will want to have as high a
solid to liquid ratio as possible in your adsorption experiments to
maximize the accuracy of the isotherms. You want just enough liquid in
excess to be able to get a sample to analyze for surfactant and calcium
concentrations. Read the papers from the adsorption at the solid/liquid
interface section of the short course notebook for more background on
adsorption. The idea is to understand the mechanism of
surfactant/calcium adsorption on ink and fiber and how they differ on
the two different surfaces and to particularly understand the synergism
in adsorption between surfactant and calcium. Riviello found that the
calcium had much more interaction with octanoate than with SDS and we
want to understand this and the differences in the interaction with the
two different adsorbents.

So, the repeat, you will be measuring adsorption isotherms in you theses
and that of thitipong, not actual flotations.


suvena somabutr wrote:
>
> After I and Thitipong read your dissertation. We have idea to set
> the experiment but we aren't sure that is already correct.
> According to this picture that is shown in this web site;
> http://pioneer.netserv.chula.ac.th/~skitipat/s.html
> . The model equipment for study froth flotation is already have it in
> laboratory.
> -Experiment
> 1. Take pulp and add water to be 1 liter in cylinder.
> 2. add solution of surfactant and calcium, hold it for complete
> adsorption.
> 3. vary the concentration of surfactant and calcium to study.
> 4. Take gas from air compressor to make froth and froth will take ink
> and surfactant to the surface.
> 5. Collect froth and detect concentration of surfactant and calcium
> by HPLC and AA respectively.
>
> -quesiton
> 1. What type of paper(newsprint, Xerox paper or another) that you
> want me to study in research?
> 2. How can I prepare pulp fiber from paper?
> 3. You suggest me to vary many of initial concentration of surfactant
> and calcium in experiment.
> What is more detail of conclusion than your dissertation that you need
> me to study
> (adsorption mechanism that can explain by solid/liquid interface, DLVO
> theory or many that you teach me)?
>
>
> ______________________________________________________
> Get Your Private, Free Email at http://www.hotmail.com

--

********************************************************
John F. Scamehorn
Asahi Glass Chair in Chemical Engineering
Institute for Applied Surfactant Research
School of Chemical Engineering and Materials Science
100 E. Boyd
University of Oklahoma
Norman, Oklahoma 73019

Ph. 405-325-4382
FAX 405-325-5813

e-mail: scamehor@ou.edu

********************************************************