Bentonite Properties

Bentonite is safe in many applications
Bentonite may be known by most people as cat litter. The dry granular bentonite absorbs a small amount of water and clumps the hydrated bentonite together. The ability of bentonite to absorb water is used in many of its other applications.

Sodium Bentonite was found near Fort Benton, Wyoming (hence the name bentonite) where its wet slurry was used by early pioneers as wheel grease (bentonite gel gets slippery when wet) and as a cream for sunscreen.

Bentonite (a thixotrope) is used today in oil drilling as a fluid to lubricate equipment, provide hydrostatic pressure, carry out suspended drill cuttings, keep the drill bit cool, and seal the well bore. The ability to form a waterproof seals between materials is one reason that bentonite is a basic component of drilling fluids. The bentonite is pumped into the well during the drilling operation to permanently seal the well shaft as it penetrates the various water bearing strata’s. This waterproof seal is vital if we are to prevent the water from contaminating the crude oil below it.

Bentonite is also used as a binding agent and flux in multiple applications such as in the manufacture of taconite pellets, and in foundry sand to make a moldable aggregate known as green sand. Variation in deposits of bentonite in the sand on beaches also accounts for the variety of plasticity of sand from place to place for building sand castles.

Bentonite is known to be non-toxic and non-carcinogenic. For this reason, bentonite has been used as a binding agent for pharmaceuticals and animal feed pellets, as a base for many skin creams and make up (much like the sunscreen of the early pioneers), used as both a laxative and a cure for dysentery (absorptive properties). Bentonite also has the interesting property of absorbing relatively large amounts of protein molecules from aqueous solutions. It is therefore uniquely useful in the process of wine making, where it is used to remove excessive amounts of protein from white wines. These food and pharmacological applications demonstrate bentonite’s safety.