Stability and extraction study of phenolic wastewater treatment by supported liquid membrane using tributyl phosphate and sesame oil as liquid membrane

Phenols pose a risk to the environment and to human health. Phenol and its derivatives are toxic pollutants, frequently found in surface and tap waters, and in aqueous effluents from various manufacturing processes. In this paper, an experimental study regarding transport of phenol through a supported liquid membrane (SLM) using tributyl phosphate (TBP) and sesame oil as liquid membrane (LM) was performed. Factors affecting permeation of phenol such as initial phenol concentration, carrier concentration, feed phase pH and stripping phase concentration were analyzed using Taguchi method. Optimal experimental condition of phenol transport was obtained using analysis of variance (ANOVA) after 7 h extraction (feed concentration: 200 mg/L; carrier concentration (%TBP): 40%; feed pH: 2; strip phase concentration: 1.1 M). Mass transfer coefficient for this system was evaluated, and compared with similar works, and it was shown that it has the highest mass transfer rate. In addition to transport study, stability of the membrane was investigated by examination of stripping phase concentration, carrier concentration and salt concentration effects.     

Microwave noncontact examination of disbond and thickness variationin stratified composite media

Numerical and experimental results of a microwave noncontact, nondestructive detection and evaluation of disbonds and thickness variations in stratified composite media are presented. The aperture admittance characteristics of a flange mounted rectangular waveguide radiating into a layered, generally lossy dielectric media backed or unbacked by a conducting sheet is modeled. The theoretical implementation is based on a Fourier transform boundary matching technique to construct the field components in each medium, coupled with a stationary form of the terminating aperture admittance of the waveguide. The model can serve as a reliable test bed for real-time examination of layered composite media. Experimental results for several cases are presented which show good agreement with the theoretical findings. This is a versatile technique for near-field in situ interrogation of stratified composite media which provides for high resolution measurements     

An efficient synthesis of 2,4,6-triarylpyridines catalyzed by heteropolyacid under solvent-free conditions

Preyssler type heteropolyacid is found to be an efficient catalyst for the synthesis of 2,4,6-triarylpyridines in good yields. The catalyst is recycled and reused several times.     

One-step synthesis of tenorite (CuO) nano-particles from Cu4 (SO4) (OH) 6 by direct thermal-decomposition method

In this research work, CuO nano-particles were synthesized at 750 °C (for 2 h) by the direct thermal-decomposition method using the brochantite as precursor. The nano-particles were characterized using X-ray diffraction (XRD), energy dispersive spectra (EDS), infrared spectrum (IR), and scanning electron microscope (SEM). SEM image showed that the CuO nano-particles were of rod shape with diameter and length of 235 ± 5 nm and 856 ± 5 nm, respectively. As a result, this method could be used at an industrial scale as a cheap and convenient way in production of pure tenorite nano-particles.     

Preparation and characterization of SAPO-34 – Matrimid 5218 mixed matrix membranes for CO2/CH4 separation

Different SAPO-34 zeolite loaded Matrimid^® 5218 mixed matrix membranes (MMMs) were prepared by solution casting method and characterized using XRD and SEM analysis. Findings showed that semi crystalline neat polymer becomes more crystalline after thermal treatment at higher temperatures close to Matrimid^® 5218 glass transition temperature. Furthermore, incorporation of crystalline filler particles of SAPO-34 zeolite resulted in more and more crystallinity of the MMMs. SEM images also exhibited acceptable contacts between the filler particles and the polymer chains. Permeation measurement showed that CO₂ permeabilities and CO₂/CH₄ selectivities of the MMM with 20 wt% loading of SAPO-34 zeolite particles up to 6.9 (Barrer) and 67, respectively. This can be attributed to size discrimination of SAPO-34 pores that falls between CO₂ and CH₄ kinetic diameters.     

Fuzzy Multi-Objective Simulation-Optimization of Stepped Spillways Considering Flood Uncertainty

Water Resources Management - The design of stepped spillways is a multi-objective optimization problem in which the uncertainty of parameters plays a key role in the stepped spillways’...     

Utilization of Grid partitioning based Fuzzy inference system approach as a novel method to estimate solubility of hydrocarbons in carbon dioxide

Recently due to increasing demand for energy and declination of oil reservoir the researchers have been encouraged to investigate the enhancement of oil recovery (EOR) approaches. One of popular and wide applicable processes in EOR is carbon dioxide injection which is attractive for researchers and industries due to environmentally aspects, good efficiency in displacement and low cost. The carbon dioxide injection causes the hydrocarbons extracted from crude oil so the solubility of hydrocarbon in carbon dioxide which is one of the critical parameters affects this phenomenon becomes interesting topic for researchers. In the present work Grid partitioning based Fuzzy inference system approach as a new method for prediction of solubility of hydrocarbons in carbon dioxide as function of temperature, pressure and carbon number of alkane was applied. To show the accuracy of the model the coefficients of determination were determined as 0.9902 and 0.9584 for training and testing phases respectively.     

Application of Grid partitioning based Fuzzy inference system and ANFIS as novel approach for modeling of Athabasca bitumen and tetradecane mixture viscosity

The heavy oil and bitumen reservoirs have effective role on supplying energy due to their availability in the world. The bitumen has extremely high viscosity so this type of reservoirs has numerous problems in production and trans- portation.one of the common approach for reduction of viscosity is injection of solvents such as tetradecane. In the present study the Grid partitioning based Fuzzy inference system was coupled with ANFIS to propose a novel algorithm for prediction of bitumen and tetradecane mixture viscosity in terms of pressure, temperature and weight fraction of the tetradecane. In the present study, the coefficients of determination for training and testing phases are determined as 0.9819 and 0.9525 respectively and the models are visualized and compared with experimental data in literature. According to the results the predicting method has acceptable accuracy for prediction of bitumen and tetradecane mixture viscosity.     

Sources and Health Risk of Organic Compounds in Respirable Particles in Tehran,Iran

Forty-one respirable particle (PM₄) samples were collected from October 2011 through March 2012. This timespan covered the fall and winter seasons in Tehran, Iran. The associated polycyclic aromatic hydrocarbon (PAH) and n-alkane concentrations were analyzed to investigate the sources of these compounds and health risks of the former. The average total PAH and n-alkane concentrations were 16.2 ng/m³ and 758 ng/m³, respectively. The most abundant PAHs were 2- and 3-ring compounds, while the most abundant n-alkanes were nC₁₆ and nC₁₈. The results of source identification by factor analysis (FA) are consistent with and complementary to those from diagnostic ratios (DRs). The PAH DRs indicate a dominant contribution from pyrogenic sources, in particular diesel engines from local traffic sources, while FA reveals a diesel-fuelled vehicle emission related factor, a gasoline engine emission-related factor, an industrial source factor and a wood combustion, incineration and tire tread source factor. The n-alkane DRs indicate dominant contributions from anthropogenic sources or vehicular emissions, while FA reveals a fossil fuel combustion factor and a biogenic source factor. Although the average BaP concentration was below the Iran Department of Environment's annual average standard of 1 ng/m³, the BaP-equivalent concentration of the PAHs (BaP_PEQ) indicates harmful effects cannot be ruled out. The ICR_L and ICR_U data suggests a potential cancer risk incidence of about 1–54 individuals per million in the population from a lifetime of 70 years inhalation of particle associated PAHs in Tehran. These findings highlight the importance of reducing emissions from traffic, in particular emissions from diesel-fuelled vehicles, in Tehran.     

Preparation and characterization of poly(vinylidene fluoride)-13X zeolite mixed matrix membranes for lithium ion batteries' separator with enhanced performance

13X zeolite was hydrothermally synthesized and poly(vinylidene fluoride) (PVDF)/13X zeolite particles mixed matrix membranes were prepared using phase inversion method as the lithium-ion battery separator. Hydrophilic and porous 13X zeolite loading impacts on the critical separator properties of morphology, wettability, electrolyte uptake, and high temperatures dimensional stability were investigated using scanning electron microscopy, contact angle, and thermal shrinkage analysis. Electrolyte uptake of the 13X zeolite particles loaded PVDF separators increased and also the incorporation facilitated the lithium ions migration (ion conductivity) due to the Lewis acidity of their structure. The 8 wt% 13X zeolite loaded separator (S2) revealed higher porosity (~+20%), electrolyte uptake (+80%), ion conductivity (+80%), and thermal shrinkage (~−47% at 165°C). C-rate capability and cycle performance of a cell battery assembled using the S2 separator considerably improved compared with those of the assembled by the neat PVDF and commercial polypropylene separators.