Wet Peroxide Research Articles

Expression of the 2Duf protein in wild-type Bacillus subtilis spores stabilizes inner membrane proteins and increases spore resistance to wet heat and hydrogen peroxide.

This work aimed to characterize spore inner membrane (IM) properties and the mechanism of spore killing by wet heat and H2O2 with spores overexpressing the 2Duf protein, which is naturally encoded from a transposon found only in some Bacillus strains with much higher spore resistance than wild-type spores. Killing of Bacillus subtilis spores by wet heat or hydrogen peroxide (H2O2) was slower when 2Duf was present, and Ca-dipicolinic acid release was slower than killing. Viabilities on rich plates of wet heat- or H2O2 -treated spores +/- 2Duf were lower when NaCl was added, but higher with glucose. Addition of glucose but not Casamino acids addition increased treated spores' viability on minimal medium plates. Spores with 2Duf required higher heat activation for germination, and their germination was more wet-heat resistant than that of wild-type spores, processes that involve IM proteins. IM permeability and lipid mobility were lower in spores with 2Duf, although IM phospholipid composition was similar in spores +/- 2Duf. These results and previous work suggests that wet heat and H2O2 kill spores by damaging an IM enzyme or enzymes involved in oxidative phosphorylation.

Preparing Cu2O/Al2O3 Coating via an Electrochemical Method for the Degradation of Methyl Orange in the Process of Catalytic Wet Hydrogen Peroxide Oxidation

To improve the catalytic efficiency and decrease the reaction temperature of wet air oxidation technology, a Cu2O/Al2O3 coating was prepared on the surface of aluminium alloys by anodizing technology, and subsequent heating treatment. Then, the Cu2O/Al2O3 coating and 3 wt.% H2O2 was used to degrade methyl orange. The influence of the coating’s microstructure, crystalline component on the degradation rate of the methyl orange was studied. The microstructure of the coating was observed by scanning electron microscope. Results proved that the coating was composed of micropores, and Cu2O was evenly dispersed on the surface and pores in the Al2O3 coating. X-ray diffraction pattern analysis demonstrated Cu2O and Al2O3 characteristic peaks were found after the coating was treated at 300 °C, showing that amorphous Cu2O and Al2O3 were transformed into crystalline oxide. A UV-vis spectrophotometer was used to measure the absorbance of methyl orange, and it was found that the maximum absorption wavelength of methyl orange is 460 nm. At that wavelength, the suitable degradation condition of methyl orange was studied, and results showed that when electrochemical deposition time was 30 min and catalyst dosage was 8 g, the degradation rate of methyl orange could reach 92% at 25 °C for 120 min. Furthermore, when the catalyst was reused 9 times, the degradation rate still reached 75%. Based on the above results, a kinetic equation between the degradation rate of methyl orange and catalyst dosage was derived. The microstructure and crystalline component of the catalyst after different reuse times were characterized, and results showed that the catalytic efficiency of the Cu2O/Al2O3 coating decreased with a decrease in the coating’s specific surface area and the ratio of Cu2O in the coating.

Wastewater Treatment by Enhanced H2O2 – Based Advanced Oxidation Process (AOP) Methods: A Review

The development of industries leads to large amount of organic wastewater that contains phenol and dyes. For the treatment of these pollutants, the applications of H2O2 based – AOP have advantages in less pollution, low costs and high efficiency. In order to promote the degradation effect of H2O2, researchers used several methods to strengthen the effect of H2O2 based – AOP. This article mainly reviews the development of catalysts of the strengthened Catalytic Wet Hydrogen Peroxide Oxidation (CWPO), Fenton-like and other assistant-H2O2 systems in the degradation of phenol and dyes recent years. Challenges and development directions concerning catalysts in the future are discussed.

Remarkable CWPO of crystal violet dye removal using the fishbone doped of copper synthesized by impregnation method

This work aimed to study the remarkable catalytic performance of fishbone (FB) doped copper (Cu) synthesized by the impregnation method for crystal violet (CV) dye’s catalytic wet hydrogen peroxide oxidation (CWPO). The catalysts (x%Cu-FB) prepared were characterized by several techniques such as the X-ray diffraction (XRD), the Fourier transformed infrared spectroscopy (FTIR), the zero point charge measurement (pH zpc ), and the scanning electron microscopy (SEM) coupled by the energy-dispersive X-ray spectroscopy (EDX). In addition, this catalysis (x%Cu-FB) was employed as heterogeneous catalysts for CWPO of crystal violet dye removal using different parameters effects in particular the percentage of metallic precursor Cu, the catalyst amount, the concentration of CV dye, the hydrogen peroxide H 2 O 2 concentration, the temperature, the pH solution. The discolorization rate efficiency was boosted from 98% for 1% Cu-FB after only 35 min of reaction with the optimum conditions namely pH=10, [CV] = 20 mg L -1 , [H 2 O 2 ] =0.048 mol L -1 , W Cu-FB = 2 g L -1 and T=50°C. Finally, it can be seen from this study that the oxidation process by a fishbone catalyst could be economical and effective in removing a large part of the textile pollutants (CV dye) existing in industrial wastewater. The scope of the study makes this method a clean alternative that fits into a perspective of sustainable development.

Corrigendum to Catalytic wet hydrogen peroxide oxidation of isoeugenol to vanillin using microwave-assisted synthesized metal loaded catalysts [Molecular Catalysis 506 (2021) 111537

Corrigendum to Catalytic wet hydrogen peroxide oxidation of isoeugenol to vanillin using microwave-assisted synthesized metal loaded catalysts [Molecular Catalysis 506 (2021) 111537

Preparation of Supported Perovskite Catalyst to Purify Membrane Concentrate of Coal Chemical Wastewater in UV-Catalytic Wet Hydrogen Peroxide Oxidation System.

The effective treatment of membrane concentrate is a major technical challenge faced by the new coal chemical industry. In this study, a supported perovskite catalyst LaCoO3/X was prepared by a sol–impregnation two-step method. The feasibility of the supported perovskite catalyst LaCoO3/X in the UV-catalytic wet hydrogen peroxide oxidation (UV-CWPO) system for the purification of concentrated liquid of coal chemical wastewater was investigated. The effects of catalyst support, calcination temperature, calcination time, and re-use time on catalytic performance were investigated by batch experiments. The catalysts were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and X-ray photoelectron spectroscopy (XPS). Experimental results showed that the supported perovskite catalyst LaCoO3/CeO2 prepared using CeO2 as support, calcination temperature of 800 °C, and calcination time of 8 h had the best catalytic effect. The catalytic performance of the catalyst remained excellent after seven cycles. The best prepared catalyst was used in UV-CWPO of coal chemical wastewater membrane concentrate. The effects of H2O2 dosage, reaction temperature, reaction pressure, and catalyst dosage on UV-CWPO were determined. Under the conditions of H2O2 dosage of 40 mM, reaction temperature of 120 °C, reaction pressure of 0.5 MPa, catalyst dosage of 1 g/L, pH of 3, and reaction time of 60 min, the removal efficiencies of COD, TOC, and UV254 were 89.7%, 84.6%, and 98.1%, respectively. Under the optimal operating conditions, the oxidized effluent changed from high toxicity to non-toxicity, the BOD5/COD increased from 0.02 to 0.412, and the biodegradability of the oxidized effluent was greatly improved. The catalyst has a simple synthesis procedure, excellent catalytic performance, and great potential in the practical application of coal chemical wastewater treatment.

Catalytic wet hydrogen peroxide oxidation of isoeugenol to vanillin using microwave-assisted synthesized metal loaded catalysts

• Supported metal nanoparticles (Cu, W, Mo) on a silica matrix using a one-pot microwave-assisted protocol. • Catalytic activity evaluated in the oxidation of isoeugenol into vanillin. • Moderate conversions, up to 50–60 % (for Cu-MINT). • Acceptable selectivities towards vanillin production (22–45 %). • High catalyst stability (imperceptible decrease of activity after the fourth use). Supported metal nanoparticles (Cu, W, Mo among others) have been stabilized on a silica matrix following an efficient and sustainable one-pot microwave-assisted protocol. The materials synthesized were characterized, mainly, by nitrogen adsorption desorption measurements, X-ray diffraction (XRD), scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDS). The materials exhibited large surface area and pore size in the mesopore range. The incorporation of metal particles in the silica matrix was also confirmed with particle size in a wide range between 2 and 52 nm. The catalytic activity of the resulting materials was evaluated in the catalytic wet oxidation of isoeugenol into vanillin using hydrogen peroxide as oxidant. The catalysts shown moderate conversions, up to 50–60 % for Cu-MINT with acceptable selectivity towards vanillin production (22–45 %), obtaining dimers as main side products. The stability of the catalysts was investigated as well, obtaining an imperceptible decrease after the fourth use.

Copper-impregnated on natural material as promising catalysts for the wet hydrogen peroxide catalytic oxidation of Methyl Green

Promising catalyst of cooper impregnated on natural material (CT) synthesized via wet impregnation method, in order to enhance the catalytic wet peroxide oxidation during the degradation of organic matter in a batch reactor under mild conditions. Three different percentages of copper metal (2.5, 5 and 7.5 %) incorporated into CT material which are referred as follows 2.5% Cu-CT, 5% Cu-CT and 7.5% Cu-CT were investigated in the oxidation catalytic of methyl green (MG) dye. The chemical composition, the morphology and the structure of raw CT and all prepared samples, were investigated by X-ray fluorescence, Fourier transform infrared spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) to get a better understand concerning the catalytic activity behavior of Cu-CT catalyst. Different variable examined the catalytic activity of the samples obtained such as initial concentrations of dye, copper (Cu) loading, temperature and H 2 O 2 effect was investigated to enhance the MG conversion. CWPO experiments showed that 2.5% Cu-CT catalysts have the maximum catalytic activity during the degradation of MG dye. The presence of copper on CT support ameliorates the hydroxyl radicals in the reaction medium after the contact with H 2 O 2 thus enhanced the catalytic conversion of the CT pristine. The optimum conditions showing an important catalytic conversion of MG dye (95 %) at 2.5% of copper loading, 139.10 -3 mol.L -1 H 2 O 2, temperature of 40 °C and at pH 6.0 during 30 min as a reaction time.

Boosting catalytic wet-peroxide-oxidation performances of cobalt ferrite by doping with lanthanides for organic pollutants degradation

Up-to-date no study was reported dealing with cobalt ferrite-based catalysts for wet hydrogen peroxide oxidation (CWPO) of organic pollutants. In this respect, degradation of Rhodamine 6G-(Rh6G) was assessed by cobalt ferrites doped with lanthanum, gadolinium and dysprosium cations, for the first time. The ED-XRF proved the stoichiometry of catalysts. The XRD analysis confirmed the successful accommodation of the bulky rare-earth cations into the spinel matrix. The performance of the cobalt ferrite in CWPO process was categorically improved by doping. Thus, the Rh6G degradation efficiency after only 15 min of catalytic process was enhanced from 35.7% for the undoped cobalt ferrite to 92.8% for the gadolinium doped spinel. Moreover, the total organic compound (TOC) removal was boosted from 17% to 40% when cobalt ferrite was doped with lanthanum. The important boost in catalytic performance of doped samples was explained by a cumulative effect of reduction of size factor and the spinel phase purity as determined by Rietveld refinement of XRD patterns. Additionally, the performance of gadolinium containing catalyst was further improved by modeling and optimization of catalyst dose and hydrogen peroxide concentration, so the CWPO rate constant was enhanced from 1.611 × 10−1 up to 2.838 × 10−1 (min−1).

Highly efficient nitrogen-doped carbon nanotubes coated on paper-like sintered stainless steel fibers as metal-free structured catalyst for phenol degradation

Three types of carbon nanotubes coated on paper-like sintered stainless steel fibers (PSSF) were synthesized and applied for continuous catalytic wet hydrogen peroxide oxidation (CWPO) of phenol. The novel metal-free nitrogen-doped carbon nanotube-coated PSSF catalyst (N-CNTs/PSSF) was designed by direct chemical vapor deposition using melamine as solid precursor for the first time, and CNTs/PSSF and Fe2O3-deposited CNTs/PSSF (Fe-CNTs/PSSF) catalysts were synthesized for comparison. Characterization results showed that all the catalysts exhibited three-dimensional networks structure, with nanotubes wrapping on the stainless steel fibers successfully, and the N-CNTs showed distinct irregular corrugated morphology with nitrogen-doping level about 5.18 at.%. CWPO of phenol revealed that the N-CNTs/PSSF catalyst achieved favorable catalytic activity and highest stability during 100-h reaction (phenol and TOC conversions reached about 90% and 50%, respectively), while phenol conversions of CNTs/PSSF and Fe-CNTs/PSSF catalysts decreased over time to 72% and 58%, respectively. The N-CNTs/PSSF catalyst also showed the lowest Fe weight loss ratio (about 2.44 wt%) among the three catalysts. The favorable catalytic results of N-CNTs/PSSF can be ascribed to the synergistic effects of the strong affinity toward polar molecules of N-CNTs, as well as the enhancement in contact efficiency associated with three-dimensional networks structure of the PSSF.

Chemical and physical characterization of spent coffee ground biochar treated by a wet oxidation method for the production of a coke substitute

Coke production relies on the availability, cost and quality of coking coal. Depleting coking coal resources and environmental pressure force the metallurgical industry to search for alternative methods to produce coke. Waste spent coffee grounds (biomass) treated via hydrothermal liquefaction (HTL) is an energy-efficient method to produce biochar. In this study the use of HTL biochar as feedstock for the production of a coke substitute was investigated. Wet oxidation treatment of the prepared biochar samples was done with different wet oxidant hydrogen peroxide concentrations (5, 15, 30%). The biochar was treated for different time durations (0.5, 1, 2, 6 and 24 h) and at different temperatures (room temperature and 80 °C). Thereafter, the various samples were characterized and pyrolysed to obtain a coke substitute. Characterization of the various samples before and after thermal treatment was done using Fourier-transform infrared spectroscopy (FTIR), free swelling index, ultimate and proximate analysis, gross calorific value and compressive strength determination. The investigated characteristics of the produced coke substitute obtained from the pyrolysed biochar treated for 24 h with 30 vol% H2O2 at room temperature, showed the most promising results when compared to blast furnace coke.

Facile and Scalable Fabrication of CuO Nanoflakes with Excellent Catalytic Properties.

Well dispersed CuO nanoflakes were successfully achieved via a fast and self-heating route. The physical properties of the as-prepared products were analyzed by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), nitrogen adsorption-desorption measurements, transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Meanwhile, the catalytic activity and the catalytic advantage of CuO nanostructures are discussed with the help of first-order kinetics investigation for methylene blue degradation. It is found that self-heating in the reaction mixture and formation of cellular CuO network fully filled with oxygen bubble are mainly responsible for synthesis of CuO nanoflakes. Meanwhile, the as-obtained CuO nanoflakes possessed high specific surface area and exhibited high catalytic characteristics with wet hydrogen peroxide oxidation in methylene blue solution. The present work is likely to be favorable for taking full advantage of the catalytic activity of CuO nanostructures with high specific surface area for the wet hydrogen peroxide oxidation of dyes.

Preparation and properties of Cu-Ni bimetallic oxide catalyst supported on activated carbon for microwave assisted catalytic wet hydrogen peroxide oxidation for biologically pretreated coal chemical industry wastewater treatment

A microwave (MW)-assisted catalytic wet hydrogen peroxide oxidation (CWHPO) process was investigated to treat biologically pretreated coal chemical industry wastewater (CCIW) in this study. The activated carbon (AC) supported Cu-Ni bimetallic oxide catalyst was prepared by impregnation and precipitation method for MWCWHPO. The catalytic performance of the catalyst was investigated, and the main influencing factors were discussed. The results showed that the removal efficiencies of quinoline and total organic carbon (TOC) with catalyst prepared by impregnation method were 85% and 70%, respectively, and the removal efficiencies of quinoline and TOC with catalyst prepared by precipitation method were up to 95% and 76%, respectively. The utilization rate of hydrogen peroxide (H2O2) and the generation quantity of hydroxyl radicals were higher in the reaction process with the catalyst prepared by precipitation method than those with the catalyst prepared by impregnation method. The characterization of the catalyst showed that the smaller active component grains size, larger surface area and higher proportion of chemical adsorption oxygen were the main reason for the high catalytic efficiency. Furthermore, the optimized reaction conditions were: reaction temperature of 60 °C, microwave power of 500 W, and H2O2 initial concentration of 0.066 M. Moreover, the Cu-Ni bimetallic oxide catalyst is an efficient and stable catalyst in the degradation and mineralization of pollutants in the MWCWHPO process. The synthesized catalyst was verified to be attractive for use in the heterogeneous wet peroxide oxidation system under microwave irradiation.

Highly dispersed Fe3+-Al2O3 for the Fenton-like oxidation of phenol in a continuous up-flow fixed bed reactor. Enhancing catalyst stability through operating conditions

A highly dispersed Fe3+-Al2O3 catalyst (6 wt% Fe) was used for the catalytic wet hydrogen peroxide oxidation of phenol (1 g/L) in an up-flow fixed bed reactor (UFBR) under continuous operation. To enhance catalytic performance, three simple synthesis strategies were combined: two-stage impregnation of iron citrate, acid washing with CH3COOH and thermal treatment at 900 °C. Solid samples were characterized in depth by several techniques: N2 Physisorption, XRD, SEM–EDAX, TEM, TGA, PZC, TPD of pyridine, XPS and Mössbauer. Peroxidation experiments were performed in an UFBR over a wide range of operating parameters in order to evaluate their influence on phenol mineralization and catalyst stability. Under selected operating condition (T = 90 °C, Wcat = 20 g, QL = 1.2 mL/min and [H2O2]:[Phenol] = 16.8), complete phenol conversion and remarkable TOC reduction of 90% were achieved, with a high H2O2 consumption efficiency (η = 76%) and low Fe leaching (< 3 mg/L). After 70 h of usage at different steady state conditions, the catalyst retained high mineralization levels (XTOC> 70%) but the cumulative iron loss was calculated to be c.a. 20% of the initial Fe loaded in the UFBR. The catalyst was susceptible to leaching due to the accumulation of complexing intermediates such as carboxylic acids. However, acceptable iron leaching values (< 10 mg/L) were achieved when the reactor operating conditions were properly set (55% < XTOC> 80%). The presence of chelating by-products favored also the Fe redistribution inside the catalyst pellets. Nevertheless, catalyst decay in the long-term operation was mainly due to the occurrence and permanence of chelating organic acids. This process was specially promoted by the amphoteric character of the alumina-based catalyst. However, adsorbed species were promptly eliminated by calcination at 500 °C, recovering steady state conversion profiles.

Optimized CWPO phenol oxidation in CSTR reactor catalyzed by Al/Fe-PILC from concentrated precursors at circumneutral pH

The catalytic wet hydrogen peroxide oxidation of phenol catalyzed by an Al/Fe-PILC clay catalyst has been optimized in CSTR reactor. In order to get it more cost-effective, the process was optimized by simultaneous maximization of pollutant’s degradation and mineralization, whereas minimizing H2O2 consumption under very mild conditions of the covariates pH (4.5–11.3), temperature (5.0–25.9 °C) and input concentrations of phenol ranging 8.45–33.1 mg C/dm3 (expressed as TOC concentration); such a set of conditions resembled those typical in surface waters. A central composite statistical experimental design was developed, followed by optimization via response surface methodology with H2O2 dose (50.0–146.5% of the stoichiometric required for full oxidation) and catalyst concentration (0.5–3.0 g/dm3) as experimental factors. Covariate’s analysis showed that input TOC concentration and temperature were the most influencing ones, whereas pH did not result significant on any of the recorded responses within the assessed range (4.5–11.3). Optimal multi-response performance was achieved (65% of phenol degradation and 31% of TOC removal; 650 mg H2O2/dm3 in output stream) under stationary state with residence time of 135 min, room temperature (18 ± 1.0 °C) and neutral pH by using 1.77 g/dm3 of the clay-catalyst and tiny stoichiometric excess of the oxidizing agent (108% of the stoichiometric dose).

Effect of Calcination Temperature on Catalytic Performance of CeCu Oxide in Removal of Quinoline by Wet Hydrogen Peroxide Oxidation from Water

A facile citric acid-mediated complexation-calcination approach is reported in this paper to prepare the CeCu oxide composite with a porous structure that is highly efficient and durable for treating simulated quinoline wastewater by catalytic wet hydrogen peroxide oxidation (CWPO). As the results indicate, Cu species can be dissolved in CeO2 lattice to fabricate a solid solution. The calcination temperature is critical for an optimum catalyst structure and catalytic performance. As found in investigating the structure and catalytic performance of the CeCu oxide prepared at calcination temperatures ranging from 350 to 750 oC, the optimum temperature is 650 oC, at which a loose surface, a porous structure and considerable adsorbed surface oxide/hydroxyl oxide species are fabricated over the catalyst. This resultant catalyst also takes on the optimal performance with an oxidation conversion reaching 98% for quinoline, a removal efficiency of 80.6% for total organic carbon (TOC) and a low Cu2+ leaching value of 19.3 mg L-1. Besides, the high performance is maintained by the catalysts in a wide pH range of 5.1-10.5. This work generally provides an efficient way to design and fabricate the catalyst for CWPO reaction, which can also be applied in other reactions.

Environmentally Sustainable Fabrication of Cu1.94S-rGO Composite for Dual Environmental Application: Visible-Light-Active Photocatalyst and Room-Temperature Phenol Sensor

In the present study a novel Cu1.94S-rGO (rGO = reduced graphene oxide) composite is synthesized in an ecofriendly way and its application as photocatalyst and phenol sensor is explored. The extensive microscopic and spectroscopic characterization tools were used to confirm the structures and chemical vicinity of synthesized djurleite nanocomposite. This highly permeable mesoporous composite shows a direct band gap of 2.17 eV, which confers its semiconducting properties. Wet hydrogen peroxide catalytic oxidation method of photocatalysis was adopted here for the photodegradation of model cationic and anionic dyes, which result in 90.76% and 79.44% removal efficiencies, respectively, with the fixed catalyst dose and minimum additive of 0.55 mM hydrogen peroxide dose. The removal efficiency was improved significantly by the addition of a higher amount of hydrogen peroxide. Significant reusability is also observed here in both kinds of dye molecules and is contingent on its potential applicability. It also ex...

Enhanced heterogeneous wet hydrogen peroxide catalytic oxidation performance of fly ash-derived zeolite by CuO incorporation

Copper oxide incorporated fly ash-derived zeolite X (CuO/FAZ-X) was synthesized from solid waste coal fly ash by ion exchange with Cu2+ followed by calcination process. The synthesized materials were characterized by XRF, FTIR, SEM, EDX, and BET methods. In the application of the catalysts for wet peroxide oxidative decolorization of the model dye MB (Methylene Blue), the e ects of major parameters, such as CuOloading, initial H2O2 concentration, initial dye concentration, catalyst dosage, and pH, were investigated to assess the activity of the catalysts. In comparison with the activity of either fly ash-derived zeolite X (FAZ-X) or CuO, the combined catalyst (CuO/FAZ-X) showed an enhanced wet catalytic activity. Under the optimal condition (catalyst dose 250 mg/L, 100 ppm dye, pH = 6.8, 1 ml H2O2, and room temperature or 30C), the decolorization of MB was about 100% in 120 min by CuO/FAZ-X and only 31% and 44% by FAZ-X andCuO, respectively. Based on the decolorized products identi ed by HPLC-(-ESI)-TOFMS, the decolorization pathway of MB was proposed. Consequently, incorporation of CuO remarkably improved the catalytic activity of FAZ-X, such that CuO/FAZ-X emerged as a novel, reusable heterogeneous Fenton-like catalyst for oxidative decolorization of model dye MB. Thus, the present work demonstrates a simple and facile route for the conversion of waste coal fly ash into a valuable catalyst.

Treatment of printing and dyeing wastewater by catalytic wet hydrogen peroxide oxidation of honeycomb cinder as carrier catalyst

Under the condition of 35 °C, honeycomb cinder was used as the carrier, nickel as the active ingredient, impregnated for 2h, and calcined at 300 °C for 2h. The catalyst was used to Catalytic Wet Peroxide Oxidation of methylene blue simulated printing and dyeing wastewater. The effect of the amount of catalyst, the amount of catalyst, the reaction temperature and the reaction time on the treatment efficiency and the effect of the self-made catalyst on the simulated wastewater with different concentration gradient were studied in the experiment. The results showed that when the reaction conditions were H2O2 8ml/L, catalyst 12g/L and reaction time 1h, the degradation rate of methylene blue reached more than 77% for the wastewater with concentration ranging from 40 mg/L to 200 mg/L. In addition, at a temperature of 30 DEG C, the wastewater, the concentration was 80mg/L, degradation rate was up to 85.70%.

Synthesis of Polystyrene Beads for Hard-Templating of Three-Dimensionally Ordered Macroporosity and Hierarchical Texture of Adsorbents and Catalysts

Methods of polystyrene beads producing with properties appropriate for catalyst and adsorbent synthesis have been investigated. Hierarchical silicalite-1 and Fe-silicalite-1 with zeolitic MFI structure, as well as three-dimensionally ordered titania, silica, alumina and zirconia have been prepared by hard-templating method using polystyrene beads. The materials were characterized by X-ray diffraction, scanning and transmission electron microscopies, low-temperature nitrogen adsorption technique and mercury porosimetry. Developed meso- and macroporous structure of the templated materials facilitated the supply of macromolecular reactants to the material surface and reduced the negative effect of byproduct deposition, resulting in favored advantages of the materials in a wide range of processes: hydroconversion of heavy oil, wet hydrogen peroxide oxidation of organic substrates in water, photocatalysis and gas chromatographic analysis. The obtained results of the material applications showed their potential attractiveness as catalysts and adsorbents.