1. Natural Organic Matter in SA Waters: Characterisation and treatability- our capabilities “Sustainable water resource”

2. Nanotechnology and Water Sustainability Unit (NanoWS @ UNISA)  Multi-disciplinary research unit focussing on: nanotechnology (nanomaterials) for water treatment advanced water treatment technologies (membranes) optimisation of conventional water treatment technologies water reuse, wastewater reclamation, “new water” from AMD  The researchers in the group and collaborators include materials scientists, analytical chemists, applied chemists, nanoscience research specialists, materials engineers, biosciences engineers, water and environmental engineers

3. RESEARCH FOCUS AREAS Nanostructured Membranes, Composites and nanocomposites Toxicology, nanotoxicology and development of analytical methods and protocols Urban Water Cycle (Water reclamation, reuse, NOM, and drinking water treatment) Bioremediation and analysis (Constructed wetlands and biotoxins analysis) Community Engagement (Training)

4. STRUCTURE OF NOM

5. CHEMICAL DESCRIPTION OF NOM FRACTIONS (i)Hydrophobic acid: carboxylic acids of five to nine carbons, one and two-ring aromatic carboxylic acids, aromatic acids, one and two-ring phenols and tannins. (ii)Hydrophobic base: are proteins with one and two-ring aromatic amines except for pyridine and high molecular weight alkyl. (iii)Hydrophobic neutral: a mixture of hydrocarbon and carboxyl compounds. (iv)Hydrophilic acid: aliphatic acids of less than five carbons, hydroxyl acids, sugars, low molecular weight alkyl monocarboxylic acids and dicarboxylic acids. (v)Hydrophilic base: Amphoteric proteinaceous materials containing amino acids, amino sugars, peptides and proteins. (vi)Hydrophilic neutral: aliphatic amides, alcohols, aldehydes, esters, polysaccharides and ketones with less than five carbons.

6. NOM IN THE ENVIRONMENT Terpenoid Humic Acid Amino Sugars 3-Acetonedicarboxylic acid Tannic acid D-xylose Hydrophobic HPO Transphilic TPI Hydrophilic HPI

7. NOM IN THE WATER TREATMENT TRAIN Ferric Disinfection Coagulation FlocculationEffluent HPI HPO DBPs  Disinfection byproducts (Health and social).  Colour, undesirable taste and odour (water quality).  Corrosion of distribution network (Costs).  High disinfectant demand (Costs).  Eutrophication (Environmental)

8. What do we need to know about NOM to understand its treatability? DOC concentration at source Charge load How much coagulant do we need? Zeta potential (charge removal) Membrane fouling How do we optimise the process? Fractionation No idea! (yet) How much DOC will remain? What DBPs will form?

9. NOM CHARACTERIZATION

10.  Isolation and/or concentration of NOM from source waters.  Fractionation into groups (fractions) of compounds with similar physical or chemical characteristics.  To identify which fractions dominates the NOM.  Develop and employ methods to remove problematic fractions.  Use of NOM fractions to investigate the effects of NOM on various water treatment processes and health effects. CHARACTERIZATION OF NOM

11. NOM FRACTIONATION Hydrophobic NOM High aromatic content High UV254 Humic Hydrophilic NOM Less aromatic (aliphatic) Lower UV254 Non- Humic Dissolved organic carbon

12. C18CN/NH2 HPO TPI HPI HPI Fraction NaOH HPO Fraction TPI Fraction NOM sample FRACTIONATION OF NOM (PRAM)

13. DISINFECTION BY-PRODUCT FORMATION (POTENTIAL)

14. SIMULTANEOUS FEEM ABSORBANCE

15. TYPICAL RAW SURFACE WATER FEEM