Tag Archives: Juan P. Hinestroza

Textiles that clean pollution from air and water

I once read that you could tell what colour would be in style by looking at the river in Milan (Italy). It may or may not still be true in Milan but it seems that the practice of using the river for dumping the fashion industry’s wastewater is still current in at least some parts of the world according to a Nov. 10, 2016 news item on Nanowerk featuring Juan Hinestroza’s work on textiles that clear pollution,

A stark and troubling reality helped spur Juan Hinestroza to what he hopes is an important discovery and a step toward cleaner manufacturing.

Hinestroza, associate professor of fiber science and director of undergraduate studies in the College of Human Ecology [Cornell University], has been to several manufacturing facilities around the globe, and he says that there are some areas of the planet in which he could identify what color is in fashion in New York or Paris by simply looking at the color of a nearby river.

“I saw it with my own eyes; it’s very sad,” he said.

Some of these overseas facilities are dumping waste products from textile dying and other processes directly into the air and waterways, making no attempt to mitigate their product’s effect on the environment.

“There are companies that make a great effort to make things in a clean and responsible manner,” he said, “but there are others that don’t.”

Hinestroza is hopeful that a technique developed at Cornell in conjunction with former Cornell chemistry professor Will Dichtel will help industry clean up its act. The group has shown the ability to infuse cotton with a beta-cyclodextrin (BCD) polymer, which acts as a filtration device that works in both water and air.

A Nov. 10, 2016 Cornell University news release by Tom Fleischman provides more detail about the research,

Cotton fabric was functionalized by making it a participant in the polymerization process. The addition of the fiber to the reaction resulted in a unique polymer grafted to the cotton surface.

“One of the limitations of some super-absorbents is that you need to be able to put them into a substrate that can be easily manufactured,” Hinestroza said. “Fibers are perfect for that – fibers are everywhere.”

Scanning electron microscopy showed that the cotton fibers appeared unchanged after the polymerization reaction. And when tested for uptake of pollutants in water (bisphenol A) and air (styrene), the polymerized fibers showed orders of magnitude greater uptakes than that of untreated cotton fabric or commercial absorbents.

Hinestroza pointed to several positives that should make this functionalized fabric technology attractive to industry.

“We’re compatible with existing textile machinery – you wouldn’t have to do a lot of retooling,” he said. “It works on both air and water, and we proved that we can remove the compounds and reuse the fiber over and over again.”

Hinestroza said the adsorption potential of this patent-pending technique could extend to other materials, and be used for respirator masks and filtration media, explosive detection and even food packaging that would detect when the product has gone bad.

And, of course, he hopes it can play a role in a cleaner, more environmentally responsible industrial practices.

“There’s a lot of pollution generation in the manufacture of textiles,” he said. “It’s just fair that we should maybe use the same textiles to clean the mess that we make.”

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

Cotton Fabric Functionalized with a β-Cyclodextrin Polymer Captures Organic Pollutants from Contaminated Air and Water by Diego M. Alzate-Sánchez†, Brian J. Smith, Alaaeddin Alsbaiee, Juan P. Hinestroza, and William R. Dichtel. Chem. Mater., Article ASAP DOI: 10.1021/acs.chemmater.6b03624 Publication Date (Web): October 24, 2016

Copyright © 2016 American Chemical Society

This paper is open access.

One comment, I’m not sure how this solution will benefit the rivers unless they’re thinking that textile manufacturers will filter their waste water through this new fabric.

There is another researcher working on creating textiles that remove air pollution, Tony Ryan at the University of Sheffield (UK). My latest piece about his (and Helen Storey’s) work is a July 28, 2014 posting featuring a detergent that deposits onto the fabric nanoparticles that will clear air pollution. At the time, China was showing serious interest in the product.

Nano-enabled fique fiber filters harmful dyes from water

A Sept. 30, 2013 news item on ScienceDaily highlights a new technique for cleaning water,

A cheap and simple process using natural fibers embedded with nanoparticles can almost completely rid water of harmful textile dyes in minutes, report Cornell University and Colombian researchers who worked with native Colombian plant fibers.

Dyes, such as indigo blue used to color blue jeans, threaten waterways near textile plants in South America, India and China. Such dyes are toxic, and they discolor the water, thereby reducing light to the water plants, which limits photosynthesis and lowers the oxygen in the water.

The study, published in the August issue of the journal Green Chemistry, describes a proof of principle, but the researchers are testing how effectively their method treats such endocrine-disrupting water pollutants as phenols, pesticides, antibiotics, hormones and phthalates.

The Sept. 30, 2013 Cornell University news release on EurekAlert, which originated the news item,, describes the research in more detail,

The research takes advantage of nano-sized cavities found in cellulose that co-author Juan Hinestroza, Cornell associate professor of fiber science, has previously used to produce nanoparticles inside cotton fibers.

The paper describes the method: Colombian fique plant fibers, commonly used to make coffee bags, are immersed in a solution of sodium permanganate and then treated with ultrasound; as a result, manganese oxide molecules grow in the tiny cellulose cavities. Manganese oxides in the fibers react with the dyes and break them down into non-colored forms.

In the study, the treated fibers removed 99 percent of the dye from water within minutes. Furthermore, the same fibers can be used repeatedly — after eight cycles, the fibers still removed between 97 percent and 99 percent of the dye.

“No expensive or particular starting materials are needed to synthesize the biocomposite,” said Combariza [Marianny Combariza, co-author and researcher at Colombia’s Universidad Industrial de Santander]. “The synthesis can be performed in a basic chemistry lab.”

“This is the first evidence of the effectiveness of this simple technique,” said Hinestroza. “It uses water-based chemistry, and it is easily transferable to real-world situations.”

The researchers are testing their process on other types of pollutants, other fibers and composite materials. “We are working now on developing a low-cost filtering unit prototype to treat polluted waters,” said Combariza. “We are not only focused on manganese oxides, we also work on a variety of materials based on transition metal oxides that show exceptional degradation activity.”

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

Biocomposite of nanostructured MnO2 and fique fibers for efficient dye degradation by Martha L. Chacón-Patiño,a   Cristian Blanco-Tirado, Juan P. Hinestroza, and  Marianny Y. Combariza. Green Chem., 2013,15, 2920-2928 DOI: 10.1039/C3GC40911B First published online 19 Aug 2013

This paper is behind a paywall.

For anyone not familiar with the fique plant,

The native Columbian fique plant, Frucraea Andina. (Credit: Vasyl Kacapyr)

The native Columbian fique plant, Frucraea Andina. (Credit: Vasyl Kacapyr)

I have mentioned Juan Hinestroza and the research he and his students perform on nano-enabled textiles a number of times including this May 15, 2012 posting on anti-malaria textiles.