The objective of the following article is to find a decontaminant of mercury present in water through the sifting of watermelon rind. The proposed process to prepare the watermelon rind is to dehydrate it and sift it at 150 microns. It is meant to know how it will affect pH, particle size and contact size of different contaminated solutions of mercury. It is known that 70% of freshwater resources in Mexico are contaminated by substances, known as heavy metals, including mercury, which can be found in the form of metal, mercury salts or organic form. Watermelon has 93% water in its shell, it has properties that help it stand out as an ideal cleanser since it helps eliminate certain toxins in heavy metals. Thanks to the amounts of lycopene and its potential as an antioxidant, watermelon peel can eliminate the chemicals that accumulate in the water found in the human body, which makes it a very good option as a decontaminant for this project. One of the innovations that is considered the most important in this research and at the time of project implementation, is the disposal of waste in a favorable way, which is, the elimination of a large part of the watermelon waste, without causing another type of contamination or bad odors due to the rotting of the fruit, and at the same time favoring the decontamination of other means, in this case the polluted water.