Improved modification of clinoptilolite with silver using ultrasonic radiation

Abstract

The modification of natural clinoptilolite with silver ions using ultrasound has been investigated in the current work. The modification process was performed using clinoptilolite of different fractions (0–3.0 mm) over the temperature range of 25–55 °C, ultrasonic power range of 8.0–12.5 W and AgNO 3 concentration range of 0.01–0.1 M. The zeolite modification was performed in the presence of sonication and mechanical stirring in separate runs for comparison. Fundamental analysis demonstrated that the use of ultrasound ensures desorption of air from clinoptilolite particles and accelerates the diffusion of Ag + ions and subsequent ion exchange. Increasing the particle size of clinoptilolite led to a natural decrease in its sorption capacity. A slight increase in the sorption capacity with an increase in the equivalent particle diameter from 0.081 to 0.35 mm was seen due to changes in the structure of clinoptilolite particles during mechanical grinding. The calculated temperature coefficient of the sorption process of Ag + ions as <1.47 means that the modification takes place with dominant control in the intradiffusion region. Increasing the power of ultrasonic irradiation did not provide a monotonous change in the sorption capacity of clinoptilolite. Increasing the concentration of argentum nitrate solution provided an increase in the content of silver ions in clinoptilolite. In general, the advantage of using ultrasonic vibrations to modify the natural clinoptilolite of different fractions with Ag + ions was demonstrated in terms of achieving higher sorption capacity, also elucidating the effect of different operating conditions.

Fabrication of electrospun nanofibrous clinoptilolite doped thermoplastic polyurethane scaffolds for skeletal muscle tissue engineering

“…However, in the 5 wt.% CLN/TPU nanofiber structure (Figure 3b), calcium (Ca), aluminum (Al), silicon (Si) atoms were found to be present in addition to carbon atoms. 58 This result is a proof of the presence of CLN in the structure.…”

“…It is seen that the pure TPU nanofiber structure is predominantly carbon (C) and nitrogen (N) elements (Figure 3a). However, in the 5 wt.% CLN/TPU nanofiber structure (Figure 3b), calcium (Ca), aluminum (Al), silicon (Si) atoms were found to be present in addition to carbon atoms 58 . This result is a proof of the presence of CLN in the structure.…”

Preparation of Bactericadal Fillers From Georgian Heulandite-Clinoptilolite and Their Application for Paper Production. I. Bactericadal Fillers

“…The preparation of metal-containing zeolites is usually carried out by treating the zeolite powder in an aqueous solution of the corresponding salt, recently it has been shown that the use of ultrasound ensures desorption of air from clinoptilolite particles and accelerates the diffusion of ions and subsequent ion exchange [41].…”

Topically administered purified clinoptilolite‐tuff for the treatment of cutaneous wounds: A prospective, randomised phase I clinical trial

“…The medical utility of clinoptilolite results from its physicochemical properties that makes it suitable for medical use 16–18 . Clinoptilolite is strongly hygrophilic, possesses a unique ability for reversible cation exchange and a high adsorption capacity for diverse biomolecules 15–24 . Because of the resulting potential detoxifying effects, clinoptilolite‐based products have been proposed in many medical applications 16,18,23,25,26 .…”

“… 16 , 17 , 18 Clinoptilolite is strongly hygrophilic, possesses a unique ability for reversible cation exchange and a high adsorption capacity for diverse biomolecules. 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 Because of the resulting potential detoxifying effects, clinoptilolite‐based products have been proposed in many medical applications. 16 , 18 , 23 , 25 , 26 PCT is currently marketed for oral use aimed at preventing the absorption of toxins, heavy metals and dietary cholesterol.…”