Malays. J. Anal. Sci. Volume 29 Number 4 (2025): 1392

Review Article

The potential of natural adsorbents for ammoniacal nitrogen removal in Malaysia’s industrial wastewater: A mini review

Nurul Izzah Adnan¹, Mohammad Arif Budiman Pauzan^1*, Syazwan Hanani Meriam Suhaimy¹, Noorul Hudai Abdullah², and Norfadhilatuladha Abdullah³

¹Department of Physics and Chemistry, Faculty of Applied Sciences and Technology (FAST), Universiti Tun Hussein Onn Malaysia (UTHM), Pagoh Higher Education Hub, 84600 Pagoh, Muar, Johor, MALAYSIA

²Centre of Diploma Studies, Faculty of Engineering Technology (FTK), Universiti Tun Hussein Onn Malaysia (UTHM), Pagoh Higher Education Hub, 84600 Pagoh, Muar, Johor, MALAYSIA

³Kinematic Resources Sdn Bhd, 25-3, Jalan PJS 5/30, 46150 Petaling Jaya, Selangor, MALAYSIA

^*Corresponding author: arifp@uthm.edu.my

Received: 17 October 2024; Revised: 28 March 2025; Accepted: 13 April 2025; Published: 31 August 2025

Abstract

Ammonia pollution in wastewater poses a significant environmental challenge thus adversely affecting both water quality and public health especially in developing countries like Malaysia. This review seeks to highlight the potential of various natural adsorbents for effective ammonia removal, focusing specifically on their suitability within the Malaysian context. The findings reveal that locally available materials such as coconut husk, palm oil biomass, biochar and algae possess substantial ammonia adsorption capacities which employ mechanisms like ion exchange and other physicochemical interactions. Notably, modified coconut husk and activated carbon produced from agricultural waste have shown impressive ammonia removal efficiencies reaching up to 88.6%. The implications of this research are considerable. Incorporating these natural adsorbents into wastewater treatment strategies not only improves ammonia removal but also supports sustainability by utilizing agricultural and industrial by-products, thus addressing both pollution and waste management issues. Additionally, this review underscores the importance of aligning these practices with environmental regulations of Malaysia. Future research should concentrate on optimizing adsorption conditions, investigating the regeneration capabilities of these natural materials, and developing hybrid treatment systems to enhance nitrogen removal efficiency in various wastewater contexts. By leveraging local resources and promoting environmentally friendly solutions, Malaysia can advance towards a more sustainable approach to managing industrial wastewater and mitigating the effects of ammonia pollution on sensitive ecosystems.

Keywords: ammonia removal, wastewater treatment, natural adsorbents, coconut husk, palm oil biomass

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