Bentonite specific weight: weight of 1 m³ and density

Humans have long learned to use the useful minerals of our planet for their needs. Oil, coal and metal ores have long been widely used in industry, but some natural substances entered our lives comparatively recently. Bentonite, or bentonite clay, belongs to such useful minerals.

Physical Properties of Bentonite

Bentonite clays are fine-dispersed rocks of a waxy nature. Clay color can vary from pale yellow and grayish to green, bluish and even brown depending on the amount and variety of mineral impurities.

Bentonite formed during periods of increased volcanic activity on our planet. Ash, tuffs and lava underwent chemical changes when entering seawater or during surface weathering. As a result, clay rocks with unique water-absorbing and sorption characteristics were formed.

• The main property of hydrous aluminosilicate is swelling during hydration and retaining moisture inside the formed clot. When wetted, bentonite can increase in volume by 16-20 times. If clay is placed in a confined space and water is added, it turns into a gel-like substance and will no longer accept or pass additional moisture. Thus, bentonite can be considered ideal waterproofing. This feature began to be used in construction for:

• foundation laying;

• swimming pool construction;

• production of waterproofing bentonite mats.

• In its natural state, with moisture content not exceeding 15%, the specific weight of bentonite is 2.5-2.76 g/cm3, and volumetric weight is 0.93-1.96 g/cm3.

For convenient conversion, specific and volumetric weight data for bentonite are shown in the table.

• Bentonite sinters at 900-950 ºC, with a maximum temperature of 1430 ºC.

Two types of bentonite are distinguished:

• calcium bentonite, characterized by a low degree of swelling, up to 7 mg/g;

• sodium bentonite, with a high degree of water absorption, more than 12 mg/g.

Such bentonites are called activated, but in natural form the indicators can differ significantly.

Areas of Use

Bentonite is used not only in construction. The biological activity and non-toxicity of the mineral make it possible to use it as a component of various formulations in medicine, the food industry, fabric production, cosmetology and perfumery.

Bentonite has a special place in winemaking. It is used to clarify wines and fruit juices, and its sorption properties are used to remove protein and microorganisms from must and to adsorb oxidative enzymes.

Bentonite of different forms is placed in aquariums and terrariums as decorative elements.

When bentonite is added to feed and soil, crop yields, productivity and live weight gain of animals increase, digestion and immunity improve, because bentonite clays are a source of useful minerals and trace elements as well as biologically active substances.

Bentonites are used as adsorbing coloring pigments in some construction paints, as a binder or directly adhesive agent, and in the production of wallpaper and asbestos cardboard.

In mining and processing industries, bentonite clays are used as a component of drilling fluids, as additives in concretes to increase strength and water resistance, for producing expanded clay and agloporite, and as an element in the production of ferrous metallurgy alloys.