Adsorption environmental microbiology.pptx

environmental microbiology

1. Methods for Removal of Dissolved Solids from Water Dr. Devendra Mohan Professor and Former Head Department of Civil Engineering Indian Institute of Technology (Banaras Hindu University) Varanasi – 221005

2. Distillation Process of separating components of a liquid mixture through selective evaporation and condensation

3. Solar Distillation Process to use solar energy to purify water through evaporation and condensation

4. Chemical Precipitation Process of converting a soluble substance into an insoluble form by adding chemicals to it Applications of chemical precipitation include: Water Treatment Metal Extraction Chemical Analysis

5. Adsorption Adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to surface Surface Phenomena Adsorbate- ions, atoms, or particles that adhere to surface of adsorbent Adsorbent- material that has the ability to attract and hold molecules of a gas, liquid, or dissolved substance on its surface

6. Adsorption Vs Absorption

7. Ion Exchange Exchange of ions of the same charge between an insoluble solid and a solution in contact with it Used in water-softening and other purification and separation processes

8. Electrodialysis Water treatment process that uses an electric field to move ions through semipermeable membranes from one solution to another Applications: Desalination Drinking water production Food processing

9. Microfiltration Removes large particles like suspended solids, bacteria, and some viruses Does not remove dissolved substances like salts or small molecules Applications : Clarification of liquids like beverages. Wastewater treatment (removing bacteria and suspended solids). Pre-treatment for other processes like ultrafiltration or reverse osmosis.

10. Ultrafiltration Removes larger molecules such as proteins, colloids, and viruses, as well as bacteria Still allows small molecules like salts, sugars, and smaller organic compounds to pass through Applications : Protein separation in biotechnology and pharmaceuticals. Water purification (removing pathogens). Pretreatment for nanofiltration or reverse osmosis.

11. Nanofiltration Removes multivalent ions, small organic molecules, and some dissolved salts Allows monovalent ions like sodium (Na⁺) and chloride (Cl⁻) to pass through but with partial rejection Applications : Softening water by removing divalent ions like calcium and magnesium Removing color, pesticides, and organic compounds from water Separation processes in food and beverage industries

12. Reverse Osmosis Removes almost all dissolved salts, ions, and small molecules, including monovalent ions like Na⁺ and Cl⁻, as well as organic compounds Capable of producing near-pure water by removing dissolved solids, bacteria, viruses, and chemicals Applications : Desalination of seawater or brackish water Purification of drinking water Industrial water treatment and wastewater recycling Pharmaceutical production and food processing

13. CDI (Capacitive Deionization) Electrochemical water treatment process used to remove dissolved ions from water How CDI Works: Ion Migration Electrostatic Adsorption Water Purification Regeneration

14. Nalgonda Technique Removal of fluoride from water Chemicals used in the Nalgonda technique are alum (aluminum sulfate), lime (calcium oxide), and bleaching powder

15. Prashanti Technique  Water treatment method that uses activated alumina to remove fluoride from water Can be used for both community and domestic defluoridation

16. AMRIT AMRIT stands for Arsenic and Metal Removal by Indian Technology  Technology utilizes   nano -scale iron oxy-hydroxide,  which selectively removes arsenic when water passes through it AMRIT is applicable for both  domestic and community-level water purification

17. Arsiron Nilogon Iron-based coagulant specifically designed for the removal of arsenic from water Found effective for both As(III) and As(V) forms of arsenic Performance depend on factors such as pH, concentration of arsenic, and the presence of other ions

18. Arsiron Nilogon

19. Sono filter Water filtration system designed to remove arsenic from drinking water Filter uses a composite iron matrix, river sand, wood charcoal, and brick chips to remove up to 98% of arsenic and other contaminants

20. SORAS SORAS stands for Solar Oxidation and Removal of Arsenic Process uses solar energy to oxidize arsenic in contaminated water for removal of arsenic Benefits of SORAS : Low-cost Environmentally Friendly Easy to implement in rural areas

21. Sand coated with iron Used for removing arsenic from water In this method, a thin layer of iron is coated onto sand particles, which enhances the adsorption of arsenic when water passes through the filter

22. Sand coated with manganese Used for removing arsenic from water Manganese dioxide coating enhances the ability of the sand to adsorb arsenic, especially arsenic (III) and arsenic (V), through an oxidation-adsorption process.