Potassium Permanganate Concentration Research Articles

Kinetic study of permanganate oxidation of tetrachloroethylene at a high pH under acidic conditions

AbstractSince carbon compounds are the main component of dense nonaqueous phase liquids (DNAPLs), the end products of all in situ chemical oxidation (ISCO) will include carbon dioxide. If the production rate of carbon dioxide exceeds the capacity of water to remove the carbon dioxide, degassing will occur. The uncontrolled carbon dioxide gas may change the flow patterns, remobilize the pooled DNAPL, transport DNAPL vapor, and reduce the relative permeability to the aqueous phase. Under high pH buffered conditions, most of the carbon dioxide will be dissolved in water. In this study, potassium permanganate oxidation of tetrachloroethylene (PCE) was conducted using a sodium carbonate buffered solution (1 g/L, pH = 10.6 ± 0.1) at three different temperatures (5, 10, and 20°C) and three potassium permanganate concentrations (0.2, 1, and 5 g/L). Extensive kinetic studies suggest that the overall oxidation is a second‐order reaction and pseudo‐first‐order with respect to PCE and potassium permanganate, respectively. The second‐order rate constant and the activation energy were 0.028 ± 0.001 M−1s−1 at 20°C and 43.9 ± 2.85 kJ/M, respectively. This study provides a base for further experimental and field studies on potassium permanganate oxidation of PCE under natural or artificial high pH buffered conditions. © 2004 Wiley Periodicals, Inc.

A modification of the staining technique of reticular fibres for image analysis of the cardiac collagen network

Introduction Silver stain of reticular fibres demonstrates the fine structure of the cardiac collagen network. However, nuclei are also stained with current techniques, a drawback that makes computer image analysis difficult. To solve this problem our study was designed to modify Gomori's method. Reactive concentrations and action times represent the core of that modification. Only stromal tissue is stained. The technique was tested for repeatability and reproducibility to assess the precision of the measurement procedure in the assessment of myocardial collagen in a consecutive series of myocardial samples from patients with and without heart muscle disease. In addition, we checked the reliability of the method by comparing our results with the point-counting method (PCM). Methods The right ventricular myocardium was fixed in 10% buffered formaldehyde and routinely processed. Paraffin sections (4 μm) were stained with several modifications of Gomori's method. Variable concentrations of potassium permanganate, silver solutions and different oxidation times were tried. A field from each sample was digitized. Additionally, the technique was tested for repeatability and reproducibility. Results We obtained absence of background and nuclear staining together with a highly contrasted image of the collagen network with 3 min oxidation with 2% potassium permanganate and a silver concentration of 1% during 5 min. In this way, it was very easy to perform acquisition, thresholding and area measurement without any further manual processing of the image. Conclusions This technique appears very helpful for the quantitative study of the cardiac collagen network by means of computerized image analysis systems.

Sequential Injection Spectrophotometric Method for the Assay of Paracetamol in Drug Formulations

Sequential injection analysis technique was employed as a successfbl tool for titrimetric determination of paracetamol in drug formulation. The potential aspect of paracetamol to reduce the absorbance of potassium permanganate in sulfbric acid media was applied to develop an ideal spectrophotometric data. The super modified simplex computer program was operated to optimize the main reaction parameters such as sulfbric acid and potassium permanganate concentrations and the (3f) factorial design was employed for studying their interaction effects. This method was found to be optimum iii 1.79~1~-~ mol dm-3 potassium pem~anga~iate and 0.071 rmol dm-3 sulhric acid concentrations for the detection limit between 50 to 350 ppm. The results obtained showed an accurate outcome when statistically compared with the BP standard method. The method reveals no interferences fiom most of the added excipients in drug formulation.

Graft copolymerization of methyl methacrylate onto gelatin using KMnO4‐H2SO4 redox system

AbstractThe graft copolymerization of methyl methacrylate onto gelatin was studied using KMnO4‐H2SO4 redox system. The maximum graft yield of 64.5% was obtained at the potassium permanganate concentration of 2.00 × 10−3 mol/L and the optimum temperature of 50°C. Activation energy was calculated as 18.6 kcal/mol at the temperature interval of 40–70°C. The results of the thermogravimetric analysis showed that the degradation temperature of gelatin increased as a result of grafting. Moreover, some changes in the properties of methyl methacrylate‐grafted samples were also observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2836–2844, 2003

Graft mechanism of acrylonitrile onto starch by potassium permanganate

AbstractThe graft mechanism of acrylonitrile (AN) onto starch under the initiation of potassium permanganate was investigated. The relationships of the grafting rate and the concentrations of potassium permanganate, AN, and backbone starch, as well as the reaction temperature, were established. On this basis, the equation for the rate of the graft copolymerization was derived, and the apparent activation energy for the graft copolymerization was obtained. Through the study of the oxidation reaction of starch with manganic ions, the valence changes of manganic ions during the graft copolymerization, and the grafting ability of different starch derivatives, together with electron spin resonance analysis, the grafting mechanism for the graft copolymerization of AN onto starch under the initiation of potassium permanganate was determined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 146–152, 2003

Effect of Exposure to Potassium Permanganate on Stress Indicators in Channel Catfish Ictalurus punctatus

AbstractJuvenile channel catfish Ictulurus punctatus were exposed to 1× (0.44 mg/L), 3× (1.32 mg/L), or 5× (2.19 mg/L) the recommended therapeutic concentrations of waterborne potassium permanganate (KMnO4) for 36 h to determine the toxicity of the chemical. The fish were observed for 14 d after exposure. Gill, liver, and blood samples were collected before exposure, at 12, 24, and 36 h of exposure, and at 48‐h intervals for 14 d thereafter. Analysis of homogenized gill tissue showed a transient increase in manganese content that quickly disappeared once exposure was discontinued. Fish exposed to the 3× and 5× concentrations of KMnO4 experienced 9 and 50.6% mortality, respectively. Plasma cortisol was elevated more than ten‐fold at the 5× concentration. Both plasma chloride and osmolality were significantly reduced at the 3× and 5× concentrations but were unchanged at the 1×. Packed cell volumes (PCV) of whole blood rose significantly in response to 3× and 5× concentrations of KMnO4 Mortality may have been the result of blood electrolyte depletion as indicated by increased PCVs, loss of chloride, and reduced osmolality. All stress indicators measured, except PCV at the 5× concentration, were indistinguishable from unexposed controls within 48 h after exposure was discontinued. At the l× concentration (the concentration most like that employed in a disease treatment) no changes were observed in any stress indicators measured suggesting that KMnO4 may be safely used as a disease therapeutant for channel catfish.

Chemiluminescence method with potassium permanganate for the determination of organic pollutants in seawater.

A chemiluminescence method with potassium permanganate was developed for use as an indicator of organic pollutants in fresh water. This method could be applied to the determination of organic pollutants in seawater as well. However, the flow chemiluminescence method suffered from the interference of chloride ions at the same concentration of seawater because of the production of manganese dioxide in the oxidation of chloride ions with permanganate. The conditions (concentrations of potassium permanganate and sulfuric acid and sample volume, i.e. flow injection method) were chosen to minimize the interference of chloride ions. The chemiluminescence method shows a good correlation with the chemical oxygen demand method on fresh water added artificial sea salt and seawater samples. Natural seawater was analyzed by the chemiluminescence method. The results obtained were compared with those obtained by chemical oxygen demand under the alkaline condition and total organic carbon methods. The chemiluminescence method has higher sensitivity and reproducibility than the conventional chemical oxygen demand and total organic carbon methods.

Grafting of 2-(Dimethylamino)ethyl Methacrylate onto Potato Starch Using Potassium Permanganate/Sulfuric Acid Initiation System

Graft copolymerization of 2-(dimethylamino)ethyl methacrylate onto potato starch was carried out in an aqueous medium using a potassium permanganate/sulfuric acid initiation system. The grafting percentage and grafting efficiency were determined as functions of the concentrations of potassium permanganate, sulfuric acid and the monomer, and also polymerization temperature and time. The IR spectrum of the graft copolymer showed the peaks characteristic of the grafted chains. The grafting percentage and grafting efficiency increased and then decreased with increasing the concentrations of potassium permanganate, sulfuric acid, and the monomer, as well as polymerization temperature. The grafting reaction was characterized by an initial fast rate followed a lower rate which leveled off after a certain time. The overall activation energy for the grafting was estimated to be 66.9 kJ/mol.

Preparation and separation performance of a dynamically formed MnO 2 membrane

A homogeneous and dense MnO 2 membrane with separating performance of ultrafiltration (UF) and microfiltration (MF) was successfully prepared, taking a sintered porous polyethylene (PE) tube as the support of the dynamically formed membrane and potassium permanganate as membrane material. And through a series of experiments, the effects of the concentrations of potassium permanganate and sodium formate in the membrane-forming solution, pH of the membrane-forming solution and the pore size of the support on the formation and the separation performance of dynamic membranes were studied. As a result, the forming conditions of the dynamic MnO 2 membrane were acquired as follows: pore size of PE tube, 5–20 μm; pH of membrane-forming solution, 5–7; concentration of KMnO 4 in membrane-forming solution, 0.050–0.100g/L; ratio of KMnO 4 to HCOONa, 1:1.5 or so. The membranes were applied to treat the diatomite mineral processing wastewater and oil refinery wastewater with stable performance and over 98% of turbidity removal rate. In addition, 5 wt% HCl solution can be used for cleaning the MnO 2 membrane and regenerating a new membrane on the substrate PE tube.

Graft copolymerization of starch-AN initiated by potassium permanganate

The initiating ability of the potassium permanganate in the graft copolymerization of acrylonitrile onto starch was studied. The results indicate that the grafting parameters, such as concentrations of potassium permanganate, acrylonitrile, starch, and catalyst acids, all have significant effects on the graft copolymerization and the components of the graft copolymers, and this offers methods to adjust the properties of the graft copolymers. The sources of starch and corn starch derivatives both affected the components of the graft copolymers, which showed the influence of functional group on the grafting ability of starch. The preheat treatment and preoxidation of starch, as well as the adding sequence of the reactants all influenced the graft copolymerization, from which some suggestions about the grafting procession could be obtained. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1965–1972, 1998

Synthesis of poly(acrylamide)-starch and hydrolyzed starch graft copolymers as a size base material for cotton textiles

Rice starch was hydrolyzed with HCl to obtain starch with different molecular sizes. The original starch and hydrolyzed starches derived from it were independently graft copolymerized with acrylamide (Aam) using potassium permanganate/citric acid as initiator under different conditions of initiator and monomer concentration, polymerization time and temperature. The newly synthesized products were applied to sizing of cotton textiles to see their suitability for temporary improvement of physico-mechanical properties. The results reflect the following findings. The graft yield, expressed as nitrogen % of poly(acrylamide)-starch and hydrolyzed starch graft copolymers: (a) increased up to a certain value by increasing the potassium permanganate concentration and then levelled off; (b) increased by increasing the acrylamide concentration within the range studied: (c) increased by raising the polymerization temperature from 20 to 50 °C: further increases in the polymerization temperature to 60 °C are accompained by decreased grafting: (d) increased by raising the polymerization time up to 1 h and then levelled off; and (e) increased by increasing the extent of hydrolysis expressed as copper number. On the other hand, physico-mechanical properties of cotton textiles, such as tensile strength, elongation at break and abrasion resistance, were found to be highly enhanced when the copolymers derived from hydrolyzed starches were used as size base materials; while the lowest textile properties were found when the original starch was used as a sizing agent.

Grafting of Methacrylic Acid to Loomstate Viscose Fabric Using a Potassium Permanganate/Potassium Chlorate System

Loomstate viscose fabric was graft polymerized with methacrylic acid using a KMnO4/KClO3 redox system. The polymerization reaction was studied with respect to graft yield, homopolymer, total conversion and graft efficiency. It was found that the polymerization reaction depends on the concentrations of potassium permanganate, potassium chlorate, and methacrylic acid, as well as on material to liquor ratio, reaction time and temperature of polymerization.

Grafting of Methacrylic Acid to Loomstate Viscose Fabric Using a Potassium Permanganate/Potassium Chlorate System

Loomstate viscose fabric was graft polymerized with methacrylic acid using a KMnO4/KClO3 redox system. The polymerization reaction was studied with respect to graft yield, homopolymer, total conversion and graft efficiency. It was found that the polymerization reaction depends on the concentrations of potassium permanganate, potassium chlorate, and methacrylic acid, as well as on material to liquor ratio, reaction time and temperature of polymerization.

Aqueous polymerization of acrylamide by electrolitically generated KMnO4 organic acid redox systems

Polymerization of acrylamide was carried out with potassium permanganate–malonic acid, potassium permanganate–tartaric acid, and potassium permanganate–citric acid redox initiator systems with and without electrolysis. The effect of potassium permanganate concentration, acrylamide concentration, and temperature on the polymerization yield was studied and molecular weights of polymers were determined and compared with electrolytic conditions. At low concentrations of potassium permanganate, continuously supplying Mn(III) has an advantage over the noneelectrolytic method for which polymerization did not occur under these conditions. © 1996 John Wiley & Sons, Inc.

Concurrent grafting and dyeing of cotton with a acrylamide/potassium permanganate/citric acid system

Samples of loom‐state cotton fabric was treated with aqueous potassium permanganate solution at different concentrations in the presence of nonionic wetting agent. The samples were then washed and treated at various pH values using solutions containing different concentrations of acrylamide and citric acid, plus wetting agent and acid or direct dye at different times and temperatures. Critical fabric properties such as graft yield, colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend upon the concentrations of potassium permanganate, citric acid and acrylamide, as well as on the treatment pH and the duration of the treatment.

A system for polymerising acrylonitrile onto loomstate cotton fabric using potassium permanganate/citric acid

A novel chemical formulation for concurrent grafting and dyeing using a potassium permanganate/citric acid system to induce polymerisation of acrylonitrile onto loomstate cotton fabric is described. The critical properties of the fabric, such as graft yield, colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend upon the concentrations of potassium permanganate, citric acid and acrylonitrile, as well as pH of the treatment bath and the duration of the treatment.

Synthesis, Characterization and Properties of Polyacrylamide‐Starch Composites

AbstractPolyacrylamide‐starch composite was prepared by polymerization of maize or rice starch with acrylamide (Aam) using potassium permangante/citric acid initiation system. Major factors affecting the polymerization reaction were studied with a view to discover appropriate conditions for preparation of the composite. Results obtained imply that the total conversion (monomer converted to homopolymer and graft) increases by increasing concentrations of potassium permanganate from 0.5‐0.20%, citric acid from 0.1‐0.15 and acrylamide from 10‐30% ows. Polymerization can easily be carried out at 40°C for 6 min at pH 4 using a material to liquor ratio 1:25 under a stirring rate of 350 rpm. The results further imply (a) that the apparent viscosity of the composite increases by increasing Aam concentration irrespective of the rate of shear, (b) that for 30% Aam concentration the composite consists of 77.7% starch and 22.3% polyacrylamide of which 10.4% are grafted, (c) that the sizeability of polyacrylamide‐starch composites is much better than that of native starches, and (d) that the kind of starch not only determines the total conversion but also the composition of the composite.

Grafting of Acrylamide to Loomstate Cotton Fabric Using Potassium Permanganate-Thiourea Redox System

Graft polymerisation of acrylamide (Aam) to loomstate cotton fabric using a KMnO4 H2N-C-NH2 system was studied under a variety of conditions. The polymerisation reaction was studied with respect to graft yield, homopolymer total conversion and graft efficiency. Results indicated that the polymerisation reaction was found to depend upon the concentrations of potassium permanganate, thiourea and acrylamide, as well as upon the pH of the reaction medium, reaction time and temperature of polymerisation. Based on detailed investigation of these parameters, the optimal grafting was obtained with 0.04 g/1 kMnO4; 0.06 g/1 thiourea; pH 3; temperature 80°C and time 60 minutes.

Grafting of Acrylamide to Loomstate Cotton Fabric Using Potassium Permanganate-Thiourea Redox System

Graft polymerisation of acrylamide (Aam) to loomstate cotton fabric using a KMnO4 H2N-C-NH2 system was studied under a variety of conditions. The polymerisation reaction was studied with respect to graft yield, homopolymer total conversion and graft efficiency. Results indicated that the polymerisation reaction was found to depend upon the concentrations of potassium permanganate, thiourea and acrylamide, as well as upon the pH of the reaction medium, reaction time and temperature of polymerisation. Based on detailed investigation of these parameters, the optimal grafting was obtained with 0.04 g/1 kMnO4; 0.06 g/1 thiourea; pH 3; temperature 80°C and time 60 minutes.

Effects of varying salinities on the toxicity of potassium permanganate to larval and juvenile striped bass, Morone saxatilis (Walbaum)

. Eight-day-old striped bass, Morone saxatilus (Walbaum) larvae, and one-month-old juveniles were held in varying salinities and exposed to a range of concentrations of potassium permanganate. Lethal concentrations of potassium permanganate for 50% of the larval fish exposed for96h (96h LC50) were 1middot;02, 2 middot;11, 1 middot;41 and 1 middot;73mg/1 for salinities of 0, 3, 6and 9 g/l, respectively; The 96h LC50S for juveniles were 0 middot;96, 3 middot;26, 1 middot;63 and 1 middot;48 mg/l for salinities of 0, 5, 10 and 15g/l, respectively. There were significant differences in 96h LC50 values at different salinities for both life stages. The 96 h LC50 values derived for both life stages revealed a decrease in toxicity as salinity increased from 0 to 3–5g/l. Results indicated potassium permanganate to be toxic in fresh water to striped bass larvae and fingerlings at recommended treatment levels (3 middot;0mg/l).