Modification of Bentonite with Cationic and Nonionic Surfactants: Structural and Textural Features

Area of Science:

• Materials Science
• Environmental Science
• Surface Chemistry

Background:

• Surfactant-modified clay minerals exhibit excellent sorption capabilities for organic and inorganic compounds.
• Limited understanding exists on the combined effects of cationic and nonionic surfactants on bentonite properties.

Purpose of the Study:

• To elucidate the impact of cationic and nonionic surfactants on bentonite characteristics.
• To investigate the adsorption behavior of nonionic surfactants onto bentonite modified with cationic surfactants.

Main Methods:

• Bentonite modification using hexadecethyltrimethylammonium bromide (cationic) and Triton X-100 (nonionic).
• Characterization via X-ray diffraction (XRD), TG/DTA, FTIR, SEM, and BET surface area analysis.

Main Results:

• Cationic surfactant significantly enhanced nonionic surfactant adsorption onto bentonite.
• Increased nonionic surfactant concentration improved modification effectiveness.
• Modification decreased specific surface area but enhanced hydrophobicity and thermal stability.
• No interlayer expansion of smectite was observed with nonionic surfactant modification.

Conclusions:

• The amount of nonionic surfactant critically influences the properties of the resulting hybrid material.
• Combined surfactant modification alters bentonite's surface properties, enhancing its potential for contaminant sorption.