Abstract:

During last years, technical careers are experimenting a noticeable reduction in the number of the students. Notwithstanding, industrial sector is today the basis of the economy. Without the technological development of the industries, society would not have access to a wide range of products or services. Therefore, it is extremely important to foster these vocations. In this sense, the Department of Chemical Engineering of the Universitat de Girona aims to promote these studies by performing different demonstrative experiences for high school students. One of the workshops was the reduction from hexavalent chromium (Cr(VI)) to trivalent chromium (Cr(III)) to reduce its toxicity.

Chromium is a natural element found in water, plants, animals and soil. In nature, chromium is basically found in two oxidation states: Hexavalent chromium (Cr(VI)) or trivalent chromium (Cr(III)). Hexavalent chromium is widely used in the production of textile dyes, inks, plastics, surface coatings and anti-corrosion products, among others. However, an increasing environmental awareness of the society has resulted in the apparition of new and more sustainable chemical processes. By one hand, it has been medically certified that the hexavalent chromium compounds are genotoxic carcinogens. Particularly, the chronic inhalation of this compound increase the risk of contracting respiratory cancers. In that sense, Cr(VI) can be reduced to Cr(III) via reduction-oxidation reaction. The trivalent chromium is relatively harmless due to its insolubility.

The experience was developed for several students ranging from 14 to 17 years old. Finally, students performed a Kahoot with the aim to know the degree of student’s interest in the experience and the satisfaction in the chemical engineering degree. The obtained results showed the experience as helpful to understand what chemical engineering is.

Keywords:

Sustainability, chemical engineering.