Photodegradation of Methyl Green by Nickel‐Dimethylglyoxime/ZSM‐5 Zeolite as a Heterogeneous Catalyst

Abstract

Ni-DMG/ZSM-5 zeolite was prepared by ion exchange and complexation procedures. FT-IR, XRD, SEM, TG, and DTG methods were used for characterization of the raw and modi�ed samples. e prepared composite was used as a catalyst in the photodegradation process of an aqueous solution methyl green (MG) dye under UV irradiation. e effect of key operating parameters such as catalyst dosage, temperature, the initial concentration of the dye, and pH of the samples was studied on the degradation extent of the dye. UV-Vis spectrophotometric measurements were performed for determination of the decolorization and mineralization extents. e optimal operation parameters were found as follows: pH = 9, temperature of 60 ∘ C, 0.6 g L −1 of the catalyst, and 40 ppm of the dye concentration. e Ni-DMG particles out of zeolite framework did not show signi�cant degradation efficiency. e degradation process obeys the �rst-order kinetic.

Chemometrics investigation of the light-free degradation of methyl green and malachite green by starch-coated CdSe quantum dots

“…The way of data matrix augmentation and bilinear decomposition by MCR-ALS is shown in Figure 4. is supported by earlier report on mechanistic study of photodegradation of methyl green on TiO 2 using HPLC-PDA-ESI-MS technique [54], whereproducts of methyl green degradation categorized into two groups illustrated in Fig.7. We assumed that compound ofFig.7a and b are corresponded to components of 5 and 4, respectively.…”

“…According to Fig.3a, at pH=7-9, decolorization efficiency reached more than 80% within 2.0 min corresponds to absorption decay at λ max = 632 nmfrom 1.2 to about 0.2. Enhancing photocatalytic activity at higher pH concurred with literatures [54,57]and canbe explained based on higher concentration of hydroxyl radical at higher pH (OH -+ h + → OH • ) that are scavenged more rapidly at a higher pH [58][59][60]. Similar trend were observed for photodegradation of Malachite green (MaG) in ambient condition (see Figure S1, Supporting Information).…”

Heterogeneous Fenton-like oxidation of crystal violet using an iron loaded ZSM-5 zeolite

“…3. All samples exhibited the typical diffractograms of the ZSM-5 zeolite (MFI framework) (2θ = 7-9˚and 23-25˚) given in literature [25,32,34,[46][47][48][49][50][51][52][53]. It emphasized that the high dispersion of Fe ions in the compensating positions inside the zeolites did not damage the crystallinity of the zeolite.…”

“…The broad band in the range of 3,000-3,500 cm −1 shows the Fe-OH vibration. The bands at 800, 1,100, and 1,225 cm −1 are assigned to different vibrations of the tetrahedral and framework structure of the ZSM-5 zeolite [52,53]. Similar peaks at 805, 1,090, and 1,290 cm −1 were observed in a study by Nezamzadeh-Ejhieh and Karimi-Shamsabadi [55] The band at about 1,100 cm −1 is due to the internal vibrations of the (Si, Al) O 4 tetrahedral of the ZSM-5, whereas the bands at 1,225 and 800 are due to Table 1 Some surface characteristics of the prepared catalyst and parent ZSM-5 zeolite …”

As-synthesized ZSM-5 zeolite as a suitable support for increasing the photoactivity of semiconductors in a typical photodegradation process

“…Synthesis of ZSM-5 (SiO 2 /Al 2 O 3 ¼80) was done according to typical procedure reported in our previous work and literature [23]. The synthesized zeolite was sieved by ASTM standards sieves and the particles with mesh below 400 were selected for the experiments.…”