Type Of Diluent Research Articles

URANIUM REMOVAL FROM AQUEOUS SOLUTION USING TRI-N-BUTYL PHOSPHATE AND DI-2-ETHYLHEXYL PHOSPHORIC ACID FUNCTIONALIZED POLYESTER SHEET AND CHARCOAL AS ADSORBENTS

The present investigation deals with the removal of uranium from a nitric acid waste solution (Raffinate solution: produce during yellow cake of uranium production) using the extraction chromatography technique (solvent impregnated material) ), where Tri-N-butyl phosphate (TBP) and Di-2-ethylhexyl phosphoric acid (D2EHPA) solvents were impregnated upon polyester sheet and charcoal respectively then the impregnated resin were tested for uranium removal. Thus, the factors affecting the impregnation process namely, solvent concentration, impregnation time, volume/mass ratio, impregnation temperature and diluents type were studied. Secondly the influences of initial uranium concentration, adsorption temperature, contact time, pH on the uranium adsorption on the prepared materials were studied. From the results the isotherm models also calculated to determine uranium adsorption behavior by the prepared TBP and D2EHPA impregnated polyester sheet and charcoal respectively. Both prepared materials were found to be fitted with Langmuir than Freundlich model isotherm.

Component analysis of illicit morphia tablets (clandestine laboratory preparation) using gas chromatography mass spectrometry: a case study

BackgroundVarious synthetic or semi-synthetic drugs like cocaine, amphetamine type stimulants (ATS), and heroin are produced and processed in clandestine laboratories. Every clan lab has its own procedures and protocols for drug synthesis and processing. A drug can be brought up in different forms like pharmaceutical tablets or raw street powder or any else, depending upon different types of adulterants or diluents and the physical modifications required for its transportation. Since a specific drug is synthesized by various clandestine laboratories, it is likely to have some differences between the two samples due to slightly different synthesis protocols used or the nature and concentration of adulterants. Detailed analysis of drug samples can determine, whether the drug belongs to common source or not. The basic purpose of alterations in physical form is to deceive the law enforcement agencies and to increase the bulk.Case presentationIn this article, a clandestine product of an altered form of a drug was analyzed and reported. Two samples of orange colored “morphia tablets” seized by law enforcement officials were submitted for chemical analysis. Both of the samples were analyzed to determine physical and chemical characteristics. In both samples, the tablets were orange in color. The average weight of a tablet was 58.24 mg for sample A, and 68.85 mg for sample B. Qualitative analysis using GC-MS showed that tablets in sample A were composed of caffeine, dextromethorphan, hydromorphone, acetylcodeine, and heroin, while the tablets in sample B were composed of caffeine, acetylcodeine, heroin, papaverine, and noscapine. The concentration of heroin in sample B was much higher than that in sample A.ConclusionThe analysis of morphia tablets showed that these tablets were an altered form of street heroin. On the basis of variation in weight, heroin concentration, impurities, and adulterants in both the samples analyzed, it can be concluded that they belonged to some different sources. Complete drug profiling for organic and inorganic components of tablets is recommended for future prospective.

Effects of a special diluent as an agent of improving the crystallizability of poly(L-lactic acid)

It has been found that a special type of diluent can act as an agent to improve the crystallizability of poly(L-lactide) (PLLA). To present clear experimental results to support such an ability, we used time-resolved small and wide-angle X-ray scattering (SWAXS) to follow the isothermal crystallization of PLLA. The WAXS results show the enhancing effects of the diluent on the crystallization of PLLA, such as the reduction of the induction period and the acceleration of crystallization. Furthermore, the transformation from the δ phase to the α phase was also detected in the presence of the diluent. The growth of the crystalline lamellae in their thickness direction was accelerated in the presence of the diluent. It was further found that the diluent can accelerate the space filling of the stacks of crystalline lamellae in the specimen. The clear experimental results are revealed to confirm that a special type of a diluent can act as an agent of improving the crystallizability of poly(L-lactide) (PLLA). We conducted time-resolved SWAXS to follow the isothermal crystallization of PLLA. The WAXS result shows enhancing effects of the diluent on the crystallization of PLLA such as reducing induction period and accelerating crystallization. The growth of the crystalline lamellae in their thickness direction and the space filling by the stacks of crystalline lamellae are found to be accelerated in the presence of the diluent.

Comparison of multi-linear regression, particle swarm optimization artificial neural networks and genetic programming in the development of mini-tablets

In the present study, the preparation of pharmaceutical mini-tablets was attempted in the framework of Quality by Design (QbD) context, by comparing traditionally used multi-linear regression (MLR), with artificially-intelligence based regression techniques (such as standard artificial neural networks (ANNs), particle swarm optimization (PSO) ANNs and genetic programming (GP)) during Design of Experiment (DoE) implementation. Specifically, the effect of diluent type and particle size fraction for three commonly used direct compression diluents (lactose, pregelatinized starch and dibasic calcium phosphate dihydrate, DCPD) blended with either hydrophilic or hydrophobic flowing aids was evaluated in terms of: a) powder blend properties (such as bulk (Y1) and tapped (Y2) density, Carr’s compressibility index (Y3, CCI), Kawakita’s compaction fitting parameters a (Y4) and 1/b (Y5)), and b) mini-tablet’s properties (such as relative density (Y6), average weight (Y7) and weight variation (Y8)). Results showed better flowing properties for pregelatinized starch and improved packing properties for lactose and DPCD. MLR analysis showed high goodness of fit for the Y1, Y2, Y4, Y6 and Y8 with RMSE values of Y1 = 0.028, Y2 = 0.032, Y4 = 0.019, Y6 = 0.015 and Y8 = 0.130; while for rest responses, high correlation was observed from both standard ANNs and GP. PSO-ANNs fitting was the only regression technique that was able to adequately fit all responses simultaneously (RMSE values of Y1 = 0.026, Y2 = 0.022, Y3 = 0.025, Y4 = 0.010, Y5 = 0.063, Y6 = 0.013, Y7 = 0.064 and Y8 = 0.104).

Membrane-assisted enrichment of zinc(II) from and into ammoniacal media through non-dispersive synergistic extraction

Abstract The enrichment of zinc(II) in ammoniacal media with non-dispersive synergistic extraction (NDSX) was achieved in a sandwich-supported liquid membrane module, in which a mixed extractant containing 4-ethyl-1-phenyl-1,3-octadione (HA) and trioctylphosphine oxide (TOPO) was used as the carrier. Several parameters of Zn(II) transport, including carrier concentration, diluent type, feed pH, total ammonia concentration, and temperature, were systematically investigated. The results showed that the mixing of TOPO with HA can effectively improve the Zn(II) enrichment from and into ammoniacal solutions. The transport efficiency of zinc increases with increasing carrier concentration and temperature. Moreover, Zn(II) transport is dependent on the total ammonia concentration and solution pH of the feed phase. The nonpolar n-octane is more beneficial to zinc transport than the polar octanol. Five successive transports exhibit excellent membrane stability and the effective uphill transport of zinc from and into ammoniacal media with NDSX.

Extraction of 1-amino-2-Naphthol-4-Sulfonic acid from wastewater using trioctylamine (N, N-dioctyloctan-1-amine) in methyl isobutyl ketone

Wastewater containing 1-amino-2-naphthol-4-sulfonic acid (ANS) is mainly derived from the dye production process, causing serious environmental problems. In this work, extraction of ANS from wastewater was carried out using trioctylamine (TOA) under condition of methyl isobutyl ketone (MIBK) as a diluent. The effects of diluent type, concentration of TOA, temperature and pH on the distribution coefficient (D) were discussed in detail. The results showed that the value of D = 76 was obtained with TOA (1.41 mol kg−1) + MIBK at 25 °C and pH = 1.1. After that, the extraction mechanism was determined by analyzing the chemical bonds of the complex compound using UV–vis, FT-IR and 1H NMR. The experimental results showed that the extractant could be regenerated by back extraction. Specially the distillation process was simulated using Aspen Plus and the results verified its feasibility in the process of extractant regeneration. The proposed extraction system is conductive to both environment and technology.

Effects of epoxy, hardener, and diluent types on the hardened state properties of epoxy mortars

Three epoxy resins and three types of glycidylether-based reactive diluents were used together in epoxy mortars. Six different amine-based hardeners, four aliphatic and two cycloaliphatic, were used in the mixtures. Test results showed that a hardener with higher functionality results in mortars with higher strength. The combination of diluent and hardener was found to affect both the compressive and flexural strengths of the mortars. The adhesion strengths of the mortars (to a sand-blasted concrete surface) were obtained by pull-off test. It was found that lactic and acetic acids have different levels of destruction in the epoxy mortars.

A Simple and Inexpensive Image Analysis Technique to Study the Effect of Disintegrants Concentration and Diluents Type on Disintegration

Tablets disintegration is often the result of a size expansion of the tablets. In this study, we quantified the extent and direction of size expansion of tablets during disintegration, using readily available techniques, that is, a digital camera and public domain image analysis software. After validating the method, the influence of disintegrants concentration and diluents type on kinetics and mechanisms of disintegration were studied. Tablets containing diluent, disintegrant (sodium starch glycolate, crospovidone, or croscarmellose sodium), and lubricant were prepared by direct compression. Projected area and aspect ratio of the tablets were monitored using image analysis techniques. The developed method could describe the kinetics and mechanisms of disintegration qualitatively and quantitatively. Sodium starch glycolate and crospovidone acted purely by swelling and shape recovery mechanisms. Instead, croscarmellose sodium worked by a combination of both mechanisms, the extent of which changed depending on its concentration and the diluent type. We anticipate that the method described here could provide a framework for the routine screening of tablets disintegration using readily available equipment.

Development of stable green emulsion liquid membrane process via liquid–liquid extraction to treat real chromium from rinse electroplating wastewater

This research addresses the development of stable green ELM process for chromium removal from industrial effluents where CrO42− and Cr2O72− is the predominant species. Types of carriers, diluents and stripping agents undergo screening via LLE process. Meanwhile, the parameters studied for ELM stability and extraction were surfactant and modifier concentrations, homogenizer speed and emulsifying time. The formulate condition of stable ELM process was 0.04M TOMAC in palm oil, 0.05M NaOH, 3% (w/v) Span 80, 5% (w/v) octanol, 10,000rpm homogenizer speed and 3min emulsifying time. At this condition, 97% of chromium was extracted with breakage rate of 10%.

Mitigation effects on the explosion safety characteristic data of ethanol/air mixtures in closed vessel

Abstract This paper presents new results of an experimental study on the explosion characteristics: the explosion pressure, the rate of pressure rise (or the deflagration index), the explosion delay time and the laminar burning velocity for ethanol/air mixtures with ethanol concentrations between 3.5 vol% and 20.0 vol% in the presence of various diluents (nitrogen, exhaust gas, water and carbon dioxide with dilution concentrations from 0 vol% to 20 vol%), at various initial pressures from 0.25 bar to 1.0 bar and at an initial temperature of 373 K. The influence of the diluent type and amount on the explosion characteristics is examined together with the influence of the initial pressure. The effectiveness of the diluent gases examined varies from least effective to most effective in the following order: N2, exhaust gas, H2O, CO2. The reported data in this paper (the explosion characteristics and the laminar burning velocity) of ethanol-air mixtures in the presence of various diluents are important safety parameters, useful for design of active protection devices and for safety recommendations.

Ostrich specific semen diluent and sperm motility characteristics during in vitro storage

The dilution of semen is a very important initial process for semen processing and evaluation, storage and preservation in vitro and efficient artificial insemination. The aim of the study was to evaluate the effect of two synthetic diluents (OS1 and OS2) on ostrich sperm motility parameters during in vitro storage. Formulation of OS1 was based on macro minerals (Na, K, P, Ca, Mg) and OS2 on the further addition of micro minerals (Se and Zn), based on mineral concentration determined in the ostrich seminal plasma (SP). Sperm motility was evaluated at different processing stages (neat, after dilution, during storage and after storage) by measuring several sperm motility variables using the Sperm Class Analyzer® (SCA). Processing (dilution, cooling and storage) of semen for in vitro storage purposes decreased the values for all sperm motility variables measured. The percentage motile (MOT) and progressive motile (PMOT) sperm decreased 20% to 30% during 24 h of storage, independent of diluent type. Quality of sperm swim (LIN, STR and WOB), however, was sustained during the longer storage periods (48 h) with the OS2 diluent modified with Se and Zn additions. Quality of sperm swim with use of OS1 was 6% to 8% less for the LIN, STR, and WOB variables. Male fitted as a fixed effect accounted for >60% of the variation for certain sperm motility variables (PMOT, MOT, VCL, VSL, VAP and ALH) evaluated at different processing stages. Semen from specific males had sustained sperm motility characteristics to a greater extent than that of other males during the 24-h storage period.

Structure characterization of UV-curing PEG-b-PPG-b-PEG dimethacrylate cross-linked network

The molecular structure of a series of newly developed ultraviolet (UV) curable electrical contact stabilization materials, which contain polyethylene glycol (PEG)-block-polypropylene glycol (PPG)-block-polyethylene glycol (PEG) capped with methacrylate functional groups on both ends as the reactive oligomers and a methacrylated PEG as the reactive diluent was studied in detail. The effects of reactive diluents, including functionalities and compositions were investigated via a combination of dynamic mechanical analysis, differential scanning calorimetry, FT-IR spectroscopy and wide angle X-ray diffraction. All the films exhibit completely amorphous state at room temperature regardless of the composition or thermal history. However, a small amount of PPPDI molecular chains undergo crystallization upon slow cooling. This crystallization is completely inhibited when mixed with di-functional reactive diluents, owing to the high cross-link density. The introduction of mono-functional reactive diluents restricts but not completely prevents the crystallization process, which causes the resulting films to be difficult to crystallize to lower crystallinity levels. On the other hand, adding non-reactive diluents transforms the resulting films to become a fast-crystallizing material, as a result of the low cross-link density and a large portion of unreacted oligomers along with the unreactive component. Additionally, the degree of heterogeneity for the cross-linked networks is generally increased by the addition of reactive diluents. The molecular structures of PEG-b-PPG-b-PEG dimethacrylate cross-linked networks as well as mixed with different types of reactive diluents at both room temperature and crystallizing temperature were proposed.

Preparation and properties of heat and ultraviolet‐induced bonding and debonding epoxy/epoxy acrylate adhesives

ABSTRACTHeat and ultraviolet (UV)‐induced bonding and debonding (BDB) adhesives were designed and prepared through blending an epoxy resin, diglycidyl ether of bisphenol A (DGEBA) with an epoxy acrylate resin, bisphenol‐A epoxy acrylate resin (BEA). The variation of the chemical structure of DGEBA and BEA in the sequential heat‐ and UV‐curing processes was characterized by Fourier transform infrared spectroscopy (FTIR). The FTIR results indicate that DGEBA and BEA successfully took part in both the heat‐curing and UV‐curing processes. The effects of the mass ratio of BEA to DGEBA, amount of heat‐curing agent, type of diluents, and UV irradiation time on the BDB properties of BDB adhesive were systematically investigated. The results show that the bonding strength increases with the decrease of the mass ratio of BEA to DGEBA and with the increase of the amount of heat‐curing agent in a certain range. The debonding strength decreases with the increase of the mass ratio of BEA to DGEBA. The mass ratio of BEA to DGEBA was set at 10 to ensure the ratio of the bonding strength to debonding strength greater than 10 times. The debonding strength of BDB adhesives also depends on the UV irradiation time, decreasing with the increase of UV irradiation time in a certain range. Based on the FTIR results and the dependence of the bonding and deboning strengths on the reaction conditions, a possible BDB mechanism of BDB adhesive was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46435.

Effect of the diluent on the solvent extraction of neodymium(III) by bis(2-ethylhexyl)phosphoric acid (D2EHPA)

The effect of different types of diluents on the extraction of neodymium(III) from a chloride aqueous feed solution by the acidic extractant bis(2-ethylhexylphosphoric) acid (D2EHPA) was investigated. A total of 11 aliphatic, mixed aliphatic-aromatic and aromatic diluents were considered. D2EHPA was very well miscible with all diluents, even at 90% (v/v) of extractant. Aliphatic diluents gave the highest extraction efficiencies, while aromatic diluents did suppress the formation of emulsions or gels. Although a good separation of Dy(III) over Nd(III) was observed at 0.5 mol/L D2EHPA in all diluents, aromatic diluents were found to yield the highest separation factors. This study shows that the effect of the diluent on the extraction behaviour of Nd(III) is primarily determined by the aliphatic/aromatic content of the diluent. Diluents with the same concentration of aromatics show very similar behaviour. The choice of a diluent can be based on factors other than the extraction behaviour, for instance price and volatility.

Selective copper extraction from sulfate media with N,N-dihexyl-N′-hydroxypyridine-carboximidamides as extractants

Abstract Solvent extraction studies of copper(II) from sulfate media have been carried out using a selected non-commercial extractant N,N-dihexyl-N′-hydroxypyridine-2-carboximidamide (DH2PIA) diluted with toluene and heptane. The presented results indicated that the extraction of copper(II) was very sensitive to the pHeq, extractant concentration and the type of diluent. Also the pH0.5 values depended on the type of diluent and varied from 2 for heptane to 2.8 for toluene. The isotherms of the extraction and the McCabe-Thiele diagram revealed that using the single stage extraction at O/A = 2 Cu(II) can be removed almost completely from the leach solution. Stripping of the loaded copper(II) to the sulfuric acid solution (10%, A/O = 10) yielded rich electrolyte with 37.7 g/L Cu(II), while the stripping test with the spent electrolyte allowed for enrichment of the solution to 67.6 g/L Cu(II). Moreover, the extraction of Cu(II) with DH2PIA from a leach solution containing also Fe(II) is selective and allows to enrich the organic phase in Cu(II).

Separation of Protocatechuic Acid Using Di-(2-ethylhexyl)phosphoric Acid in Isobutyl Acetate, Toluene, and Petroleum Ether

Protocatechuic acid has potential pharmacological significance, like antioxidant, antibacterial, and anticancer activity. The extraction of carboxylic acids from dilute aqueous phase is a topic of current interest to researchers. The present equilibrium study deals with the reactive extraction of protocatechuic acid from an aqueous solution by using di-(2-ethylhexyl)phosphoric acid (D2EHPA) in diluents, such as isobutyl acetate (IBA), toluene, and petroleum ether at isothermal conditions (298 ± 1 K). The physical extraction of protocatechuic acid with pure diluents is also carried out. The difference between the physical extraction and the reactive extraction was studied. The effects of acid concentration (0.001–0.01 mol·kg–1), extractant concentration (0.3445–3.1010 mol·kg–1), and type of diluent on the recovery of protocatechuic acid from aqueous solution were determined. KD values were obtained in the ranges of 1.14–4.03, 0.12–0.67, and 0.08–0.48 for D2EHPA in isobutyl acetate, toluene, and petroleum e...

Solvent extraction of thorium (IV) from chloride solution using Schiff base and its application for spectrophotometric determination

Thorium (IV) was separated from chloride medium by solvent extraction with Schiff base chelating agent, (E)-4-(2-hydroxyphenyl imino) pentane-2-one (AcPh) that was prepared and characterized by FT-IR, 1H NMR, and elemental analysis. The extraction step was studied with regard to experimental parameters such as diluent type, pH, AcPh concentration, A:O ratio, contact time, temperature and interference of diverse ions on the recovery of thorium ion. The thorium (IV) was then back-extracted into aqueous media containing 0.5 M HNO3 to study the stripping conditions that were A:O ratio, contact time and room temperature. The optimum parameters were applied in the studied sample solution for the spectrophotometric determination at 540 nm with Thoron I. The accuracy of the developed method was tested with B2 standard reference material. Furthermore, the proposed method was successfully applied for the spectrophotometric determination of thorium ions in the geologic sample with good accuracy and precision.

The stability of ceftriaxone sodium in vials using different diluents

Ceftriaxone sodium is an important antibiotic used for intravenous or intramuscular administration. The aim of this study was to evaluate the stability of ceftriaxone sodium in vials that dissolved in different types of diluents when stored in different degrees of temperature and different concentrations. Six diluents were used, lidocaine 1%, lidocaine 2%, dextrose 5%, Nacl 0.9%, mixture serum, sterile water used for injection. The solutions of ceftriaxone sodium in sterile water and dextrose 5% (100mg/ml)showed the most stability for 3 days when stored at 25°C, and for 10 dayswhen stored at 4°C, whereas solutions in lidocaine 2% showed the lowest stability for 8 hours at 25°C, and 8days at 4°C. The concentration of the resulted solution has an important effect on the stability such as, the stability of ceftriaxone sodium in lidocaine 1%with concentration (100mg/ml) showed stability for 9 days when stored at 4°C, whereas for 3 days with concentration (250mg/ml).

Removal of Lead from Water by Liquid-Liquid Extraction using trihexyltetradecylphosphonium Chloride in Different Diluents

The feasibility of ionic liquid trihexyltetradecylphosphonium chloride [THTDP][Cl] as extractant in different diluents for the removal of lead (Pb) from water was investigated using laboratory scale liquid-liquid extraction. The tests were conducted using an extraction mixture which consisted of 5% (v/v) [THTDP][Cl] in different diluents, namely toluene and corn oil. In general, the extraction followed anion exchange mechanism and equilibrium extraction can be achieved at extraction time of 5-10 minutes. In addition, the extraction efficiency was found to decrease when the HCl concentration in Pb solution was increased from 1 M to 3 M for both types of diluents, as a result of competition between excessive Cl- and PbCl42- to form complex with [THTDP] cation. The extraction ability of Pb for [THTDP][Cl] was highly dependent on the types of diluents used where corn oil based extraction mixture showed lower extraction efficiency in comparison to toluene based extraction mixture, as a result of its higher viscosity.

Selective Separation of Light and Heavy Rare Earth Elements from the Pregnant Leach Solution of Apatite Ore with D2EHPA

Different separation techniques such as solvent extraction, ion exchange, and precipitation are often used for recovery of rare earth elements (REEs) from pregnant leach solutions obtained from acid leaching. Solvent extraction is generally accepted as the most appropriate commercial technology for separating REEs due to the need to be able to handle larger volumes of diluted pregnant solutions. This study focused on the development of selective separation of light and heavy REEs from the pregnant leach solution obtained from leaching of apatite ore in 1 M sulfuric acid (H2SO4) using solvent extraction. Three different commercial organophosphorus extractants (di-(2-ethylhexyl) phosphoric acid (D2EHPA), 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A) and tributyl phosphate (TBP)), and the influences of experimental parameters such as extractant concentration, organic/aqueous phase ratio, diluent type, pH, extraction time and stripping agent concentration were examined. Results showed that light REEs (LREEs) and heavy REEs (HREEs) in the pregnant leach solution were selectively separated with D2EHPA via a two-stage extraction process. In the first-stage of solvent extraction, >90% of (0.05 g/L) HREEs was extracted with 1.8 M D2EHPA in kerosene while the vast majority (>95%) of LREEs was remained in raffinate. In the second-stage, >93% (1.01 g/L) of LREEs was extracted from the raffinate with 1.8 M D2EHPA dissolved in kerosene at pH 1.6. HREEs (>95%) and LREEs (>90%) loaded with D2EHPA after the first and second-stage of extraction were stripped by 4 M H2SO4 and 1 M H2SO4 solutions, respectively. Distribution of middle rare earth elements (MREEs) was discussed through the extraction processes in this study.