Properties and applications of palygorskite-sepiolite clays

TLDR

The palygorskite‑sepiolite group of clay minerals is widely used industrially because their sorptive, rheological, and catalytic properties arise from their fabric, surface area, porosity, crystal morphology, structure, and composition, and evaluating their mineralogical and chemical composition along with basic physical and physico‑chemical parameters is essential for assessing potential applications. This paper revises the principal characteristics of commercial palygorskite‑sepiolite clays and proposes potential uses, particularly new products and environmental protection applications. The authors modify and improve these clays’ properties through thermal, mechanical, acid treatments, surface‑active agents, and organo‑mineral derivatives, and they discuss possible health effects of the elongate minerals.

Abstract

Abstract The palygorskite-sepiolite group of clay minerals has a wide range of industrial applications derived mainly from its sorptive, rheological and catalytic properties which are based on the fabric, surface area, porosity, crystal morphology, structure and composition of these minerals. For assessing potential industrial uses, the mineralogical and chemical composition of the clay and its basic physical and physico-chemical parameters must be determined. Then some particular properties of commercial interest can be modified and improved by appropriate thermal, mechanical and acid treatments, surface active agents, organo-mineral derivatives formation, etc. In this paper, a revision of the principal characteristics of commercial palygorskite-sepiolite clays is presented, and potential uses are suggested according to these data. New products and applications are being investigated and those concerning environmental protection in particular, are noted. Finally, possible health effects of these elongate clay minerals are discussed.