The Sustainable Cotton Cluster is an initiative of Cotton SA, Government and like-minded cotton industry value chain stakeholders. It creates an enabling environment for cotton producers and manufacturers to supply local and international customers with fully traceable and sustainable cotton products. One of its aims is to promote research and development in the cotton industry.
Over the past year or so, researchers at the Northwest University (NWU) in Potchefstroom have been doing pioneering research funded by the Sustainable Cotton Cluster. Their work is part of the Cluster’s research and development mandate to develop cotton by-products that will increase the industry’s overall sustainability. Currently, no beneficiation of cottonseed oil and/or bio paraffin manufacturing is being done in South Africa.
Prof Sanette Marx and her team were contracted to determine whether cottonseed oil could be a viable source of paraffin/kerosene. “As far as we could find out, nobody else in the world has done similar research with raw pressed oil before,” says Prof Marx. “We were really excited to do the project.”
The Sustainable Cotton Cluster approached NWU as it is the only university in South Africa doing renewable diesel research. “We were already working with other oils, hence it was relatively simple to insert cottonseed oil into our experiments,” says Prof Marx.
The results were clear: raw, unrefined cottonseed oil is indeed a technically feasible source of kerosene/paraffin, as well as diesel and naphtha1.
Commercial viability was not included in the research scope and Prof Marx explains that production volumes are the biggest hurdle at present. South Africa does not produce enough cotton to justify the investment of building a cottonseed oil refinery. But there are other options.
“Our advice to the Sustainable Cotton Cluster was to partner with existing refineries that use crude oil to manufacture diesel and kerosene. The cottonseed oil can be blended with the crude oil during the refinery process. This will increase the kerosene yield and deliver a more environmentally friendly product that releases fewer particles into the atmosphere when it is burnt.”
This exact method was the topic of a student’s master’s thesis. He conducted his research at the Natref refinery with encouraging results, and has since been awarded his degree.
Prof Marx stresses that the Cluster project had merely scratched the surface. “The process involves a vast number of variables that should all be investigated to determine how it can be refined and improved.” A big and immediate challenge in this regard is to improve the process catalysts.
Exploratory as the project was, it benefitted both the university and the Sustainable Cotton Cluster, and opened up new possibilities for the cotton value chain in South Africa.