Preparation of a Gangue-Based X-type Zeolite Molecular Sieve as a Multiphase Fenton Catalyst and Its Catalytic Performance

Abstract

In this study, a series of X-type zeolite molecular sieve catalysts, modified with copper (Cu-X), were prepared by an alkali fusion–hydrothermal synthesis using coal gangue from Inner Mongolia. These catalysts were used in the degradation of the methylene blue dye by a Fenton-like reaction. Characterization results showed that Cu is considered to be present in the surface structure of the zeolite in the form of doped Cu ions and metal oxide. It is believed that Cu2+ is the main active site involved in the Fenton reaction. The X-ray photoelectron spectroscopy (XPS) spectra indicated that Cu2+ and Cu+ coexist in the catalysts and participate together in the Fenton reaction. The degradation of methylene blue by the Cu-X catalysts was investigated to determine the optimal catalytic conditions in terms of six aspects: catalyst dosage, initial solution concentration, initial pH of the solution, H2O2 dosage, copper loading, and reaction temperature. The experimental results showed that CX-1.0 had excellent activity and stability for the degradation and decolorization of the methylene blue dye, which could completely degrade the dye within 90 min, and the total organic carbon removal rate reached as high as 97.8%. Electron spin resonance (ESR) and radical capture experiments showed that •OH played a dominant role in the Fenton-like reaction. Combined with XPS, ESR, and catalytic tests, the redox cycle of Cu+/Cu2+ was found to be accelerating the generation of reactive radicals in the Fenton system.

Self‐assembled Cupric Oxide Nanoclusters for Highly efficient chemodynamic therapy

“…Time dependent absorbance decrease at 664 nm was also monitored at pH 5.0, 6.5, 7.4, which showed obvious slower MB degradation at pH 5.0, further confirming the efficient ⋅OH production in neutral and weak acidic environments (Figure S3). There are more redundant H + to react with ⋅OH in lower pH [25a26] . This means the generated reactive ⋅OH radicals would be consumed, ultimately hinders ⋅OH production efficiency in lower pH.…”

Optimization of biodiesel synthesis from Jatropha curcas oil using kaolin derived zeolite Na–X as a catalyst

“…A similar observation was reported by Zhang and Wang for X-type zeolite following Cu loading at amounts higher than 1.0 g L −1 . 44 However, it is worth noting that the zeolite's crystallinity was retained after introduction of Na. However, there was observed reduction in the XRD peaks in the low 2 θ region after the third transesterification reaction cycle of biodiesel synthesis.…”

Extraction of Aluminum and Iron Ions from Coal Gangue by Acid Leaching and Kinetic Analyses

“…As seen from Figure 2, the coal gangue is a multiphase mixture [29], and the main phases in the coal gangue are kaolinite, quartz, brookite, montmorillonite, pyrite, and siderite [30], in which kaolinite and quartz are the main components. As shown in Table 1, the iron content is high, but the peaks of the iron-containing materials are lower, which indicates that the crystallinity of the iron-containing materials is low.…”