Ppm Nickel Research Articles

Removal of chromium, copper and nickel by water hyacinth (Eichhornia Crassipes)

Water Hyacinth (Eichhornia crassipes) has demonstrated its ability to remove nutrients and other chemical elements from sewage and industrial effluents. In this study, 10.00 ppm chromium, 35.00 ppm copper and 14.00 ppm nickel solutions were used, and absorption ability of water hyacinth was observed. Due to the positive experimental results on the removal of chromium, copper and nickel, its seen that water hyacinth may be used for industrial effluents under conditions in Turkey.

Concentration threshold of non-occluded nickel exposure in nickel-sensitive individuals and controls with and without surfactant.

Most cases of primary nickel sensitization are caused by occluded exposure to nickel released from earrings, buttons, etc. Nickel-sensitive females are both domestically and occupationally exposed to trace amounts of nickel. The present study was designed to define the minimum eliciting threshold concentration of nickel exposure in previously nickel-sensitized individuals, after open application on normal forearm skin with and without surfactant. A dilution series of NiCl2, ranging from 0.1 to 4000 ppm nickel with and without 4% sodium lauryl sulfate, was applied to healthy volar forearm skin. None reacted with definite allergic reactions to 100 ppm and below. Follicular reactions were seen in the concentration range from 0.1-100 ppm in a few patients and 1 healthy control. The results are discussed in relation to consumer products containing 1-10 ppm nickel.

Bioleaching and bioprecipitation of nickel and iron from laterites

Leaching of silicate ores, particularly nickel laterites, with the aid of heterotrophic organisms has been briefly reviewed. Samples of laterite ores from Greece were characterised mineralogically and a number of microorganisms isolated from them. One of these organisms (code FI) was successfully acclimatized to 6400 ppm nickel. Samples of the high-grade Greek Kastoria nickel laterite were leached with sulphuric acid and a number of organic acids. Sulphuric and citric acids extracted over 60 and 40% of the contained nickel, respectively, but the other acids employed were less efficient leachants. Oxalic acid precipitated nickel oxalate. Roughly the same extraction of iron was observed. The main leaching parameter was confirmed to be hydrogen ion concentration, although complexation with organic anions was a contributor. Organism FI (a strain of Penicillium) was used in comparison with organisms from various culture collections to bioleach nickel from samples of the low-grade Greek Litharakia nickel laterite. The organisms were cultivated in a mixture of a sugar-based nutrient mineral medium and finely ground ore. Several penicillia and aspergilli leached 55–60% of the contained nickel and cobalt, and 25–35% of the iron when sucrose was the carbon source, but FI was not efficient. However, in molasses medium, Fl extracted nearly 40% of the nickel. Biosorption and bioprecipitation reactions were observed. The mechanism of bioleaching or in situ leaching is discussed in terms of close physical and chemical association between the fungal hyphae and mineral phases in the ore. This accounted for the low overall hydrogen ion concentration observed during bioleaching.

Bioleaching and bioprecipitation of nickel and iron from laterites

Leaching of silicate ores, particularly nickel laterites, with the aid of heterotrophic organisms has been briefly reviewed. Samples of laterite ores from Greece were characterised mineralogically and a number of microorganisms isolated from them. One of these organisms (code FI) was successfully acclimatized to 6400 ppm nickel. Samples of the high-grade Greek Kastoria nickel laterite were leached with sulphuric acid and a number of organic acids. Sulphuric and citric acids extracted over 60 and 40% of the contained nickel, respectively, but the other acids employed were less efficient leachants. Oxalic acid precipitated nickel oxalate. Roughly the same extraction of iron was observed. The main leaching parameter was confirmed to be hydrogen ion concentration, although complexation with organic anions was a contributor. Organism FI (a strain of Penicillium) was used in comparison with organisms from various culture collections to bioleach nickel from samples of the low-grade Greek Litharakia nickel laterite. The organisms were cultivated in a mixture of a sugar-based nutrient mineral medium and finely ground ore. Several penicillia and aspergilli leached 55–60% of the contained nickel and cobalt, and 25–35% of the iron when sucrose was the carbon source, but FI was not efficient. However, in molasses medium, Fl extracted nearly 40% of the nickel. Biosorption and bioprecipitation reactions were observed. The mechanism of bioleaching or in situ leaching is discussed in terms of close physical and chemical association between the fungal hyphae and mineral phases in the ore. This accounted for the low overall hydrogen ion concentration observed during bioleaching.

Ultrasonicvs. nonultrasonic hydrogenation in a batch reactor

Refined and bleached soybean oil was hydrogenated with and without ultrasonic energy in a batch system. Reactions were carried out at 170°C with 0.02% nickel catalyst (Nysel, Harshaw/Filtron Partnership, Cleveland, OH) or 50 ppm nickel in the oil. Hydrogen pressure was varied from 15 to 90 psig. After 20 min, the average reaction rate was about five times faster in the presence of ultrasonic energy. Hydrogenation rate generally increased with increasing hydrogen pressure when ultrasonic energy was applied. However, the increasing rate is more sinusoidal in nature than linear.

Nickel uptake by the water hyacinth

Abstract Factors influencing the uptake of Ni2+ by the water hyacinth (Eichhornia crassipes) were studied. In the concentration range of 1–1000 ppm nickel the uptake of nickel occurred in an initial rapid phase followed by a slower, near linear uptake phase. Plants subjected to multiple exposure to nickel solutions also exhibited these two uptake phases, but the ability to remove nickel from solution was reduced as the number of exposures increased Stirring the solution enhanced the uptake of nickel, suggesting that uptake was limited by diffusion. Increased root mass or solution volume increased the amount of nickel removed from solution. In the pH range of 4–10 the uptake of nickel was independent of pH. Competition with various metal ions was found to significantly reduce the uptake of nickel as did the presence of several complexing agents., Nickel initially bound to the hyacinth was partially released to a soloution containing EDTA.

Cracking catalysts deactivation by nickel and vanadium contaminants

This paper reports on the unsteady-state pulse technique applied to the catalytic cracking of gas oils with several commercial catalysts. Experimental runs were performed in a pulse microcatalytic fixed bed reactor to closely mimic the short contact times of commercial fluid catalytic cracking (FCC) riser reactors. Equilibrium catalyst was simulated by steaming in a fluidized bed, artificial impregnation with metal naphthenates under vacuum, and calcination. Analytical techniques were used to confirm the effectiveness of the artificial aging method. The poisoning effects of nickel and vanadium have been demonstrated on different catalysts through the changes obtained in overall conversions and product selectivities. The kinetic constants evaluated for a three- and a five-lump model clearly showed a decreasing trend, with the increment of metal loading being from 0 to 5000 ppm nickel equivalent. Moreover, the activation energies calculated presented a consistent tendency, decreasing with increasing metal concentration.

Effects of temperature, and dietary magnesium and nickel levels on magnesium and nickel concentrations during the moult - cycle inOniscus asellus(Porcellionidae, Isopoda, Crustacea)

Mean magnesium concentrations in intermoult Oniscus asellus, caged at 20 degrees C for 10 days, ranged from 1,059.15 +/- 51.9 ppm on diets containing 10 ppm nickel, to 6,827.6 +/- 314.1 ppm on a mixture of 500 ppm magnesium + 10 ppm nickel. Mean nickel concentrations ranged from 89.4 +/- 4.3 ppm on diets containing 500 ppm magnesium, to 314.0 +/- 14.8 ppm on a mixture of 500 ppm magnesium + 10 ppm nickel. At 30 degrees C, magnesium tissue concentrations ranged from 4,149.8 +/- 153.5 ppm on diets with 10 ppm nickel to 12,602.6 +/- 529.3 ppm on 500 ppm magnesium. Nickel concentrations at 30 degrees C varied from 156.8 +/- 6.7 in isopods in the control to 490.5 +/- 23.5 ppm on those on 500 ppm magnesium + 10 ppm nickel. Magnesium in intermoult isopods was mainly stored in other tissues, including the exoskeleton, and nickel in the hepatopancreas. Differences in both magnesium and nickel concentrations between males and females were not significant. Magnesium and nickel concentrations in postmoult isopods, on the average, amounted to 367.6 +/- 16.5 ppm and 18.7 +/- 0.7 ppm, respectively, at 20 degrees C, and 369.9 +/- 16.3 ppm and 30.9 +/- 1.3 ppm, respectively, at 30 degrees C. Differences between males and females, and between various treatments were not significant at P greater than 0.01. It is suggested that both hepatopancreas and other tissues, including the exoskeleton, are used as sinks to get rid of excessive tissue magnesium and nickel during the moult-cycle.

Ternary Complex Nickel(II)/3-(4′,5′-Dimethyl-2′-Thiazolylazo)-2,6-Dihydroxybenzoic Acid/Cyanide. Spectrophotometric Determination of Nickel

Abstract A spectrophotometric method for nickel has been developed based on the formation of a ternary complex in the system Ni(II)/3-(4′,5′-dimethyl-2′-thiazolylazo)-2,6-dihydroxybenzoic acid/cyanide at pH 9.2 (borate buffer), which allows the determination of 0.05–0.47ppm of nickel (e = 3.53×104 1.mol−1. cm−1) at 538nm. Interferences have been studied and the method applied to the determination of nickel in low alloy steels.

The accumulation and the effect of heavy metals on the water fern Azolla filiculoides

SUMMARY Azolla filiculoides Lamarck grown for 3‐7 days in nutrient media containing 8‐15 ppm of different heavy metals was found to contain about 10000 ppm cadmium, 1990 ppm chromium, 9000 ppm copper, 9000 ppm nickel and 6500 ppm zinc. The content of heavy metal in the roots was two‐ to five‐fold higher than in the shoots, and 98% of the heavy metals were bound to the insoluble fraction of the Azolla. The content of heavy metals in dead dried Azolla was 3–7 times higher than in the living plants. Zinc and cadmium were more readily transferred from the roots to the shoots than nickel, copper and chromium. Growth in the presence of the heavy metals resulted in severe leakage of K+, Mg2+ and Na+ ions from the roots with less leakage of Ca2+. The effect of heavy metals on the loss of K+, Na+ and Mg2+ from the shoots was more limited. Nitrogenase activity was almost completely inhibited by cadmium, nickel and zinc, while copper and chromium had less effect. Azolla may prove useful in the detoxification of industrial effluents.

Spectrophotometric determination of nickel in steels

AbstractNew, simple and sensitive spectrophotometric methods for the determination of nickel with hematoxylin in the presence and absence of a cationic surfactant are described. The sensitivity of the color reaction of nickel and hematoxylin is greatly increased by the sensitizing action of cetyltrimethylammonium bromide (CTAB). The optimum pH range for the formation of nickel‐hematoxylin and nickel‐hematoxylin‐CTAB systems is 7.8–8.3 and 7.4–8.1, respectively. The molar absorptivities are 4.1 × 104 and 8.3 × 104 mol−1 cm−1 at 595 and 608 nm, respectively. The corresponding values of Sandell's sensitivity index are 0.0014 and 0.0007 μg cm−2 of nickel. The methods adhere to Beer's law up to 0.52 and 0.60 ppm nickel, respectively. The mole ratio of nickel‐hematoxylin in both complexes is 1:2. Preliminary separation of nickel by extraction as dimethylglyoxime chelate into chloroform makes it possible to determine nickel in steel samples.

Continuous ultrasonic hydrogenation of soybean oil. II. Operating conditions and oil quality

AbstractIn previous work we found that ultrasonic energy greatly enhanced the rate of hydrogenation of soybean oil. We have now investigated parameters of ultrasonic hydrogenation and the quality of the resulting products. Refined and bleached soybean oil was hydrogenated continuously with and without ultrasonic energy at different temperatures, pressures and catalyst concentrations. Flavor and oxidative stability of the oils were compared with a commercially hydrogenated soybean oil. The extent of hydrogenation (ΔIV) was not affected by temperature between 245 and 290 C, but was greater at 106 psig than at 65 psig hydrogen pressure. The ΔIV of hydrogenated oils increased linearly with catalyst concentration from 40 ppm to 150 ppm nickel. At the same catalyst concentration the IV drop was significantly increased when ultrasonic energy was used. By reducing the amount of power supplied to the ultrasonic reactor to 40% of full power, the specific power (watts/ΔIV) was lowered by 60%. Linolenate selectivities and specific isomerization (%trans/ΔIV) remained the same, but linoleate selectivities were lower than for batch hydrogenation under varied operating parameters. Flavor scores were not significantly different, initially or after storage eight days at 60 C, for oils continuously hydrogenated with and without ultrasonic energy. Hydrogenation of soybean oil with ultrasonic energy offers a method to produce good quality products at potentially lower cost than present methods.

Cadmium and nickel in mainstream particulates of cigarettes containing tobacco grown on a low-cadmium soil-sludge mixture.

Cigarettes were prepared from tobaccos grown in the greenhouse on a soil to which a low rate of a municipal sewage sludge was applied. The cigarettes were smoked by machine and the mainstream particulate fraction was analyzed for total cadmium and nickel content. Sludge-grown and control (soil-grown) tobaccos contained, respectively, 5.33 and 1.87 ppm of cadmium and 1.15 and 0.64 ppm of nickel. The average quantities of cadmium and nickel (ng/cigarette) found in the mainstream particulate fractions were, respectively, 220.5 and 78.5 for the sludge-grown and 147.4 and 72.6 for the control treatments. The difference between treatments was highly significant (p less than 0.001) for cadmium but not significant for nickel.

Effect of Dietary Nickel on Growth, Urease Activity, Blood Parameters and Tissue Mineral Concentrations in the Neonatal Pig

Day-old pigs were individually fed a low nickel (0.16 ppm) liquid milk-based diet supplemented with either 0, 5 or 25 ppm nickel on a dry matter basis for a 21-day period. At the end of the liquid feeding period, five pigs per treatment were killed, and the remaining five were fed a dried skim milk-based diet (0.12 ppm nickel) with similar levels of added nickel for an additional 28 days. Dietary nickel did not affect animal gain, liver cholesterol, serum protein concentrations or bacterial urease activity in the gastrointestinal tract. The addition of 5 ppm nickel to the basal dry diet reduced ammonia concentrations in the cecum by 33%. Pigs receiving the high level of nickel had decreased serum alkaline phosphatase and increased serum glucose at 49 days, compared to controls. Animals receiving 5 ppm nickel had higher liver iron and zinc concentrations than controls at 21 days but not at 49 days. Control pigs had lower kidney and lung nickel concentrations than animals receiving 5 ppm nickel at 21 days but not at 49 days. Increasing dietary nickel from 5 to 25 ppm resulted in increased concentrations of nickel in serum, kidney, lung, spleen and muscle. These results suggest that 0.12–0.16 ppm nickel is adequate for growth of neonatal pigs fed milk-based diets. However, additional nickel may improve the iron and zinc status of the young pig.

Determination of some common trace impurities in chromium by X-ray fluorescence spectrometry

An X-ray fluorescence spectrometric method for the determination of calcium, iron, nickel, copper, molybdenum and lead in chromium has been developed. Five hundred mg sample in oxide form is made into a double layer pellet after mixing with boric acid binder. The analysis is done on a Philips PW 1220 spectrometer using a LiF (200) crystal for dispersion. The minimum determined concentration is 10 ppm for calcium, 20 ppm for nickel and 50 ppm for iron, copper, molybdenum and lead. Precision at each concentration of the standards and theoretical minimum detection limits have been calculated.

Influence of detergent washing powders on minimal eliciting patch test concentrations of nickel and chromium.

Minimum eliciting levels of nickel have been estimated in 25 nickel-sensitive subjects, and of chromium in 14 chromium-sensitive subjects by patch tests with aqueous solutions of the respective metals. The minimum level of each metal required to provoke a patch test reaction was considerably greater than that found in fabric washing powder solutions and was in the majority of patients tested of the order of 112 ppm nickel (0.05% nickel sulphate) or 885 ppm hexavalent chromium (0.25% potassium dichromate). One nickel-sensitive subject and one chromium-sensitive subject reacted to 1 ppm of the respective metal. Fabric washing powder did not significantly alter the patch test reaction to nickel sulphate or provoke reactions in nickel- or chromium-sensitive subjects. EDTA significantly reduced the number and severity of patch test reactions to nickel sulphate but not those to potassium dichromate or trivalent chromium.

Spectrophotometric determination of nickel with biacetyl bis(4-phenyl-3-thiosemicarbazone)

A simple method is described for the rapid spectrophotometric determination of nickel with biacetyl bis(4-phenyl-3-thiosemicarbazone). The yellow color is measured at 460 nm (ϵ = 22,800 liters mol −1 cm −1) against a reagent blank at pH 2.5 in a solution containing 60% ( v v ) dimethylformamide. Beer's law is obeyed over the range 0.2–2 ppm of nickel.

Selective spectrophotometric determination of nickel using phenanthrenequinone monothiosemicarbazone

The formation of 1∶3 (metal∶ligand) complex with phenanthrenequinone monothiosemicarbazone (PTS) has been used for the determination of 0.43-2.1 ppm of nickel(II) over the pH range 7.0–9.2 in 50% methanol medium. The complex shows maximum absorption at 520 nm with a sensitivity of 0.0023μg Ni/cm2. The selectivity of the method has been studied and the method has been employed for the determination of nickel in brightray G wire.

Cadmium and nickel in smoke of cigarettes prepared from tobacco cultured on municipal sludge-amended soil.

Cigarettes prepared from tobacco grown on municipal sludge-amended soil were smoked, and the mainstream particulates and gaseous fractions were analyzed for total cadmium and nickel content. Sludge-grown and control (soil-grown) tobaccos contained, respectively, 67.4 and 3.18 ppm of cadmium and 19.4 and 1.29 ppm of nickel. The quantities of cadmium (microgram per cigarette) found in the mainstream particulate and gaseous fractions were, respectively, 6.67 and 0.04 for the sludge-grown and 0.21 and 0.03 for the control treatments. The quantities of nickel (microgram per cigarette) found in the mainstream particulates and gaseous fractions were, respectively, 0.11 and 0.07 for the sludge-grown and 0.01 and 0.01 for the control treatments. The potential public health implications of these results and modifying factors are discussed.

Syntheses and spectrophotometric studies of 2-(2-thiazolylazo)- and 2-(2-benzothiazolylazo)-5-dimethylaminobenzoic acids as analytical reagents: Determination of nickel

2-(2-ThiazolyIazo)-5-dimethylaminobenzoic acid (TAMB) and 2-(2-benzothiazolylazo)-5-dimethylaminobenzoic acid (BTAMB) have been synthesized, and their potential for determinations of metals has been studied spectrophotometrically. Both are extremely sensitive chromogenic reagents for the determination of nickel. Molar absorptivities in aqueous methanol are 0.95 × 10 5 (TAMB) and 1.2 × 10 5 (BTAMB). In aqueous methanol, at apparent pH 5–9.5, the system conforms to Beer's law for 0.05–0.5 ppm nickel; Cu, Cr, Co, Pd and Fe interfere, but they can easily be masked.