Published 2026-04-23
Dr. Eka Fitriani Ahmad defended her dissertation in ITB’s Doctoral Program in Environmental Engineering on 16 April 2026. Her research explored coconut husk as a raw material for advanced air filters, connecting air pollution control with the productive use of agricultural waste.
As a major coconut producer, Indonesia generates substantial quantities of husk. The research examined how cellulose in this material could be engineered into filtration media, offering an alternative to conventional synthetic materials.
From Coconut Husk to Cellulose
The first step isolated α-cellulose through delignification using soda–anthraquinone (SAQ) catalysis. The source reports more efficient lignin removal and increased cellulose content compared with conventional methods. The resulting pulp contained 61–81% α-cellulose and supplied two complementary material synthesis routes.
The first route produced carbonized cellulose aerogels (CCAs) through a sol–gel process. Their semi-graphitic conductive architecture enabled particle capture through tunnelling-percolation charge transport and electrostatic Coulomb attraction. Optimised CCAs reportedly achieved removal efficiencies approaching 98.6% for PM2.5 and 99.0% for PM10.
The second route converted purified cellulose into cellulose acetate with a degree of substitution of approximately 2.5, followed by electrospinning into nanofibre membranes. Fibre diameters ranged from 70 to 220 nanometres, with controlled mesoporosity and surface area. Reported capture efficiency exceeded 95% for particles smaller than 50 nm, while the most penetrating particle size lay around 90–120 nm.
A Circular-Economy Pathway
The research considered scalability by integrating chemical purification, microstructural engineering, and electrostatic functionality. The laboratory proof of concept offers a pathway towards industrial development, rather than evidence that commercial production is already established.
Converting abundant coconut husk waste into higher-value filtration materials could reduce reliance on fossil-based synthetic feedstocks and connect agricultural value chains with environmental technology.
The defence was chaired by Prof. Andojo Wurjanto and attended by Prof. Puji Lestari, Prof. Katharina Oginawati, Prof. Muhammad Miftahul Munir, Prof. Indah Rachmahtiah Siti Salami, Dr. Asep Sofyan, and Prof. Yoki Yulizar of POLTEKNAKER.
The research opens opportunities for collaboration among universities, agricultural industries, and environmental technology developers to pursue sustainable filtration solutions relevant to Indonesia and other tropical coconut-producing countries.