Wet process for mixing materials

For quite sensitive compositions the wet process is used. In this case an amount of water is added to the materials when they are mixed, so that they lose their explosive nature. It is also possible to add an organic solvent, but in this case it is impossible to perfectly suppress the explosive nature. The wet process is not effective for materials such as picric acid salts, which are generally sensitive even in the presence of water. 

The wet process is operated as follows Dissolve a quantity of the binding material like gelatine etc. in the water. Weigh out an amount of well sieved oxidizer, add it to the solution in small amounts, stirring it well. Then add the red phosphorus powder, realgar or other fuels in small quantities to it to obtain a slurry. This slurry is pasted onto some supporting material in small quantities and these are packed with thin paper one by one. The pieces are dried naturally to recover their explosive nature, but the composition is now separated into small amounts and is safe to handle. 

During the wet process gelatine helps to prevent the chemicals from sedimentation, but some compositions are manufactured without such a binder. 

The wet process cannot be used of course for compositions where the components react with each other in presence of water. 

Wet compositions are generally used in conjunction with paper with the result that the components partially soak out to change their ratio. 

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