Unlocking the Heterogenization of Catalytic Chlorination Using Pyrrhotite Ash as an Efficient Magnetically Recoverable Heterogeneous Catalyst

Waste management is a central advantage of heterogeneous catalysis, as it enables catalyst recovery, reuse, and a significant reduction in hazardous byproducts, thereby improving environmental sustainability ^[1]. In this context, the catalytic chlorination reaction provides an efficient route to synthesize natural allylic chloride derivatives ^[2], which are important intermediates that serve as building blocks for more complex atomic arrangements ^[3], supporting cleaner and more sustainable chemical processes. Herein, the present work focuses on advanced characterization of Pyrrhotite ash (PA), an iron-rich industrial mining waste, using various techniques such as XRD, XRF, FTIR, Raman, ⁵⁷Fe Mössbauer spectroscopy and SEM-EDX. Thereafter, we have investigated for the first time its application as an efficient magnetically recoverable heterogeneous catalyst in selective chlorination of terpenic olefins using NaDCC as an eco-friendly and highly stable free available chlorine (FAC) agent ^[2,4]. The obtained results show PA as a promising alternative for the heterogenization of this reaction, enabling the production of valuable allylic chlorides from carvone and other terpenic olefins. This waste-to-resource approach emphasizes the potential of reusing industrial waste to support a circular economy and promote sustainable chemistry ^[4].

References:

[1] C. Vogt and B. M. Weckhuysen, Nature Reviews Chemistry, 6, 89–111, 2022.

[2] S. A. Labyad et al., RSC Adv., 13, 30548–30561, 2023.

[3] A. A. Mekkaoui et al., Journal of Chemistry, 2020, 1–8, 2020.

[4] S. A. Labyad et al., J. Environ. Chem. Eng., 14, 3, 122935, 2026.