Enhancement of practical use of natural coagulant, Moringa oleifera extract, by simple purification and optimization of salt concentration

This study explored a facile purification to minimize salt and organic materials in natural coagulants from the extract of Moringa oleifera seeds. Salt (NaCl) solution 0.3 M had the best coagulation efficiency and high protein concentration crude extract for turbid water (nearly 90% removal at 100-150 NTU Kaolin). A subsequent dilute-precipitation process formed an insoluble gel that slightly decreased the crude Moringa extract coagulation efficiency but significantly reduced the residuals and improved the treated water quality. Results from this study have significant implications for practical application in safe water supply in climate change affected regions and where Moringa seeds available. • Facile purification of coagulant by precipitation simply with dilution of salt extract • oThe purified gel suspension obtains slightly lower turbid removal to the crude extract • oThe purification could reduce residual salts and organics in treated water • oThe improvements of a renewable natural coagulant promote sustainable water supply