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The possible use of mustard seeds functionalized with tri-octylamine (TOA) as a novel adsorbent (TOA-M)-BR was used successfully to remove Cr(VI) from sulfate media. The effectiveness of various factors such as, effect of H2SO4 concentration, liquid-to-solid (V/m) ratios, contact time, initial concentrations of Cr(VI), in addition to temperature were investigated. At the optimum conditions (V/m 1.0 Lg−1, H2SO4: 2.5 M, T: 25±1 °C), (%R) was >99% and the maximum uptake reached to 22.67 mg g−1. Cr(VI) uptake process followed the pseudo-first-order rate and thermodynamic parameters were estimated. The obtained data have illustrated that the adsorption process was feasible, spontaneous, and endothermic in nature. The adsorption equilibrium compliance with Langmuir isotherm. The results exhibited that, Cr(III) is not adsorbed under the operating conditions that lead to separate Cr(VI) and Mo(VI) from some fission products such as Eu (III), La(III), Ce(IV), and Y(III) with impregnated (TOA-M)-BR with considerable values of separation efficiency. Both Mo(VI) and Cr(VI) were adsorbed with an efficiency of 90 and 70%, respectively.

In this study, the separation of lanthanides from phosphate ore using oxalic acid (C2H2O4), tartaric acid (C4H6O6), lactic acid (C3H6O3), sulfuric acid (H2SO4) and hydrochloric acid (HCl) was investigated. The ore was characterized before and after leaching processes by X-ray fluorescence (XRF), Scanning electron microscope (SEM), X-ray powder diffraction (XRD), and Fourier transform infrared (FTIR). The different parameters affect the leaching rate such as leaching time, acid concentration, liquid/solid ratios, temperature, and leaching kinetics were studied. The optimal leaching conditions were determined as 0.4 M C2H2O4, 2.5 M C4H6O6, 1.8 M C3H6O3, 2.0 M H2SO4, and 3.0 M HCl, with a liquid/solid (L/S) mass ratio of 6/1 C2H2O4, 8/1 for both C4H6O6 and C3H6O3, 5/1 for both H2SO4 and HCl at 30 °C, agitation rate ≈ 350 rpm and particle size ≈ 144.8 μm. Under these optimum conditions, the recovery percentage (%R) was 42.8% (for C2H2O4), 93.2% (for C4H6O6), 89.1% (for C3H6O3), 89.3% (for H2SO4), and 74.6% (for HCl). SEM and FTIR characterizations for the residue were investigated. Experimental data reveal that the leaching processes are fitted by chemical reaction models for C2H2O4 and C3H6O3, and by diffusion-reaction model for C4H6O6, H2SO4, and HCl. The activation energies for these models were estimated to be 43.3, 30.33, 45.8, 31.3, and 38.6 kJ/mol for C2H2O4, C4H6O6, C3H6O3, H2SO4, and HCl, respectively. All data were confirmed and explained by XRD, FTIR, and SEM studies.

The tanning industry causes great damage and pollution to the environment. It generates tanning effluents and solid waste which, without pretreatment, discharged directly into the environment. Beam-house operations are among the important process of this industry which generates the biggest amount of toxic effluents. These wastes are considered as the most odious materials in the leather industry. The effluent is characterized by alkaline pH value, high loads of oil&grease, sulfides, total suspended solids, chemical oxygen demands and biological oxygen demands. Integration of chemical coagulation using ferric chloride aided with lime and down flow hanging non-woven (DHNW) reactor was applied in the present study. Coagulation was performed using a continuous coagulation reactor (CCT). The DHNW was packed with non-woven poly ethylene terephthalate (PET) fabric produced from waste plastic bottles. The efficiency of the integrated treatment system was assessed using the reduction of sulfide, chemical and biological oxygen demands (COD & BOD), total Kjeldahl nitrogen (TKN) and total suspended solids (TSS). Residual concentrations of COD, BOD and TSS in the CCT effluent were 985, 440 and 25 mg/L (96.1%, 85.2% and 99.3% removal), respectively. The effluent of CCT reactor was feed to the DHNW reactor. Concentrations of COD, BOD and TSS were 145, 55 and 4 mg/L, respectively in the final treated effluent. While, the sulfide concentration had been greatly reduced to 0.5 mg/L. With respect to the parameters studied, the treated effluent might meet the National regulatory standards for discharging into the sewerage systems.

The presence of dyes in industrial wastewater is a serious problem that hazards the surrounding environment. Therefore, this work investigates the removal of a binary dye system composed of Methylene Blue (MB) and Crystal Violet (CV) using an innovative composite (cotton fiber–graphene oxide (C–GO)). The simultaneous determination of the concentrations of the dyes in the binary system is a challenge. Thus, a new method was investigated to simultaneously detect the concentration of the dyes in the binary system using first-order derivative UV spectra to avoid the complex overlap of the maximum peaks in the original zero-order absorption spectra. Different parameters affecting the filter sorption mode, such as the concentration of the dyes, the dose of the (C–GO) composite, the dose of NaCl, flow rate, temperature, and pH, were investigated. The data obtained showed high adsorption efficiency for the binary dye system (>99%). This was approved based on the maximum sorption capacity (Q°) value obtained for the Langmuir model. Furthermore, this technique was developed, evaluated and applied to treat real industrial waste. The obtained data showed that the C–GO composite was highly efficient in treating industrial wastewater containing such dyes when a sufficient quantity is used. Therefore, it can be used as a promising adsorbent for such dyes in wastewater treatment processes.

Dual inhibition of topoisomerase (topo) II and FLT3 kinase, as in the case of C-1311, was shown to overcome the shortcomings of using topo II inhibitors solely. In the present study, we designed and synthesized two series of pyrido-dipyrimidine- and pseudo-pyrido-acridone-containing compounds. The two series were evaluated against topo II and FLT3 as well as the HL-60 promyelocytic leukemia cell line in vitro. Compounds 6, 7, and 20 showed higher potency against topo II than the standard amsacrine (AMSA), whereas compounds 19 and 20 were stronger FLT3 inhibitors than the standard DACA. Compounds 19 and 20 showed to be dual inhibitors of both enzymes. Compounds 6, 7, 19, and 20 were more potent inhibitors of the HL-60 cell line than the standard AMSA. The results of the in vitro DNA flow cytometry analysis assay and Annexin V-FITC apoptosis analysis showed that 19 and 20 induced cell cycle arrest at the G2/M phase, significantly higher total percentage of apoptosis, and late-stage apoptosis in HL-60 cell lines than AMSA. Furthermore, 19 and 20 upregulated several apoptosis biomarkers such as p53, TNFα, caspase 3/7 and increased the Bax/Bcl-2 ratio. These results showed that 19 and 20 deserve further evaluation of their antiproliferative activities, particularly in leukemia. Molecular docking studies were performed for selected compounds against topo II and FLT3 enzymes to investigate their binding patterns. Compound 19 exerted dual fitting inside the active site of both enzymes.

The scarcity of water resources and climatic changes are among the factors that facing many countries of the world. Also, conflicts between some countries over water resources are a new threat which could lead to a loss of large quantities that were received by these countries. Therefore, wastewater treatment and reuse provide an unconventional water resource. The treatment and reuse reduce pollution of drinking water resources as a result of discharging untreated wastewater, thereby reducing the spread of epidemic diseases. Decentralized low-cost technologies that do not consume a lot of energy are one of the important solutions that draw the attention of decision-makers in many countries. The integration of the upflow anaerobic sludge blanket reactor and different posttreatment systems such as constructed wetlands, downflow hanging sponge and downflow hanging nonwoven fabric reactor.

Due to the harmful effects of some biological and environmental hazard, many studies were directed to investigate advanced devices with high sensitive and fast detection. Biosensor is a device by which a readable information was produced at interaction of biological molecule with an electronic ingredient and has been highly developed to be used in a variety of applications using different bioreceptor, using transducers with different detection mechanisms and the most attractive use of nanomaterials in improving the performance of nanobiosensors. Nanomaterials have attracts great interest in improving and manufacture of biosensors. Where, the marked surface area of the nanosize particles enhances the immobilization of various biological molecules on its surface. These functionalized nanomaterials improve the detection and the strength of different signals. Moreover, this review discusses some types of biosensors that used in different biological and environmental applications and the effect of the nanomaterials on the enhancement of their performance.

New Nanocopper ferrocyanide-silica nanoparticles (SiO2-CuFe-CN) NPs were synthesized by co-condensation (one-pot) procedure; the prepared composite were characterized using FTIR, XRD, EDS and SEM. The sorption affinity of nanocopper ferrocyanide-SiO2 materials towards 134Cs and 60Co radioisotopes from aqueous and nitrate medium were extensively studied. The factors affecting the sorption process such as mixing time, pH, metal ion concentrations and temperature were conducted. The experimental isotherm data were found to fit with both Langmuir and Freundlich isotherms. The thermodynamic parameters were evaluated. The results obtained proved that (SiO2-CuFe-CN) NPs is a promising material for the remediation of low level radioactive waste solutions contains 134Cs, 60Co, 99Mo and 90Sr of relatively low nitric acid concentration. The results obtained in the application section reveals that (SiO2-CuFe-CN) NPs gives high selective sorption of 99Mo radioisotope over other radioisotopes from 0.01 M HNO3.

Cotton fiber–graphene oxide (C–GO) composite with high adsorptive properties towards the cationic dye, crystal violet (CV), was successfully fabricated by simple mixing of cotton fiber and GO in aqueous solution using a homogenizer. The as-prepared composite was characterized using TEM, SEM, LOM, XRD, FTIR, Raman and TGA. The characterization indicated that the formation of a homogeneous composite occurred via adequate mixing of the cotton fiber and GO. The fine structure of the obtained composite was successfully used in two adsorption techniques, namely batch adsorption and filter adsorption. Various parameters affecting batch adsorption, such as contact time, dye concentration, composite dose, NaCl dose, temperature and pH were investigated. In the filter adsorption mode, dye concentration, composite dose, NaCl dose, temperature, flow rate and pH were studied. A comparison study between the two techniques, i.e., batch adsorption and filter adsorption, are reported. The filter adsorption technique shows higher adsorption efficiency than the batch one, which was evident from the maximum adsorption capacity (Q°) values, obtained from the Langmuir isotherm. Further, the filter technique was developed and evaluated. This was achieved by regeneration, scaling-up and, finally, using another model of cationic dye (methylene blue).

Extraction of V(V) and Cr(III) from acidic sulfate leach liquors of ilmenite using 0.4 mol/L Aliquat 336 chloride in kerosene was carried out. Different parameters affecting the extraction process such as equilibrium time, sulfate concentration, Aliquat 336 concentration, equilibrium pH and the extraction temperature were investigated. Extraction of V(V) and Cr(III) by Aliquat 336 involved anion exchange mechanism, and the extracted species are [(VO2SO4)R4N]org at low equilibrium pH for V(V) and [R4N-Cr(OH)4]org at high equilibrium pH for Cr(III). Calculated thermodynamic parameters show that the extraction process is endothermic reaction for V(V) and exothermic for Cr(III). Also, calculated values of ΔGex and ΔSex indicate that the extraction reactions of V(V) and Cr(III) proceed as non-spontaneous reaction is more random. V(V) and Cr(III) were stripped, precipitated, separated and calcined at 500 °C for 2.0 h to produce the corresponding oxide in pure form after rinsing and drying.

In this work, the removal of gadolinium and cobalt ions using Dowex HCR-S/S resin was studied. Batch-mode kinetic and equilibrium studies have been carried out. The effect of solution pH, shaking time, initial metal ion concentrations, resin dosage and temperature has been investigated. Equilibrium data were analyzed by sorption isotherm models. The results of sorption experiments indicate that the monolayer capacities of Gd(III) and Co(II) at equilibrium are 66.0 and 69.4 mg/g, respectively. The results of kinetic models showed that the pseudo-second-order kinetic model was found to correlate with the experimental data well. It was found that the amount of ions sorbed onto the resin increased with increasing temperature; this indicates the endothermic nature of the sorption process. It was concluded that resin has an efficient sorption capacity compared to many sorbents.

This work describes the extraction and separation of Mn(II), Co(II), Ni(II) and Li(I) from the leach liquor of mixed lithium ion batteries using 0.04 M Na-CYANEX272. Before the extraction step, elimination of some impurities such as Fe(III), Cu(II) and Al (III) was carried out by 20% Acorga M5640 in kerosene with agitation for 5 min at 30 °C at equal phase ratio of unity. The effects of the different parameters affecting the extraction rate, such as mixing time, pH, extractant concentration and temperature, were separately investigated. The obtained results indicate that the extraction behavior of the investigated metal ions depends on the pH value, where 91.2% Mn(II), 89.3% Co(II) and 95.6% Ni(II) were extracted at pH 3.5, 5.0 and 8.0, respectively, while the extraction of Li(I) was almost constant regardless of the pH value. Mn(II), Co(II) and Ni(II) were extracted in the organic phase as (MA 2 •3HA) (org) while Li(I) was extracted as (MA•2HA) (org) . The thermodynamic parameters were calculated by applying Van't Hoff equations. A complete stripping and precipitation from the organic and aqueous phases could be achieved with different stripping and precipitating agents. Precipitates of Mn(II), Co(II), Ni(II) and Li(I) with purity > 99% could be obtained under the investigated conditions.

Extraction of titanium (IV) from real chloride leach liquor of ilmenite was carried out with 0.1 mol·L−1 di-(2-ethylhexyl) phosphoric acid (HDEHP) in kerosene. Equilibrium and kinetics studies for Ti(IV) were carried out in the presence of impurities that were leached with Ti(IV). Parameters affecting extraction rate of Ti(IV) from chloride media in the presence of Fe(III), Mg(II), and Al(III) were studied to evaluate the stoichiometry of extracted Ti(IV) species. It is found that the extraction rate of Ti(IV) is dependent on the extractant concentration and pH of solution. Under the optimum conditions, more than 95 % Ti(IV) can be extracted. On the basis of slope analysis method, the extracted species of Ti(IV) appears to be [TiO(H2A2)2]org, where H2A2 refers to HDEHP. Further, the kinetic studies of the extraction process of Ti(IV) and other metal ion impurities were carried out by a Lewis cell with a constant interfacial area of 16.7 cm2. Analysis of the experimental results suggests that TiO2+ extraction rate by HDEHP is the first with respect to hydrogen ion concentration and HDEHP concentration. The results are interpreted by a reaction mechanism where the extraction process is controlled by a diffusion process at the interface rather than in the bulk phase.

The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5 ± 0.3%, 238.6 ± 7.8 kBq m(-3) and 213 ± 6.9 mBq m(-2) s(-1), respectively. These values were varied and enhanced slightly in the fine grain sizes (F1 0.125 mm) by a factor of 1.05 folds compared to the bulk residue. It was also found that release of radon from residue PG waste was controlled positively by radium (Ra-226), calcium (CaSO4) and strontium (SrO). About 67% of radon release attributed to the grain size below 0.5 mm, while 33% due to the large grain size above 0.5 mm. The emanation fraction of Rn-222 is increased with moisture content and the maximum emanation is ∼43% of moisture of 3-8%. It reduced slowly with the continuous increase in moisture till 20%. Due to PG waste in situ can be enhancing the background to the surround workers and/or public. Therefore, the environmental negative impacts due to release of Rn-222 can be minimized by legislation to restrict its civil uses, or increasing its moisture to ∼10%, or by the particle size separation of the fine fraction containing the high levels of Ra-226 followed by a suitable chemical treatment or disposal; whereas the low release amount can be diluted and used in cement industry, roads or dam construction.

Acid leaching for different types of mixed spent Li-ion mobile batteries is carried out after alkali decomposition using NH4OH followed by H2SO4 + H2O2 leaching. In the alkali decomposition step, the effects of reaction time, NH4OH concentration, liquid/solid mass ratio and reaction temperature on the decomposition process are investigated to remove Al, Cu, Mn, Ni, Co, and Li. After alkaline treatment, the alkali paste is treated to leach the remaining metals using H2SO4 + H2O2. The significant effects of reaction time, acid concentration, H2O2 concentration, liquid/solid mass ratios and reaction temperature on the leaching rate are studied. More than 97% of Al, Mn, Ni, Co, and Li and about 65% Cu are leached in two stages. Kinetic analysis shows that, the data fit with chemical reaction control mechanism and the activation energies for the investigated metals using the Arrhenius equation ranged from 30.1 to 41.4 kJ/mol. Recovered metals are precipitated from the leaching liquor at varying pH values using NaOH solution and Na2CO3. Firstly, Mn is precipitated as MnCO3 at pH = 7.5. Secondly, at pH = 9.0, nickel is precipitated as NiCO3. Thirdly, as the pH of the leaching liquor reaches 11–12, Co(OH)2 is precipitated and the remaining Li is readily precipitated as Li2CO3 using a saturated Na2CO3 solution. Based on the experimental data, a flow sheet is developed and tested for the recovery process.

Extraction and separation of divalent Mn and Zn ions from acidic sulfate solutions containing 0.05 M of each metal ion have been carried out using 0.04 M Na-CYANEX 272 in kerosene. The influences of the following parameters were studied: shaking time, equilibrium pH, extractant concentration, diluents type, and temperature. The extraction percentage of both metal ions increased with increasing equilibrium pH in the range 2.0–4.0 and 2.75–6.0 for Zn(II) and Mn(II), respectively. The separation factor, S(Zn/Mn), increases with the increase in pH to reach a maximum value of about 24 × 103 at pH 4.0. Extraction of both metal ions increased with increasing extractant concentration. Aliphatic diluents were preferred compared to aromatic diluents. The thermodynamic parameters (ΔH, ΔS, and ΔG) for Mn(II) and Zn(II) were calculated. The extraction mechanism of both metals by Na-CYANEX 272, stripping from loaded extractant and recycling of extractant used in the extraction process were also investigated.

A hierarchically porous structure composite (sponge-GO) is prepared by eco-friendly and a simple immersing of a local sponge in a good dispersed GO aqueous media. Where, appropriated weight of the sponge washed several times with distilled-water and ethanol, then immersed in GO suspended solution (3 mg/mL) and left to absorb all GO suspension. The resulted sponge-GO was dried at 70 °C for 72 h. and characterized by SEM, FTIR, Raman, TGA, and EDS. The characterization results indicate that GO sheets perfectly contact with the sponge Skelton network. The fabricated sponge-GO used as a filtration device in a laboratory made continuous filter system. Methylene blue (MB) is used as a chemical contaminant in wastewater to study the adsorption ability of our system. The parameters affecting on the sorption processes as, composite dose, concentration of dye, solution pH, temperature and NaCl dose were studied. The isotherm models, Langmuir, Freundlich and Tempkin, explained that the organic contaminate prefers to adsorbed as a monolayer with high sorption efficiency qe = 19.60 mg g−1. It is evident that this filter material possesses good capability and stability. The experimental studies illustrated that sponge-GO can be reused. The breakthrough curve, Yoon–Nelson model and comparison study were also investigated.

Separation of cobalt from mixed-waste mobile phone batteries containing LiCoO2 cathodic active material was investigated using selective precipitation and chelating resin. Cobalt was recovered from the active powder materials containing 47 % Co oxide together with Mn, Cu, Li, Al, Fe, and Ni oxides. The metal ions were leached sufficiently using 4 M HCl. The metal ions detected spectrophotometrically were removed from the leaching solution by selective precipitation at pH 5.5, with cobalt loss of 27.5 %. Conditions for achieving a recovery of Co in the filtrate by chelating resin were determined experimentally by varying the pH and time of the reaction, as well as the initial resin-to-liquid ratio. The cobalt was efficiently determined by absorption spectrometry at λ max 510 nm. Chelating polyamidoxime resin was synthesized by polymerization of acrylonitrile and followed by amidoximation reaction. Physically cross-linked gel of polyacrylonitrile was made by a cooling technique.

In this work, the adsorption of chemical oxygen demand (COD) and biological oxygen demand (BOD) from treated sewage with low-cost activated carbon prepared from date palm shell waste by chemical activation method was studied. Different parameters affecting the adsorption process such as carbon dose, pH, contact time, agitation rate, and temperature were studied. Adsorption equilibrium was attained after 150 min at pH 6.0 with agitation rate of 400 rpm at 25 °C. The results showed that COD removal percentage of 95.4 and 92.8% for BOD was obtained with carbon dosage of 0.1 g/100 ml of solution. The experimental batch equilibrium results follow linear, Langmuir, and Freundlich isotherm models. The experimental data was fitted to a pseudo-second-order kinetics model controlled by pore diffusion. Thermodynamic parameter values of ΔH 0, ΔG 0, and ΔS 0 were calculated. The obtained data indicated that the adsorption was spontaneous, endothermic nature and reflects an increased randomness and degree of disorderliness at the activated carbon/sewage interface during the adsorption process investigated in this study. Concentrations of different impurities were reduced to very small value by investigated adsorption process.

In this work, the extraction of Pd(II) with triisobutylphosphine sulfide (CYANEX 471X) in kerosene from nitric acid medium has been studied. The effects of different parameters affecting the extraction of the investigated metal ion such as nitric acid, extractant, metal ion concentration and temperature were separately investigated. The stoichiometry of the extracted metal species was found to be Pd(NO 3 ) 2 .CYANEX 471X. The stripping of the extracted metal species was carried out using stabilized thiosulfate solution. The results indicate the possibility of separation of palladium from some interfering ions namely; Co(II), Fe(III), Cu(II), Cd(II) and Zn(II). Extraction of Pd(II) from hydrochloric and sulfuric acid media was also carried out. Thereafter, the method developed was applied for the recovery and separation of Pd and other metal ions from a synthetic solution similar in composition to that expected from the leaching of spent automotive catalyst in hydrochloric acid.

Manganese leaching and recovery from pyrolusite ore, was investigated by using H 2 SO 4 as a leachant and H 2 O 2 as a reducing agent. The effects of agitation, H 2 O 2 concentration, H 2 SO 4 concentration, liquid/solid mass ratio, leaching time and reaction temperature on manganese recovery were studied. The optimal leaching conditions were determined as 4.0 M H 2 SO 4 and 0.8 M H 2 O 2 using liquid–solid mass ratio of 5.0 for 90 min at 40 °C and ore particle size of 44–37 μm. Under these conditions, the leaching efficiency was 92.0% for Mn. It was found that the use of H 2 O 2 as a reducing agent for the reductive leaching of manganese increased the leaching rate. Analysis of the experimental results indicted that the leaching process is fitted by a chemical reaction model in temperature range 20–40 °C, and at higher temperature, 45–70 °C, the diffusion reaction model prevails. Activation energies for these models were calculated to be 49.5 kJ∙mol − 1 and 10.6 kJ∙mol − 1 , respectively. Based on the experimental results, a separation method and flow sheet were developed and tested to separate high purity MnSO 4 .H 2 O (> 99.4%). Comparison between the present results and that reported in the literature are given.

A kinetic study of the leaching of ilmenite paste (resulting from ilmenite treatment by KOH) by sulfuric and oxalic acids has been investigated. The effects of the reaction agitation speed, ilmenite paste particle size, acid concentration, acid/paste mass ratio and temperature on titanium recovery percent from the KOH decomposed ilmenite are reported. The leaching rates are significantly influenced by the reaction temperature and acid concentration. The observed effects of the relevant operating variables on the leaching rates are consistent with a kinetic model for chemical control. The apparent activation energy for the leaching of titanium has been calculated using the Arrhenius expression. The data obtained are compared and discussed with available reported results. Further a flow diagram for production of TiO 2 based on KOH decomposition of ilmenite paste–oxalic acid leaching is given.

A solvent extraction study has been carried out to extract and separate zirconium and hafnium from nitrate medium by using some phosphine oxide extractants (CYANEX 921, CYANEX 923, and CYANEX 925) in kerosene. The influence of the different factors affecting the extraction process was studied in detail. Apparently the rate of extraction of Zr(IV) and Hf(IV) in CYANEX 921, CYANEX 923, and CYANEX 925 is reasonably fast. The extraction increases with increasing temperature, suggesting that the reaction is endothermic. The stripping percent of Zr(IV) and Hf(IV) by 0.5 M HNO3 from the loaded organic phase after two stages reached 97.5% and 10.2%, respectively, which lead to good separation of the two metals. Under the optimum conditions, the extraction of zirconium was about 90, 87.6, and 91.6% and separation factors equal to 17, 21.4, and 40.7 were obtained for CYANEX 921, CYANEX 923, and CYANEX 925, respectively. The results obtained reveal that 2.0 M nitric acid is the optimum acid concentration fo...

Ammonium hydroxide decomposition of ilmenite slag was studied as part of an improved process to obtain high purity titanium oxide. The kinetics of the decomposition reaction was investigated in terms of the slag particle size, NH 4 OH concentration, NH 4 OH/slag mass ratio and reaction temperature. It was found that digestion of the ground ilmenite slag in 4 M NH 4 OH at a temperature of 150 °C decomposed the slag with the formation of ammonium titanate ((NH 4 ) 2 TiO 3 ) which was readily hydrolyzed in hot water to high purity anatase (≥ 99.8% TiO 2 ). Analysis of the decomposition reaction kinetics found that the reaction was chemically controlled with an apparent activation energy of 27.8 ± 1.6 kJ mol − 1 . Based on the experimental results, a flow sheet was developed and tested.

A comparative study of the solvent extraction of vanadium(V) from hydrochloric acid and sodium hydroxide media was separately carried out using Aliquat-336 (methyltrioctylammonium chloride) extractant dissolved in kerosene containing 10% n-octanol as phase modifier. The different parameters affecting the extraction process including acid, alkali, extractant, metal concentrations, phase ratio and loading capacity as well as the temperature were separately investigated. Vanadium(V) species were suggested to be (H 2 V 10 O 28 ) 4 − and (VO 3 OH) 2 − in acidic and alkaline solutions, respectively. Based on the obtained results, the extraction equilibria were deduced and the optimum conditions for the extraction of vanadium were proposed. The method was applied for treatment of the spent catalyst used in the manufacture of sulphuric acid industry giving a recovery of 93.0% for vanadium in the whole process.

The effects of reaction time, KOH concentration, alkali-to-ilmenite mass ratios and reaction temperature on titanium decomposition were investigated. Minor amounts of titanium and iron were leached (less than 2%) from the decomposed ilmenite ore in the alkaline KOH solution. After alkaline treatment, the ilmenite paste was leached to extract iron, titanium, chromium and vanadium by adding sulfuric acid, hydrochloric acid or oxalic acid. The significant effects of reaction time, acid concentration, acid-to-ilmenite mass ratios and reaction temperature on the leaching were studied for each acid. About 93%, 92% and 89% of titanium could be leached from the alkaline treated ilmenite paste, under the optimal conditions by oxalic acid, hydrochloric acid and sulfuric acid, respectively.

Copper/Copper oxide (Cu/Cu2O) nanoparticles were synthesized by modified chemical reduction method in an aqueous medium using hydrazine as reducing agent and copper sulfate pentahydrate as precursor. The Cu/Cu2O nanoparticles were characterized by X-ray Diffraction (XRD), Energy Dispersive X-ray Fluorescence (EDXRF), Scanning Electron Microscope (SEM), and Transmission Electron Microscope (TEM). The analysis revealed the pattern of face-centered cubic (fcc) crystal structure of copper Cu metal and cubic cuprites structure for Cu2O. The SEM result showed monodispersed and agglomerated particles with two micron sizes of about 180 nm and 800 nm, respectively. The TEM result showed few single crystal particles of face-centered cubic structures with average particle size about 11-14 nm. The catalytic activity of Cu/Cu2O nanoparticles for the decomposition of hydrogen peroxide was investigated and compared with manganese oxide MnO2. The results showed that the second-order equation provides the best correlation for the catalytic decomposition of H2O2 on Cu/Cu2O. The catalytic activity of hydrogen peroxide by Cu/Cu2O is less than the catalytic activity of MnO2 due to the presence of copper metal Cu with cuprous oxide Cu2O. © 2015 BCREC UNDIP. All rights reservedReceived: 6th January 2015; Revised: 14th March 2015; Accepted: 15th March 2015How to Cite: Badawy, S.M., El-Khashab, R.A., Nayl, A.A. (2015). Synthesis, Characterization and Catalytic Activity of Cu/Cu2O Nanoparticles Prepared in Aqueous Medium. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (2): 169-174. (doi:10.9767/bcrec.10.2.7984.169-174) Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.2.7984.169-174

Click chemistry has been utilised for the preparation of new tris(triazolyl)triazines containing aliphatic and polar side chains through coupling of 2,4,6-triethynyl-[1,3,5]triazines, which possess free terminal alkyne moieties with substituted aromatic azides. The cytotoxic activity and in vitro anticancer potential of the newly synthesised compounds have been evaluated against seven human cancer cell lines including liver HepG2, breast MCF-7, lung A549, acute myeloid leukemia HL-60, colon HCT116, and prostate PC3 cancer cell lines in addition to human normal melanocyte, HFB4. The results revealed that all the compounds did not exhibit any activity against A549, HL-60, and PC3. However compound G2 was effective against MCF-7 and HepG2 cancer cell lines. On the other hand, compound G1a exhibited higher potency against MCF-7 and HepG2 cells with no toxicity on normal cells in comparison with the standard drug doxorubicin.