Tag Archives: Amir Kabir University of Technology and Institute for Color Science and Technology

Producing cellulose nanoparticles from waste cotton

This nanocellulose item comes courtesy of Iran, from a July 29, 2014 news item on Nanowerk (Note: A link has been removed),

Researchers from Amir Kabir University of Technology succeeded in the synthesis of cellulose nanoparticles by using two environmentally-friendly processes (“Spherical cellulose nanoparticles preparation from waste cotton using a green method”).

The use of waste cotton fibers for the production of cellulose nanoparticles is among the interesting points in this research.

In addition to biodegradability and the ability to be recovered and re-used, cellulose nanoparticles are light and cheap, and they have very desirable mechanical properties. Therefore, they have high potential to be used in pharmaceutics, foodstuff, cosmetics, paper production and composite manufacturing.

A July 29, 2014 Iran Nanotechnology Initiative Council (INIC) news release, which originated the news item, provides more detail about the research,

Dr. Tayyebeh Fattahi Mei-abadi, one of the researchers, explained about the advantages of this method over the usual methods, and said, “In this project, spherical cellulose nanoparticles were produced from waste cotton fibers through enzyme hydrolysis and ultrasound methods. Acidic hydrolysis is usually used in the majority of the researches on the production of cellulose nanoparticles. This method is not in agreement with environmental issues, and it leaves byproducts. But in this research, enzyme hydrolysis method was used, which enables the production of nanoparticles under mild condition without any environmental damage, and it does not require specific equipment. In addition, ultrasonic process was carried out with low energy in a short period, which makes cost-effective the production of cellulose nanoparticles through this method.”

In the production of the nanoparticles, various parts of cellulose enzyme were attached to cellulose chains, and they started to hydrolyze crystalline and amorphous areas. As hydrolysis goes on, particles with average size of 520 nm are formed. Then, ultrasound energy converts the hydrolyzed fibers into nanoparticles at about 70 nm in size.

Here’s a link to and a citation for the paper,

Spherical cellulose nanoparticles preparation from waste cotton using a green method by Tayebeh Fattahi Meyabadi, Fatemeh Dadashian, Gity Mir Mohamad Sadeghi, and Hamid Ebrahimi Zanjani Asl.Powder Technology Volume 261, July 2014, Pages 232–240 DOI: 10.1016/j.powtec.2014.04.039

This paper is behind a paywall.

 

Removing dye from textile wastewater

I remember once reading a fashion article about the rivers in one  of Italy’s major textile centres. Apparently, the rivers were running red as it was that year’s ‘on trend’ colour and that’s what happens when mills empty their wastewater into rivers.  That article came back to mind on reading this Mar. 27, 2013 news item on Nanowerk (Note: A link has been removed),

Researchers at Amir Kabir University of Technology and Institute for Color Science and Technology [Iran] produced a bio-adsorbent with very high performance for the removal of dye from textile wastewater by preparing a combination of chitosan and dendrimer nanostructure (“Dye removal from colored-textile wastewater using chitosan-PPI dendrimer hybrid as a biopolymer: Optimization, kinetic, and isotherm studies”).

Among the unique characteristics of these bio-adsorbents, mention can be made of high adsorption capacity, biodegradability, biocompatibility and non-toxicity.

There’s a March 28, 2013 news release on the Iran Nanotechnology Initiative Council (INIC) website, which provides more detail abut this work,

The aim of the research was to produce chitosan-dendrimer combination in order to remove dye from the wastewater containing reactive dyes. To this end, chitosan was modified in the first step by using ethylacrylate. Then in the second step, chitosan-dendrimer combination was produced by using PPI second generation of dendrimer.

Parameters that affect the dye removal process including pH, concentration of dye, time and temperature of contact were studied by RSM program in order to optimize the process. Kinetic studies and adsorption isotherms at equilibrium were evaluated too in order to measure the amount of dye adsorbed on the adsorbent.

Results showed that chitosan-dendrimer polymer bio-adsorbent could be used as a high potential and biodegradable bio-adsorbent to remove anionic compounds such as reactive dyes from textile industry wastewater. High adsorption capacity, biodegradability, biocompatibility, and non-toxicity are among the unique properties of these adsorbents.

Here’s a citation and a link for the article,

Dye removal from colored-textile wastewater using chitosan-PPI dendrimer hybrid as a biopolymer: Optimization, kinetic, and isotherm studies by Mousa Sadeghi-Kiakhan, Mokhtar Arami1, Kamaladin Gharanjig. Journal of Applied Polymer Science, Volume 127, Issue 4, pages 2607–2619, 15 February 2013. Article first published online: 16 MAY 2012 DOI: 10.1002/app.37615

Copyright © 2012 Wiley Periodicals, Inc.

The article is behind a paywall.

Plus, for anyone (like me) who needs a definition for adsorbent (from the Dictionary of Construction),

A material that has the ability to extract certain substances from gases, liquids, or solids by causing them to adhere to its surface without changing the physical properties of the adsorbent. Activated carbon, silica gel, and activated alumina are materials frequently used for this application.