UNG Students Develop Eco-Friendly Adsorbent to Tackle Liquid Waste

Students from Gorontalo State University (UNG) have developed an eco-friendly adsorbent to tackle liquid waste, particularly from the tofu-making industry. The young research team, led by Nola Charmelita Bagenda, noted that the tofu industry is the economic backbone for communities in many parts of Indonesia, including Gorontalo. Unfortunately, behind this savoury protein product lies a complex environmental challenge: liquid waste with high organic content. Without adequate treatment, this waste triggers pungent odours and damages river ecosystems due to high levels of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD). Nola stated they successfully synthesised a composite material from fly ash and zeolite as an effective and economical waste adsorbent medium. The research is titled ‘Synthesis and Application of Composite (Fly Ash-Zeolite) as an Adsorbent Medium for BOD and COD Reduction in Tofu Industrial Liquid Waste’. ‘We initiated this through the Exacta Research Student Creativity Programme (PKM-RE) scheme,’ said Nola. The research promotes a circular economy approach by utilising fly ash, a waste product from industrial coal combustion, combined with zeolite to produce a composite material with high absorbency. This approach is compelling because it uses waste to solve other waste problems. Fly ash, which has been underutilised, is processed into a functional material capable of adsorbing organic pollutant compounds in tofu liquid waste. ‘Through the synthesis process of the fly ash–zeolite composite, the resulting adsorbent proved capable of significantly reducing BOD and COD values, thus potentially curbing the impact of water pollution,’ she said. Besides being effective, this technology is considered more economical and easy to apply by small and medium-sized enterprises. The use of raw materials from industrial waste makes production costs relatively low, while adding value to material previously considered worthless. Thus, this innovation is not only oriented towards environmental protection but also supports economic sustainability. The research results are expected to become an alternative eco-friendly liquid waste treatment technology, helping the tofu industry meet waste quality standards according to regulations and preserving aquatic ecosystem sustainability. ‘The development of adsorption technology based on local materials has the potential to be replicated in various regions with similar industrial characteristics,’ said Nola. This research also supports government efforts in pollution control and water quality management, in line with the Sustainable Development Goals (SDGs), particularly regarding clean water and sanitation and sustainable industry. This innovation is proof of the role of students in presenting applicable scientific solutions to real problems in society.