Carbon Tetrachloride In Water Research Articles

Beneficiation of Solutes from Solvents: A Case of Oxalic Acid, Succinic Acid and Ethylenediaminetetraacetic Acid in Carbon Tetrachloride

Background: This paper reports the beneficiation of Oxalic acid, Succinic acid and Ethylenediaminetetraacetic acid solutes from Carbon tetrachloride, Diethyl ether and n-Hexane solvents respectively. These solutes are the extracts obtained from the recovery from the binary immiscible solvents namely: Carbon tetrachloride-Water, Diethyl ether-Water and n-Hexane-Water that were used in accordance with the partition coefficient technique as reported by Onyeocha et. al. This technique was employed in the leaching of the specific solute from the contaminants. As described by Onyeocha et. al., the process was brought about by the diffusion equilibrium attained by the solute in the system i.e. the binary immiscible solvent(s) at a constant temperature and pressure. The spontaneous diffusion is the effect of the partition coefficient developed due to the different degrees of solubilities of the solute in the binary immiscible solvent. The partition coefficient technique is used for extraction, purification and concentration of solutes. Beneficiation is considered as the final process that brings the product (solute) to its most viable state.

Health Indicators: A Review by Thermodynamic Assessment of Acetic Acid in The Presence of Selected Binary Immiscible Solvents

Background: This report reviews the thermodynamic assessment of Acetic Acid in binary immiscible solvents as an insidious health indicator that requires the confirmation of amount present and its treatment prior to discharge in effluents and sewage waste management. This measure upholds sustainability for the clean and green environment. Acetic acid is a potent harmful chemical compound. However, it is used in the chemical industry, medicine, household, and foods. Exposure to industrial compounds that contain Acetic acid is hazardous to health. Severe allergic reactions manifest from exposure to Acetic acid include rash, hives, difficulty in breathing, tightness in the chest, swelling of the mouth, face, lips or tongue, irritation, sensitivity, etc. The use of binary immiscible solvents in the analysis of Acetic acid gives the thermodynamic predictive parameter, namely: Partition coefficient (kD), which serves as an indicator that provides the amount of Acetic acid in the environment under suspect. Also, partition coefficient, kD highlights the efficiency of either the removal of Acetic acid from the environment or gives amount of Acetic acid extracted from effluents/sewage assessment by using the technique on the value(s) obtained from partition coefficients. Methods: Acetic acid was dissolved in three binary immiscible solvents, namely: Carbon Tetrachloride-Water, Diethyl Ether-Water and n-Hexane-Water, at 30℃ and an atmospheric pressure. Varying quantities of Acetic acid (the solute) were distributed into the respective binary immiscible solvents. The different volumes of AnalaR Grade reagent of Acetic acid were respectively poured into the separating funnel. The separating funnel was shaken vigorously and allowed to stand in order to establish equilibrium of diffusion of the solute in the system, as reported earlier by Onyeocha et. al. Titre-values were obtained for the concentrations of Acetic acid in the two phases of binary immiscible solutions that were formed. Results: The results in the three systems were analysed, Acetic acid had the partition coefficient, kD = 0.05838 in Diethyl Ether-Water, the dimerization constant, K = 0.0068 while ionization constant, = 0.03998 in the same system. Acetic acid had the kD = 0.05674, K = 2.0281 in magnitude and = 0.0013, in n-Hexane-Water and kD = 0.01643, K = 250.9771 and = 0.0196 in Carbon Tetrachloride-Water. Conclusion: This work shows that Carbon Tetrachloride-Water, Diethyl Ether-Water and n-Hexane-Water are efficient binary immiscible solvents for the analysis of Acetic acid proven waste treatment management for effluent and sewage disposal to ensure the sustainable clean and green environment devoid of any residual Acetic acid. Indeed, partition function, kD is a novel thermodynamic parameter recently introduced by Onyeocha et. al. for the quantitative evaluation and residual assessment of Acetic acid in the environment.

Toward rapid reduction of carbon tetrachloride in water by zero-valent aluminum/persulfate system.

The oxidation performance of the zero-valent aluminum (ZVAl)/persulfate (PS) combined system had been studied by researchers in the past, which relied on the activation of PS by ZVAl to generate potent oxidizing radicals (•OH and SO4•-) to degrade pollutants. However, ZVAl is a strong reductant and its reduction effect cannot be ignored. The reductive performance of the ZVAl/PS combined system is still unknown. Therefore, carbon tetrachloride (CT), an antioxidant organic pollutant, was selected as the target pollutant to test the reductive performance of the ZVAl/PS system in this study. We found a significant synergistic effect between ZVAl and PS, and the ZVAl/PS combined system could rapidly degrade CT in a wide pH range of 3-11 after an induction period. By SEM-EDS, TEM, XPS, and XRD analysis, it was found that PS could promote the corrosion of the oxide film on the ZVAl surface. The quenching experiment proved that PS could accept the electrons released from ZVAl to produce superoxide radical anion (O2•-), which led to the degradation of CT rather than the oxidative process by •OH and SO4•-. The hydrogen evolution experiment indicated that electronic reduction might play a secondary role in CT degradation. In conclusion, our study further explored the reductive performance of the ZVAl/PS combined system and expanded the pathway of CT degradation without any organic solvent addition, which provides a new strategy for the efficient degradation of refractory halogenated organic pollutants.

Comparisons of the effects of solute interactions on partition coefficient, k D, in selected binary immiscible solvents: a case of oxalic acid and succinic acid.

Background: The molecular distributions of solutes in binary immiscible solvents as used in partition coefficient technique serve as measures of the solute separation, concentration and beneficiation from contaminants. Methods: The effects of solute interactions on partition coefficient, k D, in selected binary immiscible solvents were investigated at 30 0C and atmospheric pressure. The activities from the interactions with changes of concentrations within the solvents were analysed. These were done using simple titration method. The solutes were distributed in the binary solvents and the concentrations from the two layers formed were determined by titration method. The interactions of oxalic acid and succinic acid in carbon tetrachloride-water, diethyl ether-water, and n-hexane-water were studied for the partition coefficient values in the respective systems, to determine the nature and degree of the interfering reactions that are affecting the distributions, and to ascertain the best binary solvents from the three systems. Results: Oxalic acid has the partition coefficient of 0.0738 in carbon tetrachloride-water with the dimerization constant of -15.7092 and ionization constant of 0.0303. Oxalic acid has the distribution coefficient of 0.0173, dimerization constant of 144.0167 and the ionization constant of 0.0035 in diethyl ether-water. Oxalic acid has the partition coefficient of 0.0279, dimerization constant of 20.2798 and ionization constant of 0.0019 in n-hexane-water. Succinic acid has the partition coefficient of -0.05617, dimerization constant of -18.5655 and ionization constant of 0.0284 in carbon tetrachloride-water. In diethyl ether-water, succinic acid has the partition coefficient of 0.0427, dimerization constant of -18.1611 and ionization constant of 0.0332. In n-hexane-water, succinic acid has the partition coefficient of -0.04274, dimerization constant of 71.9491 and ionization constant of 0.0265. Conclusion: From these results, carbon tetrachloride-water is recommended for the purification and extraction of oxalic acid from contaminants. Carbon tetrachloride-water is also the best binary immiscible solvent for succinic acid.

Highly sensitive tetra-slotted gold-coated spiral plasmonic biosensor with a large detection range

An extremely highly sensitive photonic crystal fiber (PCF) based SPR or surface plasmon resonance biosensor is manifested in this article, in a cumulated form of circularly slotted spiral lattice structure (SLS). The numerical performance analysis of the sensor is critically interpreted using the finite element method (FEM), including a perfectly matched layer (PML) and scattering boundary conditions. Very well known chemically stable material gold is used as the plasmonic material and implanted inside the circular slots to lessen the fabrication challenge and oxidation problem. The prospective model shows the maximum value of sensitivity is 41,000 nm/RIU, employing the method of wavelength interrogation and a maximum value of sensitivity of 4242 RIU−1, using the method of amplitude interrogation. The proposed sensor has the capability of detecting analytes in a massive range of the refractive index 1.32 to 1.50 RIU (for wavelength 0.5 µm to 1.55 µm) with a highest sensor resolution of 2.44 × 10−6 RIU. It is highly capable of identifying biomolecules like benzene, carbon tetrachloride, ethyl alcohol, acetone, water, silicon oil, and glucose solution in water, fused silica, cornea, lens, liver cell, and intestinal mucosa of human, polylactic acid, vegetable oil, and glycerol, etc. The sensor exhibits high linearity by showing R2 value 0.97 with a maximum FOM of 683 RIU−1. For large detection range, immense sensitivity, high FOM, and low fabrication complexity, the illustrated sensor can be a supreme candidate in the realm of SPR biosensor.

Preparation of superhydrophobic/superoleophilic copper coated titanium mesh with excellent ice-phobic and water-oil separation performance

The development of advanced materials with superwettability has captured much research interest, because of the increasing environmental concerns and technological requirements. In this work, a titanium mesh coated with copper micro/nanostructures was fabricated via chemical immersion and annealing treatment. The resulting mesh surface consists of titanium and copper oxides with special dendritic and island-like micro-nano binary structures and exhibited remarkable superhydrophobic/superoleophilic property. The superhydrophobic/superoleophilic Ti mesh (SSTM) proved to be efficient for the separation of various water-oil mixtures and exhibited an excellent reusability in repeating separation cycles of water-carbon tetrachloride. Moreover, the SSTM sample displayed great icephobic property including ice-over delay and low ice adhesion. The self-cleaning properties of the SSTM sample were demonstrated using simulated chalk powder that can be easily washed off by injecting water droplets. It also exhibited superior stability in air atmosphere or water over months and great durability under a continuous tap-water flow impacting or abrasion test.

Facile fabricate a bioinspired Janus membrane with heterogeneous wettability for unidirectional water transfer and controllable oil–water separation

A novel smart Janus membrane for unidirectional water transfer and oil–water separation is facilely fabricated by coating graphene nanoplatelets (GNs) onto one side of polyethylene terephthalate (PET) fabric through high-temperature and high-pressure method and subsequently grafting phosphoric acid (HP) into the other side of PET fabric. Results suggest that the prepared HP–PET–GNs Janus membrane with heterogeneous surface wettability attributed to the hierarchical structure of membrane shows special unidirectional water transfer property. The water droplet can penetrate across the membrane from the GNs-coated (hydrophobic) side to the HP-grafted (hydrophilic) side, and be blocked to pass through the membrane from hydrophilic side to hydrophobic side. Moreover, the HP–PET–GNs Janus membrane is found to have the maximum water flux and separation efficiency of 2073 ± 207 Lm−2h−1 and 99.5 ± 0.2% for methylbenzene–water mixture, and the maximum oil flux and separation efficiency of 3113 ± 52 Lm−2h−1 and 99.6 ± 0.1% for carbon tetrachloride–water mixture, respectively. The water separation efficiency and oil separation efficiency could arrive at 99.0 ± 0.1 and 99.3 ± 0.2% even after 10 separation cycles, respectively. It is revealed that the obtained Janus membrane has excellent separation capability for separating the layered oil–water mixtures and possesses wonderful recyclability.

Rapid removal of chloroform, carbon tetrachloride and trichloroethylene in water by aluminum–iron alloy particles

ABSTRACTWater contamination with chlorinated hydrocarbons such as chloroform (CHCl3), carbon tetrachloride (CCl4) and trichloroethylene (TCE) is one of the major public health concerns. In this study, we explored the use of aluminum–iron alloys particles in millimeter scale for rapid removal of CHCl3, CCl4 and TCE from water. Three types of Al–Fe alloy particles containing 10, 20 and 58 wt% of Fe (termed as Al–Fe10, Al–Fe20 and Al–Fe58) were prepared and characterized by electrochemical polarization, X-ray diffraction and energy dispersive spectrometer. For concentrations of 30–180 μg/L CHCl3, CCl4 and TCE, a removal efficiency of 45–64% was achieved in a hydraulic contact time of less than 3 min through a column packed with 0.8–2 mm diameter of Al–Fe alloy particles. The concentration of Al and Fe ions released into water was less than 0.15 and 0.05 mg/L, respectively. Alloying Al with Fe enhances reactivity towards chlorinated hydrocarbons' degradation and the enhancement is likely the consequence of galvanic effects between different phases (Al, Fe and intermetallic Al–Fe compounds such as Al13Fe4, Fe3Al and FeAl2) and catalytic role of these intermetallic Al–Fe compounds. The results demonstrate that the use of Al–Fe alloy particles offers a viable and green option for chlorinated hydrocarbons' removal in water treatment.

Molecular Insights in the Structure and Layered Assembly of Polyelectrolytes at the Oil/Water Interface

Macromolecular assembly at the interface between water and a hydrophobic surface underlies some of the most important biological and environmental processes on the planet. Important model systems for understanding this assembly at such interfaces are polyelectrolytes that have hydrophilic units interspersed along a hydrophobic polymer backbone, similar to many biological macromolecules. This feature article provides recent advances in the molecular factors that contribute to the adsorption and assembly of carboxylic acid-containing polyelectrolytes at the carbon tetrachloride–water interface, a model system for an oil–water interface. Using vibrational sum frequency spectroscopy and interfacial tension techniques, these unique set of studies presented herein identify the factors that dictate whether or not polyelectrolytes will adsorb to the oil–water interface and also describe the specifics of the adsorption process that depend upon factors such as polymer size, charge density, hydrophobicity, conformat...

UTILITY OF HADKAR FACTOR IN THE DETERMINATION OF CRITICAL MICELLE CONCENTRATION OF SURFACTANTS

The drop weight method was used to determine the interfacial tension between organic liquid and solutions of different concentrations of the surfactant, sodium lauryl sulphate (SLS), using Hadkar factor. Two experiments were performed to determine the interfacial tension. In the first experiment the drop weight method was used to determine the interfacial tension between water or aqueous surfactant solutions and benzene (liquid lighter than water) using Hadkar factor H1. In the second experiment the drop weight method was used to determine the interfacial tension between water or surfactant solutions and carbon tetrachloride (liquid heavier than water) using Hadkar factor H2. The plot of interfacial tension between benzene or CCl4 and SLS solutions versus concentration of surfactant solution was used to determine the critical micelle concentration (CMC) of the surfactant. The results were in good agreement with the reported values of CMC for SLS showing the utility of Hadkar factor in the determination of CMC of surfactants.

Metal Ion Induced Adsorption and Ordering of Charged Macromolecules at the Aqueous/Hydrophobic Liquid Interface

Whether a charged macromolecule remains solvated or adsorbs to the interface between two immiscible fluids depends on a variety of complex factors. Ions, in particular, have the capacity to affect the degree of polyelectrolyte hydrophobicity and conformation through electrostatic screening and site-specific interactions. Here, surface-specific vibrational spectroscopy is utilized to probe the roles of ions in the oil–water interfacial behavior of a model carboxylic acid-containing macromolecule. Specifically, the adsorption time dependence, conformation, and extent of carboxylate–cation interactions of poly(methacrylic acid) at the carbon tetrachloride–water interface are deduced as a function of CaCl2 and KCl ionic strength. Additionally, the role of the polymer backbone configuration in interfacial behavior is explored through isomer-specific studies. Results show that ion binding and charge screening induce the adsorption of the isotactic isomer of poly(methacrylic acid) to the oil–water interface under solution conditions unfavorable to surface adsorptivity and that the degree of cation–carboxylate interactions strongly affects the adsorption dynamics and interfacial structure of the adsorbed polymer. The backbone structure of syndiotactic poly(methacrylic acid) does not allow for strong interactions with cations, and therefore, it remains water-solvated in the presence of salt. This work has significance for understanding the role of metal ions in the assembly of natural charged macromolecules at biological and environmental interfaces.

Liquid–solid interfaces: structure and dynamics from spectroscopy and simulations

Liquid–solid interfaces: structure and dynamics from spectroscopy and simulations

Computational Modeling of Lauric Acid at the Organic–Water Interface

Where water meets an immiscible liquid, the orientation and hydrogen bonding patterns of the molecules nearest the interface differ significantly from those in the bulk. These differences drive important interface-specific phenomena, including interfacial tension and the adsorption of other molecular species. Additionally, surfactants and other amphiphilic molecules present at the interface interact with both the aqueous and hydrophobic layers in a complex fashion that can dramatically change the characteristics of the interface as a whole. In this study, classical molecular dynamics computer simulations have been employed to investigate the accommodation of lauric acid at the water–hexane and water–carbon tetrachloride interfaces. Our results show that the behavior of surfactant molecules in the interfacial region is strongly influenced by the protonation of their headgroups. Deprotonated lauric acid molecules cause a larger increase in interfacial width than their protonated counterparts. The carboxylate headgroups of laurate anions in the interfacial region consistently point toward the water layer, while the orientation of the protonated lauric acid headgroups changes with depth into the water layer.

Designated Drivers: The Differing Roles of Divalent Metal Ions in Surfactant Adsorption at the Oil–Water Interface

Divalent metal ions play numerous roles in biological, technological, and environmental systems. This study examines the role of a variety of ions, Mg(2+), Ca(2+), Mn(2+), Ni(2+), Cu(2+), and Zn(2+), in the adsorption of sodium decanoate at the carbon tetrachloride-water interface. For all ions studied, the ions drive the adsorption of the surfactant to the interface. Using vibrational sum-frequency spectroscopy and the carboxylic acid vibrational modes as a signature for metal ion binding, each metal salt is found to play a distinctly different role in the molecular characteristics of surfactant adsorption at the interface. Additional spectroscopic studies of the methyl and methylene vibrations are monitored to track the ordering of the alkyl chains when metal salts are added to solution. How the metal-surfactant binding impacts the surfactant structure, orientation, and solvation is explored. How these spectroscopic measurements compare with the degree of adsorption as measured by interfacial tension data is presented.

In situ Raman spectroscopic study of hydrolysis of carbon tetrachloride in hot compressed water in a fused silica capillary reactor

The uncatalyzed hydrolysis of carbon tetrachloride (CCl4) in hot compressed water (HCW) in a fused silica capillary reactor (FSCR) was investigated with in situ Raman spectroscopy at reaction temperatures up to 300°C. The phase behavior of CCl4 in water during heating at 34.1–260.0°C was observed by a microscope, and images were recorded with a digital camera. The phase phenomena showed that the CCl4 gasified between 231.3 and 260.0°C during the heating process. The hydrolysis was monitored by tracking the in situ vapor-phase Raman signals for CCl4 and product CO2. Increases in the CO2 Raman peak area over time were correlated to the hydrolysis yield. The quenched liquid products were analyzed by gas chromatography–mass spectrometry and ion chromatography, and the results indicated that the only hydrolysis products were HCl and CO2. The effect of the gasified CCl4 initial concentration (0.076–0.145g/cm3), CCl4(l):H2O(l) volume ratio (1:2, 1:6, 1:10), and reaction temperature (240–300°C) on the hydrolysis rate was investigated. The CCl4 hydrolysis in the FSCR was found to be mainly a vapor phase reaction. Temperature was the prime determining factor for the hydrolysis rate. The CCl4 hydrolysis rate was also dependent on the initial concentration of vapor-phase CCl4 and the initial CCl4(l):H2O(l) volume ratio. The kinetics of CO2 formation was analyzed, and the result showed that it followed the first order with an activation energy of 95.06±6.71kJmol−1.

Investigation of the liquid–liquid interface with high spatial resolution using near-field Raman spectroscopy

Local spectroscopic investigation of liquid–liquid interfaces and their surroundings is experimentally challenging. Highly localized illumination by a near-field optical probe is a possibility, but precise positioning of the probe very close to such an interface prior to measurement has been very difficult. Here, we show how this difficulty is overcome with greatly improved instrumentation. Near-field Raman spectroscopy was used to study the water–carbon tetrachloride interface with a spatial resolution of 200 nm. A blue shift of the OH stretching vibration of water was observed when approaching the interface, indicative a weaker H-bond in the vicinity of the apolar CCl 4.

Organic Phase Retention in CCC: Effect of Temperature, Tubing Material, Tubing Bore, Mobile Phase Flow, and the Addition of an Extraction Agent

This paper describes an investigation of organic phase retention and how it is affected by changing certain variables that are in the control of the user. A binary approach is taken in order to perform a quick evaluation of how key factors, like the addition of an extraction agent or a change of temperature, flow, tubing material, and bore affect stationary phase retention. Several different phase systems were studied in this way (decane–water, chloroform–water, methylisobutylketone–water, and carbon tetrachloride–water). The results show that retention is higher and more stable for larger bore tubing, and that at the analytical scale, there are threshold affects at low rotational speeds, which can create significant differences in retention behavior.

Membrane disordering induced by chloroform and carbon tetrachloride

We studied effects of chloroform and carbon tetrachloride on bilayer membranes of dimyristoyl-phosphatidylcholine (DMPC) and egg yolk phosphatidylcholine (Egg-PC) by birefringence, dynamic light scattering and fluorescence methods. It is shown that interference light due to the membrane birefringence considerably decreases by addition of the organohalogen compounds for both lipid membranes, indicating a significant decrease in membrane order. In addition, results of dynamic light scattering and turbidity measurements show a rupture of multilamellar DMPC vesicles induced by addition of chloroform at concentrations above 0.2 v/v%. No rupture of the vesicles is observed within the limit of solubility of carbon tetrachloride in water, but excessive addition of carbon tetrachloride (above 0.2 v/v%) induces the vesicle rupture. Chain orientational order was estimated from the interference light intensity at low concentrations of the organohalogen compounds without the occurrence of the vesicle rupture. The estimation shows a monotonic decrease in the chain order with increasing the concentration. The decreases in DMPC chain order by chloroform and by carbon tetrachloride are about 17% at 0.2 v/v% and 23% at 0.05 v/v%, respectively. The reduction in the chain order is correlated with an increase in the membrane fluidity observed by excimer fluorescence of pyrene incorporated to the membrane. Behavior of membrane disordering of Egg-PC is approximately similar with that of DMPC. This implies the strong interaction between the organohalogen compounds and the lipid chains, whether or not the bilayer has the vacancy resulted from unsaturated double bonds and different chains in length. The results of this work suggest that damages of biological membranes by chloroform and tetrachloride are not only induced by a direct attack on proteins but also by a significant membrane disorder.

Mass transfer coefficients in liquid–liquid extraction

The paper concerns with mass transfer in liquid–liquid extraction, considering that the experimental determination of the individual mass transfer coefficients during liquid–liquid extraction is still considered to be a difficult problem. In this work, the liquid–liquid extraction using a ternary system, water–acetone–carbon tetrachloride, was studied. The investigations were performed in an improved Lewis cell, in continuous and batch operation modes. The immiscible components (water–carbon tetrachloride) were mixed separately, while the acetone transfer was carried out in the two directions through an interface with a constant area of the surface, created between the two phases. The specific fluxes, the driving forces and the individual and overall mass transfer coefficients were determined by measuring the inflow and outflow acetone concentrations in the two phases, together with the equilibrium data. The values of the individual mass transfer coefficients in each phase were correlated and expressed in the form of criterial equation, as Sh= bRe p Sc m.

Induced changes in solvent structure by phospholipid monolayer formation at a liquid–liquid interface

Vibrational sum frequency spectroscopy has been used in conjunction with dynamic surface tension measurements to study formation of a 1,2-dilauroyl- sn-phosphatidylcholine (DLPC) monolayer at a water–carbon tetrachloride interface. Surface tension measurements show that an aqueous solution of liquid crystalline phosphocholine vesicles (4.5 μM DLPC) requires several hours to form a tightly packed, fully equilibrated monolayer of DLPC monomers. Vibrational spectra of the interfacial region at different stages in the monolayer formation process indicate that the solvent structure undergoes dramatic re-organization as the monolayer forms. Initial adsorption of DLPC monomers severely disrupts the interfacial hydrogen bonding. Intensity in the OH stretching region oscillates in a systematic fashion during the first 2 h of monolayer formation before finally settling to a level characteristic of the fully equilibrated monolayer. Frequency shifts of the OH stretching vibration show that water molecules with their C 2 axes aligned parallel to the interface experience a markedly different environment than those water molecules aligned perpendicular to the interface. This difference is attributed to the effect of the adsorbed, zwitterionic DLPC head-groups which, if aligned parallel to the interface, can stabilize in-plane water molecules.