Iodine and bromine are extracted from Laminaria and Rhodymenia.

Laminaria is a type of brown algae, commonly known as kelp. It is found in colder coastal waters and is harvested for various purposes, including the extraction of iodine. Rhodymenia, also known as dulse, is a red algae that is found in both cold and warm waters. It is also used for the extraction of iodine and bromine.

Iodine extraction from Laminaria and Rhodymenia:
1. Collection: Laminaria and Rhodymenia are collected from their natural habitats, mainly from the ocean. These algae are known to accumulate iodine and bromine in their tissues.

2. Drying: After collection, the algae are dried to remove excess moisture. This helps in the preservation of the algae and facilitates the extraction process.

3. Grinding: The dried algae are then ground into a fine powder. This increases the surface area, which allows for better extraction of iodine and bromine.

4. Extraction: The powdered algae are treated with a solvent, usually a mixture of water and alcohol. This solvent helps to extract iodine and bromine from the algae. The mixture is then filtered to separate the liquid extract from the solid residue.

5. Purification: The liquid extract obtained from the filtration process contains iodine, bromine, and other impurities. It undergoes further purification steps, such as distillation or chemical reactions, to separate iodine and bromine from the impurities.

6. Crystallization: Once purified, the iodine and bromine are crystallized from the solution. This involves cooling the solution, which causes the iodine and bromine to form crystals that can be collected.

7. Drying and packaging: Finally, the iodine and bromine crystals are dried to remove any remaining moisture. They are then packaged and prepared for distribution and use.

In conclusion, iodine and bromine are extracted from Laminaria and Rhodymenia, two types of algae. These algae are collected, dried, ground, and then subjected to extraction processes using solvents. The resulting extracts are purified, crystallized, and finally dried and packaged for use.

It is characteristics of these algal Groups.

Brown alage ( Phaeophycae) have iodine
Examples are- Laminaria, Fucus, Dictyota, Ectocarpus and Macrocystis.

Red alage ( Rhodophycae) have bromine.
Examples are- Porphyra, polysyphonia, Gelidium, Gracilaria, Chondrous, Harveyella and Bactrachosporum.
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