6 women using STEM to make the South African circular bioeconomy a reality
Today marks the International Day of Women and Girls in Science, and these six young women are using their expertise in science, technology, engineering, and mathematics (STEM) to make a mark in the circular bioeconomy.
Images supplied/Canva
The South African pulp and paper sector has been creating opportunities for young women who apply STEM to make the South African circular bioeconomy a reality.
Established by the Paper Manufacturers Association of South Africa (PAMSA), the Master’s in Engineering bursary and research programme has helped several young women pursue postgraduate studies in chemical engineering, wood science and related disciplines over the past 15 years.
“As a sector centred on the renewability of wood-derived products such as cellulose, paper, packaging and tissue, our students’ research projects enable our members to improve efficiencies and close the loop in the manufacturing process,” says Jane Molony, executive director of PAMSA.
The range of research projects is vast — from putting process by-products and waste streams such as lignin, sludge and even food waste to higher-value use, to optimising water and energy efficiency.
The women behind the projects
Sonja Boshoff. Image supplied.
Sonja Boshoff
“One of our earlier students is Sonja Boshoff, who graduated from the programme in 2015.
“She is a thriving process engineer in an all-female team at Mpact that is passionate about incorporating innovative technologies and practices to ensure both sustainability and profitability,” says Molony.
Boshoff was instrumental in kick-starting the early research that ultimately led to a bioethanol production project using sludge from the pulp and paper industry.
“Paper sludge is rich in organic material such as cellulose, making it a promising feedstock for bioethanol production,” Boshoff explains.
Bioethanol serves as a platform chemical in the production of industrial chemicals, bio-based plastics and even sustainable aviation fuel.
“The launch of a bioethanol demonstration plant in 2024 marked the culmination of more than a decade of research by Stellenbosch University’s Department of Chemical Engineering and its Bioresource Engineering research group, which Boshoff was part of,” notes Molony.
After completing her master’s project, Boshoff moved on to the Mpact Innovation Centre in Stellenbosch, where she did further research on alternative technologies for recovering energy from waste.
Leane Naude
Leane de Beer. Image credit: Sappi
Leane Naude, who completed her MSc in Chemical Engineering at North-West University in 2020, explored a more cost-effective purification method for lignosulphonate, a lignin-derived by-product of the pulping process.
Her work focused on converting what is typically a low-value material into higher-value applications, supporting the circular bioeconomy and reducing reliance on fossil-based inputs.
Further work on lignin is ongoing at the Sappi Technology Centre, and Naude is progressing in her career as a chemical engineer, working on environmental projects, lifecycle assessments, simulation modelling and water management plans.
Mahlogonolo Mafela
Mahlogonolo Mafela. Image credit: Mpact
A junior process engineer at Mpact, Mahlogonolo Mafela, investigated how to optimise energy use in the paper manufacturing process by researching different vacuum levels and times to achieve optimal pulp dryness during paper formation.
She explains that when the mixture is exposed to a vacuum, water can be removed, much like squeezing a sponge.
“We are basically using a vacuum to squeeze as much water as possible, so I wanted to reduce the energy consumption required by the vacuum pressure process but still optimise water removal,” says Mafela.
Kelly Campbell. Image supplied.
Kelly Campbell
Kelly Campbell, who holds a BEng in Chemical Engineering and is completing her MEng at Stellenbosch University, is focusing on food waste fermentation for ethanol production.
Her work responds to the growing challenge of organic waste destined for landfill.
"Instead of going to landfill, this waste could be converted into ethanol through fermentation,” Campbell explains.
“That diversion reduces landfill emissions and creates a high-value product with potential in the chemical and transport sectors.” Campbell is currently working at Mpact as an engineer-in-training.
Lerato Tau
Lerato Tau will be graduating with her master’s at the University of Pretoria this year.
Lerato Tau. Image supplied.
“For my project, I used thermogravimetric analysis (TGA) to measure how certain materials used in the papermaking process behave when heated,” says Tau.
Her project sought to study the makeup and thermal stability of feedstocks, process materials and final paper products.
“In simple terms, I’m heating up paper materials and watching how they lose weight as they get hotter,” Tau explains.
“Different components break down at different temperatures, which shows up as patterns on a graph. This tells me exactly what the material is made of – how much hemicellulose, cellulose, lignin and char it contains.”
The beauty of her method is its efficiency.
Traditional laboratory tests to analyse paper materials can take three days and require dangerous chemicals.
Tau’s heat-based approach delivers the same information in about six hours, making it safer, faster and more practical for the industry.
Gabriela Carzola. Image supplied.
Gabriela Carzola
Another example of the circular bioeconomy in action is the work of Gabriela Carzola, now a process engineer in training at an engineering firm.
Her master’s project through Stellenbosch University, which recently earned her a distinction, explored methods to convert papermaking reject material into a slow-release fertiliser for trees in commercial forestry plantations.
“The work of these incredible women demonstrates how our sector is driven by sustainability and innovation,” Molony concludes.
“By investing in women and girls in STEM fields, we are strengthening the forest-products value chain, supporting a circular bioeconomy with low-carbon alternatives and ensuring that we build a pipeline of young women for our sector’s future.”