HKRITA produces superabsorbent polymer from cotton textile waste

Apr 20, 2023

Cotton textile waste collected from HKRITA's Green Machine is being used in a pilot research in India that attempts to develop a genuinely regenerative agricultural process.

An extremely absorbent polymer called Absorboost is being produced as part of a project led by the Hong Kong Research Institute of Textiles and Apparel (HKRITA) and Shahi Exports Pvt Ltd, an Indian garment manufacturer.

This novel breakthrough will aid the apparel and textiles sector by stabilising cotton yields, encouraging textile recycling, and creating an environmentally benign substitute for superabsorbent polymers made of petrochemicals.

According to HKRITA CEO Edwin Keh, the organisation is enthusiastic about the possibilities of this recent discovery.

"We’ve been working on different recycling technologies for a few years. One of these outcomes is the Green Machine. This is our hydrothermal system to separate and reuse blended materials," he said

"Cellulose from this system has been recovered and made into several different materials. One of these is a super absorbent polymer, what we call Absorboost. This material absorbs up to 30 times its weight in moisture and slowly releases it and repeats the process. We thought this may help reduce water use in agriculture and help grow healthier plants," added Keh.

Keh says the team has been running growing experiments to see how this behaves in the real world.

The Green Machine, a hydrothermal technique created by HKRITA and the H&M Foundation, recycles blended fabrics using just heat, water, pressure, and a biodegradable green chemical.

Since it is a closed-loop system and the water, heat, and chemicals are reused again, it is both time and money efficient and produces no secondary pollutants. Long, high-quality polyester fibres are produced, which can be used to create new clothing. The cotton is converted into cellulose powder, which has a variety of applications.

The trial is being held in Karnataka, India, which is the world's top producer of cotton. The team claims that the pilot study's findings can help local agriculture and trade in the future since they are an agricultural tool for ensuring consistent cotton yields and supplies.

Keh explains that because HKRITA had previously worked with Shahi Exports on other projects and was aware of the company's extensive usage of cotton and direct interaction with ginners, working with them on this project felt like a logical choice.

"We sent them some material and asked them to do a small growing test with the Absorboost material to see how well it works or indeed if it works. We were all surprised with the performance and so our growing experiments grew bigger and bigger. Shahi is interested in working directly with farmers to improve their income with this material. They have engaged with an Agricultural University to conduct experiments to validate the results," he said.

In order to explore if they can achieve a fertilizer-free growing process, Keh claims that HKRITA is currently working with second-generation Absorboost with micro nutrients. In the near future, studies of the third generation will be conducted to replenish the soil as well as the cotton with nutrients.

"Our hope is to make a truly regenerative agricultural process," Keh adds. "We are open to work with any party on regenerative agriculture, sustainability, and circularity."