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23 November 2021 | Story Leonie Bolleurs | Photo Tania Allen
Dr Jana Vermaas and Ketshepileone Matlhoko are working on research that leaves your washing clean and fresh without the use of any detergents, which is also beneficial to the environment.

Cold water or hot water? Omo or Skip? Laundry blues is a reality in most households and when you add stains to the equation, then what was supposed to be part of your weekly household routine, becomes frustrating and time consuming. 

Researchers at the University of the Free State (UFS) are conducting research that is putting a whole new environmentally friendly spin on laundry day.

Sustainability and environmental conservation

Dr Jana Vermaas, Lecturer in the Department of Sustainable Food Systems and Development at the UFS, is passionate about textiles and sustainability – almost a decade ago, she conducted a study on the efficacy of anolyte as a disinfectant for textiles.

She describes the process: “During electrochemical activation, a dilute solution of natrium chloride/salt passes through a cylindrical electrolytic cell where the anodic and cathodic chambers are separated. Two separate streams of electrochemically activated water are produced. Anolyte as water was produced at the positive electrode and has a low pH, high oxidation-reduction potential and contains dissolved chloride, oxygen, and hydroxyl radical. It also has an antimicrobial effect.”

The benefits of this process are in line with her enthusiasm for environmental conservation. 

According to Dr Vermaas, the amount of water and chemicals used to clean textile articles is massive. “Chemicals used to disinfect, for example, hospital laundry, are hazardous. Not all laundries in the industry have a closed loop system or try to remove the chemicals before the wastewater is discarded.”

“Different amounts of detergents have various effects on our fauna and flora. Due to their low biodegradability, toxicity, and high absorbance of particles, detergents can reduce the natural water quality, cause pH changes in soil and water, lead to eutrophication (too many nutrients), reduce light transmission, and increase salinity in water sources.”

“But with the catholyte and anolyte process, water returns to its original status, which means that the water solution becomes inactive again after production where it existed in a metastable state while containing many free radicals and a variety of molecules for 48 hours. Thus, no chemicals are left in the wastewater. The water can therefore be recycled, not as potable water but, for example, to flush toilets or to water plants.

“We should do what we can to save water,” she says. 

Should you, like Dr Vermaas, also feel strongly about protecting the environment and want to obtain one of these machines that leaves your washing clean and fresh without the use of any detergents, you will be able to find such an appliance in South Arica. However, it does not come cheap. “It is a bit costly for residential use, but might be more accessible in the future,” states Dr Vermaas, who is of the opinion that it is a more sustainable option for commercial laundries.

Detergency properties and colourfastness 

Recently, more research has been conducted on this topic, but with a focus on the detergency properties of the catholyte to clean different textile fibres (natural and synthetic). Catholyte, she explains, is water produced at the negative electrode with a high pH, low oxidation-reduction potential, containing alkaline minerals. It also has surface active agents that increase the wetting properties, and it is an antioxidant. 

“A master’s student in the department, Ketshepileone Matlhoko, will be submitting her dissertation at the end of November on the possibility of using the catholyte as a scouring agent to clean raw wool,” says Dr Vermaas. 

The department is also conducting studies to investigate the influence of both catholyte and anolyte on colourfastness.

*Graphic: Production of electrolysed water (Nakae and Indaba, 2000). Diagram: Supplied



News Archive

How to interpret Centlec’s load shedding
2008-01-31

Everyone in South Africa is affected by power failures (load shedding). Centlec took certain measures to manage the situation. These measures are explained:

Time slots
See the following table for an indication of times when load shedding might be applied to specific areas:  http://www.centlec.co.za/power_shed/PDF/time_slots.pdf

Groups
The city was divided into six groups. This document clearly indicates which area in the city resorts under which group: http://www.centlec.co.za/power_shed/PDF/groups.pdf

According to the document, the university resorts under group 4. In the table with time slots it is the grey area.

Stages
Eskom developed three stages for load shedding. (See stage table at the bottom of the page http://www.centlec.co.za/power_shed/PDF/time_slots.pdf)
- Stage 1: Less load shedding is applied in stage 1. E.g. the UFS resorts in group 4 and on a Monday, according to stage 1, the power will not be switched off during 12:00 and 14:30 (this time slot is not highlighted in orange).
- Stage 2: More load shedding is applied in stage 2. Load shedding will be applied during stage 2 between 12:00 and 14:30 on a Monday at the UFS.
- Stage 3: All time slots are highlighted in orange, which indicates that power will be switched off for the whole duration of stage 3.

Example
Today, Tuesday, load shedding was scheduled to take place from 10:00 to 12:00 at the UFS. Currently, according to Centlec’s web site, stage 1 is active. This time slot is not marked in stage 1, therefore load shedding is not applied. Centlec gives also additional information; “No load shedding in progress.”

Keep in mind that if an area is at risk it does not automatically imply that the power will be switched off. It all depends on the request from Eskom at that particular moment whether the actual shedding is required.
 

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