Modification of bentonite clay & its applications: a review

Abstract

Bentonite clay is one of the oldest clays that humankind has been using from ancient times as traditional habits and remedies. In recent years researchers have found many applications of bentonite clay due to its various physio-chemical properties. In the present work, various physical and chemical properties of bentonite such as surface area, adsorption, swelling properties, cation exchange properties, etc. have been studied. This study also includes various procedures of modification of bentonite clay into Chitosan/Ag-bentonite composite, Fe-Modified bentonite, Hydroxyl-Fe-pillared-bentonite, Organo Bentonite, Organophilic clay, Arenesulfonic Acid-Functionalized Bentonite, Bentonite clay modified with Nb2O5. The study reveals that bentonite clay has large surface area due to similar structure with montmorillonite and it is found that the functionality of bentonite can be increased by increasing total surface area of the clay. Due to high cation exchangeability of bentonite, various cations can be incorporated into it. After purification and modification, the absorbent aluminum phyllosilicate bentonite clay can be used as an efficient catalyst in various types of catalytic reactions. Moreover, bentonite clay can be applied in various field like drilling, civil engineering, agriculture and water treatment.

Co–Fe catalyst supported on acidified bentonite for selective hydrogenation of cinnamaldehyde

“…The typical structure of bentonite consists of two Si–O tetrahedra sandwiched by an Al–O octahedron, where oxygen bonds link the platforms of Al and Si. 21 When the metal ions for which cation exchange occurs are reduced to particles, the metal layers of the bentonite will disappear, ultimately decreasing the bentonite layer spacing. Like in the same synthesis methods, reduced Co–Fe/BT and Co–Fe/ACBT have the same layer spacing and similar XRD patterns.…”

A Biodegradable High-Performance Microsupercapacitor for Environmentally Friendly and Biocompatible Energy Storage

“…36,37 Bentonite, as the main component of clay, is considered an environmentally friendly substrate for the breeding of some microorganisms. 38 Besides, bentonite has been chosen as a medicine to treat diseases such as diarrhea, proving its good biocompatibility. LiCl with a high solubility typically achieves low freezing points and significantly extends the operating voltage window of the device.…”

“…Importantly, both AC and graphene show environmental friendliness. Carboxymethyl cellulose (CMC) as the binder is renewable and degradable as a derivative of cellulose, which is essential for our devices. , Bentonite, as the main component of clay, is considered an environmentally friendly substrate for the breeding of some microorganisms . Besides, bentonite has been chosen as a medicine to treat diseases such as diarrhea, proving its good biocompatibility.…”

Preparation of Amphiphilic Chitosan-Loaded Bentonite Adsorbent and Its Performance in Removing Organic Matter from Coking Wastewater

“…BT has a large specific surface area, which is beneficial in improving the adsorption capacity and efficiency when it is being used as a wastewater adsorbent [ 13 ]. However, although BT is rich in mesopores and has a large specific surface area, its adsorption performance is easily affected by environmental factors [ 14 ]. For coking wastewater, the high fluctuation in wastewater quality has limited its application in the field of water treatment.…”