Zeolite/ZnO composites based on a Cuban natural clinoptilolite and preliminary evaluation in methylene blue adsorption

Abstract

Two composites based on a Zn 2+ exchanged natural clinoptilolite and ZnO nanoparticles were obtained by mechanosynthesis and 'in situ' methods. Characterization of resulting materials was carried out using XRD, Raman spectroscopy, TGA, FE-SEM and N 2 adsorption. XRD results showed that no significant changes in the crystalline structure of the zeolite took place due to the performed treatments. Thermogravimetric behaviour indicated a high thermal stability for all samples. Raman spectra exhibited the characteristic bands for clinoptilolite zeolite and ZnO reported in the literature and the RRUFF database. Morphology changes were observed between natural and exchanged clinoptilolite and the 'in situ' obtained composite. Textural analysis showed a decrease in surface area of 'in situ' composite compared with the exchanged zeolites, related to the partial nanoparticle deposition in the pore entrances. The adsorption studies of methylene blue in the zeolitic samples and composites showed that all evaluated materials were able to absorb the dye from aqueous solutions.

High photodegradation performance of ZnO nanoparticles supported on porous Zeolite Na-A: Effects of ZnO loading

“…Jagannatha et al, [9] worked on ZnO/Zeolite nanocomposite for photocatalytic elimination of benzophenone and caffeine which revealed increased photodegradation of > 80% compared to that of zeolites 10 % or pure ZnO. Similar results pertaining zeo/ZnO were also reported by Marrero et al, [10]. This implies that immobilization of ZnO NPs on a zeolite support can effectively increase the surface area leading to increase in the exposed active sites for photodegradation.…”

“…The results show an increase of the surface area, a behaviour that is common when a replacement of a monovalent cation by a divalent one is carried out. When the Zn 2+ exchange process occurs, one Zn 2+ cation occupies the place of two Na + cations which leads to a surface area increment [10]. Increase in surface area of the catalyst leads to stronger adsorption properties thus enhanced photodegradation properties.…”

Study of secondary porosity by SAXS and N2 adsorption in composite materials obtained from a Cuban natural clinoptilolite

“…The characterization by X‐ray powder diffraction, thermogravimetric analysis, Raman spectroscopy, and scanning electron microscopy of the prepared composites (reported previously by Costa Marrero et al 32 ) allowed to confirm the ZnO NPs inclusion in the clinoptilolite by both methods.…”

Bimetallic PCN-333 with Modulated Crystallization and a Porosity Structure for a Highly Efficient Removal of Congo Red

“…11 Among these methods, adsorption stands out due to its straightforward operation, high efficiency, and absence of secondary pollution. 12 Traditional dye adsorbents include activated carbon, 13 cellulose, 14 zeolite, 15 chitosan, 16 graphene oxide, 17 and so on. However, their adsorption capacity for numerous dyes is relatively low.…”