Forced Hydrolysis Research Articles

Study on the hydrolysis characteristics of polymeric aluminum chloride forced by fine bubbles and its key factors affecting the efficiency and capacity of forcing hydrolysis

Enhanced coagulation is an important way to remove natural organic matter and reduce disinfection by-products in traditional water treatment processes, in which the micromolecular organic matter that is difficult to be removed during conventional coagulation can be enhanced more conveniently by modulating the dominant Al species in the traditional metal salt coagulants (e.g., polymeric aluminum chloride, PACl). Based on the forcing hydrolysis characteristics of fine bubbles due to the adsorption of hydroxide ions on their surfaces, this study verified the adaptability of the forced PACl hydrolysis by fine bubbles under different operating conditions objectively and comprehensively. The morphological changes of PACl before and after forced hydrolysis by fine bubbles were characterized figuratively, and the evolution of the dominant Al species before and after forced hydrolysis by fine bubbles was reasonably elaborated. The experimental results showed that fine bubbles had the effect of forcing the hydrolysis of PACl with different degrees of alkalinity and modulating the dominant Al species. It was innovatively found that the mass transfer efficiency of the fine bubbles determined their efficiency in forcing PACl hydrolysis (Pearson's r = -0.9423) and the concentration of fine bubbles affected their capacity to force PACl hydrolysis (Pearson's r = 0.8189). At pH = 7 and an air flow rate of 20 mL/min, the DOC concentration of micromolecular organics and the DOC removal efficiency of total organics could be reduced by 0.54 mg/L and enhanced by 12.6 %, respectively, after forced PACl hydrolysis by fine bubbles. While deepening the mechanism of forced PACl hydrolysis by fine bubbles, the above results preliminarily verified the relevance and feasibility of modulating the dominant Al species through forced PACl hydrolysis by fine bubbles to improve the coagulation efficiency, which provided theoretical and data support for the construction of a fine bubble-enhanced coagulation process for drinking water treatment plants.

Formation of the hard-magnetic epsilon iron oxide phase from akaganéite nanoparticles

Elongated akaganéite (β-FeOOH) nanoparticles were prepared by a forced hydrolysis route using FeCl3·6H2O employing various urea concentrations.β-FeOOH nanoparticles stabilized within the SiO2matrix were annealed at different temperatures, ranging from 500 °C to 1300 °C. It was observed thatβ-FeOOH underwent a temperature-induced conversion toγ-Fe2O3and subsequently toϵ-Fe2O3. Due to theϵ-Fe2O3phase formation, the coercivity rapidly increased to 16 kOe for samples annealed at 900 °C and reached values up to 21.5 kOe when annealed at 1200 °C. At a higher temperature of 1300 °C, theϵ-Fe2O3phase transforms mainly into theα-Fe2O3phase, which causes the coercivity to rapidly drop to negligible values.

S. hispanica mucilage/ ZnO based films: Preparation, characterization, and potential application

The use of plastic for food packaging is a major contributor to environmental pollution. To address this issue, biopolymeric films have emerged as a potential alternative to plastic products commonly used in food packaging. These biopolymeric films can be enhanced with antimicrobial agents to make them more effective. This study aimed to develop and evaluate the properties of films made from Salvia hispanica mucilage and ZnO particles. The mucilage was obtained by filtering and drying seeds, while ZnO was synthesized using the forced hydrolysis of ZnC₄H₆O₄ and NaOH. The films were produced by combining the mucilage with varying concentrations of ZnO (0.1, 0.5, and 1.0%) using a casting method. Tests were conducted to evaluate the films' physical, chemical, and biological properties. X-ray diffraction analysis showed that ZnO was present, while scanning electron microscopy revealed the presence of C, O, and Zn elements. Fourier transform infrared spectroscopy confirmed the presence of S. hispanica mucilage. Thermogravimetric analysis showed that the films were thermally stable at temperatures below 225 °C. Dynamic mechanical analysis revealed that the 0.1% film had the best resistance compared to the 0.5% and 1.0% films. Finally, the study found that the antimicrobial activity of the films depended on the concentration, size, and morphology of the ZnO particles. In conclusion, further research is needed to create films that can effectively inhibit pathogenic bacteria growth in food and be a viable alternative to plastic for food packaging.

Antimicrobial Activity of ZnS and ZnO-TOP Nanoparticles Againts Pathogenic Bacteria.

This study aims to synthesize ZnS nanoparticles (NPs) and investigate their biocidal effects, along with those of ZnO-Trioctylphosphine (ZnO-TOP) NPs, on various pathogenic microbes. The NPs were synthesized via the polyol method using the forced hydrolysis of zinc acetate. They were characterized by XRD and TEM. The average sizes of ZnS and ZnO-TOP are 3.63 nm and 16.28 nm, respectively. The antimicrobial activities were assessed using agar-well diffusion, minimum inhibitory concentration (MIC), and biofilm inhibition. The results showed that ZnS and ZnO-TOP NPs have potent antimicrobial activity against all tested pathogen microbes. A zone of maximum inhibition (ZMI) of 20±0.54 and 22±0.26 was observed in the case of ZnS for Acinetobacter baumannii and Candida albicans, respectively. For ZnO-TOP, a ZMI of 20±0.15 and 20±0.19 is obtained for Pseudomonas. aeruginosa ATCC 27853 and A. baumannii, respectively. Percentages of biofilm inhibition at 128 μg/ml were notably high for Enterococcus faecalis (96.83 % with ZnO-TOP and 91.17 % with ZnS) and Staphylococcus aureus (87.27 % with ZnO-TOP and 76.37 % with ZnS). The results suggest that ZnS and ZnO-TOP nanoparticles have promising potential as effective antimicrobial agents, especially against biofilm-forming pathogens, indicating their potential for future use in treating microbial infections.

Effect of Calcination Temperature on Crystalline phase and Grain size of ZnO Particles

In today's technology, ZnO as a semiconductor, has emerged as a leading candidate in green environmental management systems, owing to its strong oxidation ability, good photocatalytic properties, and large free-exciton binding energy. ZnO is a costeffective, stable, and high photocatalytic material with good electrical properties and light transmittance, making it useful for various applications such as solar cells, photocatalysts, and electrical equipment. ZnO, being a photocatalyst, can be used for environmental clean-up efforts such as air purification, water purification, and deodorization. In this study, the zinc oxide (ZnO) was synthesised with a forced hydrolysis method and characterised by different characterization techniques. X-ray diffraction (XRD) was used to investigate the change in phase and crystal structure of ZnO particles at different calcination temperatures. Moreover, the average crystallite size of the particles was calculated at various calcination temperatures, using Scherrer equation. Also Scanning Electron Microscopy (SEM) used to image the surface morphology and size of the particles and it is found that the calcination temperature had a significant effect on the morphology of the particles. Additionally, differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) were used to observe the material transitions and changes in mass as the temperature increased.

A study of quinclorac degradation during thermal and forced hydrolysis and soil photolysis

A study of quinclorac degradation during thermal and forced hydrolysis and soil photolysis

Development of FexOy particle onto bacterial cellulose network by forced hydrolysis and its electrical conductivity

FexOy particle and bacterial cellulose composite sheet was successfully prepared by forced hydrolysis. The presence of Fe3+ ions in bacterial cellulose suspension significantly provided the positive charge due to electrostatic force as reported by Zeta potential. With the pH of 12 of bacterial cellulose suspension, particle was nucleated between bacterial cellulose networks. Fourier transform infrared exhibited Fe-O stretching. X-ray diffraction reported that the mixture of Fe2O3 and Fe3O4 was existed onto bacterial cellulose composite. Scanning electron microscope reported that FexOy particle was randomly distributed in bacterial cellulose network. Intensity of Fe was qualitatively observed by energy dispersive analysis. With the existence of FexOy particle, the composite illustrated the inferiority of thermal stability of 150℃. Furthermore, it was noted that the resistivity was reduced with respect to increment of FexOy particle, suggesting that electrical conductivity was then enhanced. It was remarkable to note that FexOy particle and bacterial cellulose composite sheet prepared from forced hydrolysis showed the excellent properties as a candidate for flexible electrode.

A Review on Gallium Oxide Materials from Solution Processes.

Gallium oxide (Ga2O3) materials can be fabricated via various methods or processes. It is often mentioned that it possesses different polymorphs (α-, β-, γ-, δ- and ε-Ga2O3) and excellent physical and chemical properties. The basic properties, crystalline structure, band gap, density of states, and other properties of Ga2O3 will be discussed in this article. This article extensively discusses synthesis of pure Ga2O3, co-doped Ga2O3 and Ga2O3-metal oxide composite and Ga2O3/metal oxide heterostructure nanomaterials via solution-based methods mainly sol-gel, hydrothermal, chemical bath methods, solvothermal, forced hydrolysis, reflux condensation, and electrochemical deposition methods. The influence of the type of precursor solution and the synthesis conditions on the morphology, size, and properties of final products is thoroughly described. Furthermore, the applications of Ga2O3 will be introduced and discussed from these solution processes, such as deep ultraviolet photodetector, gas sensors, pH sensors, photocatalytic and photodegradation, and other applications. In addition, research progress and future outlook are identified.

Co-coagulation of micro-nano bubbles (MNBs) for enhanced drinking water treatment: A study on the efficiency and mechanism of a novel cleaning process

MNBs (Micro-nano bubbles) are widely used in cleaning processes for environmental treatments, but few studies have examined the interaction of MNBs with coagulation. In this study, a novel process, i.e., MNBs-coagulation, was developed for enhanced drinking water treatment. The humic acid (HA) removal efficiency was used to evaluate the effectiveness of MNBs-coagulation for drinking water treatment. The hydrolysis component ratio of polymeric aluminum chloride (PACl) with and without MNBs, the complexation strength of HA and PACl, and flocculent functional group characterization were used to analyze the mechanism of the MNBs-coagulation process to enhance drinking water treatment. The results of a Jar test showed that the MNBs-coagulation process could improve the removal efficiency of HA (up to a 27.9% increase in DOC removal). In continuous-flow experiments to remove HA, MNBs-coagulation can increase the removal efficiency of UV254 by about 26.5% and with no significant change in turbidity. These results are attributed to the inherent hydroxyl radical generating properties of MNBs, the forced hydrolysis of PACl by MNBs to increase the Alc percentage, and the ability of MNBs to increase the complexation strength of HA with PACl. At the same time, the MNBs-coagulation process has a strong anti-interference ability, almost no interference from anions and cations such as Cl−, SO42− and Ca2+, and has a good performance in natural surface water. In summary, MNBs-coagulation has strong potential for practical applications to enhance the efficiency of drinking water treatment.

Effects of Formation Pathways and Bromide Incorporation on Jarosite Dissolution Rates: Implications for Mars

AbstractThe dissolution rates of jarosite can constrain the duration of aqueous activities on Mars. To date, few studies have considered the influences of formation pathways and anion substitutions on jarosite dissolution rates. Here, we investigated how the formation pathways (Fe(II)‐oxidation and Fe(III)‐forced hydrolysis) and incorporation of bromide influence the dissolution rates of K‐jarosite under eight aqueous conditions combining T (277 K, 298 K, and 323 K) and αw (0.35, 0.75 and 1), except for 277 K−0.35αw. The results show that jarosite dissolution rates are primarily influenced by aqueous T‐αw conditions. Formation pathways and Br contents are secondary factors and only become notable under low T (277 K) and low αw (0.35) conditions. Taking the jarosite formation pathways and Br incorporation into account, the maximum lifetime of jarosite may be slightly longer than that of the halogen‐free counterparts formed via Fe(III)‐forced hydrolysis. Jarosite of the Burns Formation (Meridiani Planum) and the Pahrump Hills member (Gale Crater) are likely formed via Fe(II)‐oxidation and halogen‐bearing. Their estimated field lifetime (∼150 μm–1 mm particles) in low‐T groundwater may last for hundreds of thousand years to a few million years. Jarosite in the Vera Rubin Ridge would share a similar lifespan if low‐T solutions account for jarosite formation and subsequent interactions; otherwise, interactions with hydrothermal fluids (∼100°C) would substantially shorten the jarosite lifetime. We conclude that Martian jarosite may survive continuous aqueous interactions for up to a few million years, indicating an extended duration of aqueous environments than previously thought.

QUANTIFICATION OF PREGABALIN AND ETORICOXIB COMBO IN TABLETS AND BULK WITH DEVELOPED RP-HPLC METHOD: STABILITY INDICATING FEATURE ASSESSMENT

This investigation reports a stability indicating HPLC method to quantify Pregabalin (PGBN) and etoricoxib (ERCB) in tablets form and bulk form. The PGBN and ERCB were quantified on Thermo C18 column with Orthophosphoric acid (0.1%), and methanol 60:40 vol/vol ratio was employed as mobile phase. The amounts of PGBN and ERCB were enumerated by detector fixed at 236 nm. The procedure demonstrated reasonable linearity for PGBN with R2 = 0.9998 in the quantity scale 37.5 to 112.5 µg/ml, and for ERCB with R2 = 0.9999 in the quantity scale 30 to 90 µg/ml. The LOD as well as LOQ for PGBN are 0.201µg/ml 6 0.670 µg/ml and for ERCB are 0.106 µg/ml 6 0.355 µg/ml. The RT’s for PGBN was 2.636 min and ERCB was 5.607 min and whole analysis time was 8 min. Stability degradation experiments were used to establish the method's capacity to indicate stability indicating. The conditions include acid forced hydrolysis, thermal forced degradation, alkali forced hydrolysis, oxidative forced degradation and photo forced degradation conditions. Detection as well as quantification of PGBN and ERCB was unaffected by the degradants.

Role of surface chemistry of activated carbon for anchoring iron particles by forced hydrolysis and evaluation of iron-loaded adsorbents for Cr (VI) adsorption

ABSTRACT This research aimed to assess the role of granular activated carbon (GAC) functional groups for anchoring iron particles by forced hydrolysis and the effect of iron-loaded GAC for the adsorption of Cr (VI). First, to modify the surface chemistry of the GAC, the adsorbent was treated by oxidation, heating, and ammonia soaking. Next, the anchorage of iron on raw and modified GAC by forced hydrolysis was conducted. Subsequently, adsorbents were characterized, and adsorption tests were performed at pH 6 and 25°C. Findings revealed that the incorporation of acid functional groups on the GAC surface by oxidation allowed an iron anchoring (1.5%) higher than the heat-treated GAC (0.2%). Besides, forced hydrolysis treatment significantly improved the Cr (VI) adsorption capacity at equilibrium concentrations lower than 150 mg/L. Heat-treated GAC with iron achieved the best Cr (VI) uptake capacity (57 mg/g) and the fastest adsorption kinetics of the studied adsorbents. Cr (VI) desorption (98%) from the best adsorbent (iron-loaded and heat-treated GAC) was attained with a 0.1 N NaOH-NaCl solution, suggesting an adsorption mechanism mainly by physical attraction. In conclusion, the surface chemistry of GAC plays a significant role in the anchorage of iron particles, and iron particles improve Cr (VI) adsorption.

Forced hydrolysis of FeCl3 solutions in the presence of guanylurea phosphate

The effects of guanylurea phosphate on the properties of precipitates formed by forced hydrolysis of FeCl3 solutions were investigated using a combination of XRD, 57Fe Mössbauer, FT-IR and FE SEM analyses. Samples were prepared at 160 °C by varying the concentration of FeCl3 solutions and the amount of guanylurea phosphate added. This study showed that this simple method can be used to prepare giniite (Fe5(PO4)4(OH)3‧2 H2O) as a single phase with a variety of particle shapes. Three main phases, giniite, akaganeite (β-FeOOH) and hematite (α-Fe2O3), were obtained, where the exact phase composition of precipitates depended on the chemical conditions in the starting solutions. The optimum conditions for the formation of different dendritic nano/microstructures were 2‧10−3 and 5‧10−3 M FeCl3 solutions containing guanylurea phosphate. This proposed method of giniite synthesis has potential in the further investigation of the formation nature of dendritic nano/microstructures.

Surface-modified ZrO2 nanoparticles with caffeic acid: Characterization and in vitro evaluation of biosafety for placental cells

The toxicity of hybrid nanoparticles, consisting of non-toxic components, zirconium dioxide nanoparticles (ZrO2 NPs), and caffeic acid (CA), was examined against four different cell lines (HTR-8 SV/Neo, JEG-3, JAR, and HeLa). Stable aqueous ZrO2 sol, synthesized by forced hydrolysis, consists of 3–4 nm in size primary particles organized in 30–60 nm in size snowflake-like particles, as determined by transmission electron microscopy and direct light scattering measurements. The surface modification of ZrO2 NPs with CA leads to the formation of an interfacial charge transfer (ICT) complex followed by the appearance of absorption in the visible spectral range. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The ZrO2 NPs and CA are non-toxic against four different cell lines in investigated concentration range. Also, ZrO2 NPs promote the proliferation of HTR-8 SV/Neo, JAR, and HeLa cells. On the other hand, hybrid ZrO2/CA NPs induced a significant reduction of the viability of the JEG-3 cells (39 %) for the high concentration of components (1.6 mM ZrO2 and 0.4 mM CA).

Photocatalytic Degradation of Pharmaceuticals through Bulk and Mesoporous g-C3N4/TiO2 Systems

Background: In recent years, pharmaceutical pollutants have emerged as a growing threat to the environment. To mitigate this situation, heterogeneous photocatalysis has been considered a promising advanced oxidation technology, where TiO2-based systems have exhibited outstanding efficiency in the degradation of organic compounds. Objective: In this work, we have studied the photocatalytic performance of the coupled g-C3N4/TiO2 system in the degradation of the pharmaceuticals tetracycline, ciprofloxacin, and ibuprofen. Moreover, the effect of the graphitic carbon nitride (g-C3N4) was examined through the study of two different samples, a bulk g-C3N4 prepared from the direct calcination of melamine and a mesoporous g-C3N4 synthesized through a nanocasting process using SBA-15 silica as hard template. Methods: The hybrid photocatalysts were prepared by forced hydrolysis of titanium isopropoxide using two g-C3N4 samples, a bulk material and a mesoporous one. The samples were characterized by X-ray powder diffraction (XRD), Diffuse Reflectance Spectroscopy (DRS), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and N2 adsorption-desorption measurements. The photocatalytic activity was examined through the degradation of tetracycline, ciprofloxacin, and ibuprofen under simulated solar irradiation. Results: The textural properties of g-C3N4 play a preponderant role in the photoactivity of the g- C3N4/TiO2 system. In this sense, high dispersion of the TiO2 nanoparticles could be obtained using a mesoporous g-C3N4 sample. All hybrid photocatalysts exhibit higher degradation rates than the pristine materials, including bare TiO2. In this regard, the samples with 1 wt.% g-C3N4 attained the highest photocatalytic performance in the degradation of tetracycline, ciprofloxacin, and ibuprofen. Conclusion: The coupling of TiO2 with graphitic carbon nitride leads to the formation of hybrid photocatalysts with outstanding photoactive properties in the degradation of pharmaceutical pollutants. In this way, the g-C3N4/TiO2 samples can be considered as excellent photocatalysts for the degradation of organic pollutants.

Tuning Properties of Cerium Dioxide Nanoparticles by Surface Modification with Catecholate-type of Ligands.

Cerium dioxide (CeO2) finds applications in areas such as corrosion protection, solar cells, or catalysis, finding increasing applications in biomedicine. This work reports on surface-modified CeO2 particles in order to tune their applicability in the biomedical field. Stable aqueous CeO2 sol, consisting of 3-4 nm in size crystallites, was synthesized using forced hydrolysis. The coordination of catecholate-type of ligands (catechol, caffeic acid, tiron, and dopamine) to the surface-Ce atoms is followed with the appearance of absorption in the visible spectral range as a consequence of interfacial charge-transfer complex formation. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The synthesized samples were characterized by X-ray diffraction analysis, transmission electron microscopy, and nitrogen adsorption-desorption isotherms. The ζ-potential measurements indicated that the stability of CeO2 sol is preserved upon surface modification. The pristine CeO2 nanoparticles (NPs) are nontoxic against pre-osteoblast cells in the entire studied concentration range (up to 1.5 mM). Hybrid CeO2 NPs, capped with dopamine or caffeic acid, display toxic behavior for concentrations ≥0.17 and 1.5 mM, respectively. On the other hand, surface-modified CeO2 NPs with catechol and tiron promote the proliferation of pre-osteoblast cells.

Synthesis of cisplatin encapsulated Zinc oxide nanoparticles and their application as a carrier in targeted drug delivery

Cisplatin is a frequently used anticancer drug that has been developed as the first platinum-based anticancer drug. The cis configuration enables the coordination complex to be covalently binding to one or two DNA strands and thus cross-linking the DNA strands, causing the cells to die in a programmed manner. Cisplatin is administered as an IV infusion in saline solution for medication of solid malignity. Anticancer drugs usually have a variety of side effects, but an encapsulation of the drug in a suitable host material minimizes the side effects while improving the efficacy of the drug due to its slow release only at the target. The aim of this research is to develop a simple, but effective mechanism for the preparation of porous zinc oxide nanoparticles (PZnO NPs) using the forced hydrolysis method reaction of zinc acetate dihydrate with deionized water in diethylene glycol (DEG) media. This synthesized PZnO NPs were then characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), Fourier Transform Infrared Spectroscopy (FT-IR), Particle Size Analysis and Powder X-Ray Diffraction (PXRD). The encapsulation of cisplatin within the porous zinc oxide nanoparticles was confirmed by X-ray Fluorescence (XRF), SEM, EDX, and FT-IR studies. Our results show that the synthesized nanoparticles have the hexagonal wurtzite structure as confirmed by PXRD. The average particle size as determined by light scattering is 52.4 ± 0.1 nm SEM images show porous spherical morphology with aggregated particles. XRF data of the cisplatin encapsulated product show a Pt: Cl ratio of 1:2 showing cisplatin encapsulation without any fragmentation or other chemical change. The presence of NH3 in the encapsulated product is also apparent from FT-IR data. The encapsulation of the anti-cancer drug cisplatin to PZnO NPs and its pH dependence on the release of the drug from PZnO NPs was studied by measuring the amount of Pt released as a function of the time which was done using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) at λmax 265.94 nm. The encapsulation efficiency of Cisplatin into PZnO NPs was found to be 50.52%. The percentage of Cisplatin released from PZnO NPs during the first 7 hours was < 6.30% in the acetate/phosphate buffer at pH 4.0, 5.0, 6.0, 7.0 and 8.0. The maximum release of 8.64% was observed at pH = 6.0 after 24 hours.

Separation and Simultaneous Quantitation of Montelukast Sodium and Ebastine in Tablets by using Stability-Indicating Liquid Chromatographic Method

Objectives: A precise, accurate and selective stability-indicating reverse&nbsp;phase high performance liquid chromatographic assay method has been&nbsp;developed for the simultaneous quantitative determination of Montelukast&nbsp;sodium and Ebastine in tablets. Methods: The chromatographic separation&nbsp;of drugs was attained by using Hypersil octadecyl silane C18 (250 x 4.6&nbsp;mm, 5μm) column at room temperature. The composition of mobile phase&nbsp;was methanol, acetonitrile and 0.02M ammonium acetate buffer (pH 5.5&nbsp;adjusted with dilute acetic acid) in the ratio of 80:15:05 v/v/v and flow rate&nbsp;of mobile phase 1.0 ml/min with isocratic elution. The signal of eluents&nbsp;was observed at 244 nm by using diode array detector. Results: The retention&nbsp;time of Montelukast sodium and Ebastine were found to be 4.28 min&nbsp;and 6.63 min, respectively. The linearity ranges for both drugs were found&nbsp;to be 10-50 μg/ml and the percent recoveries were found to be 99.16%&nbsp;and 100.12% for Montelukast sodium and Ebastine respectively. The drug&nbsp;substances and drug products were treated with various forced degradation&nbsp;conditions like acid hydrolysis, alkali hydrolysis, oxidative degradation,&nbsp;thermal degradation and photolytic degradation. The degradants were efficiently&nbsp;separated from the drugs by using optimized chromatographic conditions.&nbsp;The developed method was validated as per recommendation parameters&nbsp;of International conference on harmonization guidelines Q2(R1).&nbsp;Conclusion: The validation parameters indicate that the drug substances&nbsp;were efficiently separated from its degradants and developed method can&nbsp;be routinely applied for the simultaneous quantitative determination of&nbsp;Montelukast sodium and Ebastine in combined tablet formulation in the&nbsp;quality control laboratory.

Preparation and Photo-catalytic Activity of Cu-Supported Nano-TiO2

Cu-supported nano-TiO2 catalyst was prepared by forced hydrolysis method under mild condition. The morphology, composition and optical absorption properties of the samples were characterized by means of scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and UV-Vis diffuse reflectance spectroscopy (UV-VIS DRS). Visible photocatalytic activity of the samples was investigated by photocatalytic degradation experiment on methyl orange. The results indicated that nano-TiO2 was about 20nm in size with the main form of anatase, and photo response range was significantly broadened after it was loaded on the surface of Cu. The sample possessed high visible light catalytic activity, with the degradation rate of methyl orange reaching 94% under simulated natural light.

Synthesis and characterization of nano α-Fe2O3/Mn2P2O7 for photocatalytic decomposition of p-xylene: using Box-Behnken design

α-Fe2O3/Mn2P2O7 photocatalyst was synthesized by forced hydrolysis and reflux condensation (FHRC) method. In order to fully evaluate of the structure, chemical composition and morphology of synthesized composite, various analyses such as XRD, FT-IR, BET, EDX, SEM were applied. In this research, para-xylene was selected as the model substance for photocatalytic reactions to evaluate catalytic ability. To investigate the effect of parameters and selecting the optimum condition for the understudied process, Box Behnken Design (BBD) due to the Response Surface Methodology (RSM) was performed. For this purpose, catalyst concentration, hydrogen peroxide concentration, initial p-Xylene concentration and, pH was selected as important and effective variables. Results showed that the optimized degradation efficiency was close to 96.68% within 90 min. Based on the results, it was found that the initial concentration of p-Xylene had the greatest effect on the removal of contamination. Moreover, it was determined that the photocatalytic efficiency of the synthesized composite is more favorable than the non-supported α-Fe2O3.