How is oxalic acid extracted from guava fruit?

Answer 1

A MASH of guava fruit is oxidized in the presence of vanadium pentoxide. This produces the diesters of oxalic acid which are then hydrolyzed to oxalic acid.

Answer 2

Oxalic acid can be extracted from guava fruit by first crushing the fruit to release the juice, then filtering the juice to remove solid particles. The juice can then be heated and treated with a calcium source such as calcium hydroxide to form calcium oxalate precipitate, which can be separated to obtain oxalic acid. The oxalic acid can then be further purified through crystallization or other methods.