Renewable and sustainable water treatment using Moringa oleifera Lam. and biochar

The use of Moringa oleifera (MO) Lam. and biochar has been widely researched. This study, however, attempts to explore straightforward, cost-effective, and environmentally friendly methods for domestic application of MO and biochar for water treatment. To achieve this goal, the researcher first identified the contaminants generally present in water and their prescribed limits in drinking water in developed countries and some developing regions. Their potential health impacts and the conventional removal methods were critically analysed regarding their merits and demerits. The literature review justifies the need to explore sustainable and affordable methods for water treatment. MO and biochar have the potential to provide clean drinking water by removing contaminants through coagulation-flocculation and adsorption, respectively. Regarding using Moringa oleifera, the current study fills the gap in the literature by exploring the optimum dose, shelf-life, settling time, storage temperature and the extractant used for moringa seed protein to treat water with low hardness and low conductivity, especially in cold climate regions. Further, this research, for the first time, investigated the influence of particle size (PS) on the efficiency of MO seeds in removing turbidity and pathogens from drinking water. For this purpose, the seed powder was sieved into five different PS, and the optimum size range for water treatment was explored. The research further investigated the potential of biochar as a low-cost, globally available adsorbent to remove heavy metals such as cadmium, zinc, nickel, and lead from water. The study employed sewage sludge biochar (SSB) without surface modification, achieving a high adsorption capacity and removal percentage. The prospective of SSB in removing arsenic (metalloid) from drinking water was also studied. Surface-modified SSB (using a 2M KOH solution) exhibited promising results compared to its pristine counterpart. The water obtained closely met WHO criteria for drinking water. Finally, the researcher focused on developing a laboratory-scale hybrid system that sequentially uses MO and biochar to remove turbidity, pathogens, and heavy metals from water. Synthetically contaminated water with a turbidity of 200 NTU was prepared. The water contained 10 mg/l of each nickel (Ni) and lead (Pb) and 1x105 colony-forming units (CFU/ml) of Escherichia coli (E. coli) bacteria. It was first treated with MO and then passed through a column containing non-modified sewage sludge biochar. Encouraging results were obtained. The turbidity of the finally treated water was around 1 NTU. Ni and Pb were removed by 97.5% and 99.3% respectively. E. coli in treated water were not detected. The finally treated water met the WHO and UK criteria for potable water. This is the first study that makes sequential use of Moringa oleifera Lam. and biochar as natural resources to obtain clean drinking water.

Name dc:type.qualificationname

PhD

Grantor dc:publisher.institution

University of Wolverhampton

Year dc:date.issued

2025

Author dc:creator

• Shah, Ahsan Abbas

Advisors dc:contributor.advisor

• Arjunan, Arun
• Zakharova, Julia

• sustainable water treatment
• water contaminants
• heavy metals
• pathogens
• E. coli
• turbidity
• Moringa oleifera
• biochar
• adsorption
• coagulation

Licence

• https://wlv.openrepository.com/bitstreams/ead03657-730b-445f-b9e2-8749a6b2af4e/download