Analysis of BTEX, PAHs and metals in the oilfield produced water in the State of Sergipe, Brazil

During oil and gas exploitation, large amounts of produced water are generated. This water has to be analyzed with relation to the chemical composition to deduce the environmental impact of its discharge after a treatment process. Therefore, a study was carried out to evaluate preliminarily the BTEX (benzene, toluene, ethylbenzene and xylenes), polycyclic aromatic hydrocarbons (PAHs) and metals contents in produced water samples taken from effluents of the Bonsucesso treatment plant located in the city of Carmópolis, the most important oil and gas producer in the State of Sergipe, North-east of Brazil. Three methods were optimized to determine the target compounds. Polycyclic aromatic hydrocarbons were determined by gas chromatography with mass spectrometric detection (GC/MS), volatile aromatic hydrocarbons (BTEX) by gas chromatography with photoionization detector (GC/PID) and metals were analyzed by flame atomic absorption spectrometry (FAAS). The results showed that concentrations of the target compounds in these samples ranged from 96.7 to 1397 μg L^− 1 for BTEX, from 0.9 to 10.3 μg L^− 1 for PAHs and from 0.003 to 4540 mg L^− 1 for metals.     

Determination of Petroleum Products in Water by Measuring Integral Intensities of νCH Absorption Bands with a Fourier-Transform IR Spectrophotometric Complex

A new method was proposed on the basis of computer-assisted IR spectrometry for the separate determination of aliphatic (Alk) and aromatic (Ar) petroleum products in water samples. The integral intensities of absorption bands were measured with a Fourier-transform IR spectrophotometric complex. A series of individual hydrocarbons and their mixtures was studied, and real water samples were analyzed. The conditions for recording and computer processing of IR spectra were selected. Based on the published data and experimental data obtained using reference samples, optimal regions for recording IR spectra were characterized, and integration intervals were found for characteristic band areas of aromatic and aliphatic hydrocarbons. Regression equations were derived on an assumption that the system is binary. Working coefficients in the Bouguer–Lambert–Beer's law were found. Interval estimates of errors in the proposed method were calculated. Practical recommendations were given.     

FTIR imaging investigation in MIR and in an enlarged MIR-NIR spectral range

The study of polished cross sections is a well-assessed and practical method to investigate the stratigraphy of paintings and multilayer polychromies on works of art, in general. Analyses on cross sections allow us to characterize, at once, all the layers in the stratigraphy, giving information about the artists technique, the number of layers and their composition and sometimes about the conservation history of the artefact. In this paper, the application of an imaging detector focal plane array (FPA) coupled to an infrared (IR) microscope has been studied, focusing on the characteristics and potential of the different working methodologies (attenuated total reflectance (ATR) and total reflection). FPA detector coupled with ATR crystal can “localize” IR information coming from a 30 × 30μm sample area, in a 64 × 64 dot matrix detector. In particular, an innovative analysis methodology has been tested for the total reflectance measurements in order to obtain maximum information with single measurements. Micro-infrared total reflection measurements have been carried out in an extended IR range (from 1,000 to 5,266 cm⁻¹) exploiting the broad spectral response of mercury cadmium telluride detector in order to include overtones and combination bands from near-infrared spectral range without any modification of the standard mid-infrared micro-FT instrumentation. The potentialities of this new approach have been successfully transferred in the imaging/mapping investigations with a minimal tuning of the apparatus. Results obtained on a polished cross section coming from a modern painting and on a micro-sample of a wood polychromy from an undated historic polyptic are shown for demonstration.     

Catalytic Properties of ZrO2 Systems in the Reduction of Nitrogen Oxides by Hydrocarbons

The catalytic properties of zirconia prepared by different methods with impregnated variable-valence metals (chromium, cobalt, and cerium) as well as rhodium-promoted samples were studied in the reduction of nitrogen oxides by C₁ and C₃–C₄ hydrocarbons and also in the presence of sulfur dioxide. TPDA and IR spectroscopy showed that the different catalytic behavior of the Me _x O _y /ZrO₂ samples is related to their acid properties. The more active samples had strong Brönsted acid sites.     

Quantum calculations on the adsorption of halide ions on the noble metals

The interaction of halide ions with the three noble metals has been investigated using the B3LYP density functional method and the cluster model approximation. The results of calculations for the M—X⁻ and M₁₂—X⁻ (M = Cu, Ag, Au; X = F, Cl, Br, I) systems are presented. At the (100) surface, modeled in the present work by the M₁₂ cluster, all halide ions have been found to adsorb preferentially at the hollow site, followed by the bridge and by the top positions. The adsorption energy has been found to decrease when going from fluoride to iodide in both atom—ion and cluster—ion cases. The opposite trend is observed for the estimates of the charge transfer from the ions to the surface. When different metals are compared, the M₁₂—X⁻ interaction energies decrease in the order Au > Ag > Cu, but for the smaller ions some deviations from this line do appear. The relative values of the calculated harmonic vibrational frequencies do agree with those found experimentally, but their magnitude is much smaller as a result of the effect of the lower surface coverage.     

A study of complex equilibria of phenylglycine with nickel(II), copper(II) and zinc(II) in water and in water - methanol solution

The complex equilibria of the systems phenylglycine — nickel(II), copper(II) and zinc(II) in water and in water — methanol solution have been studied by computer analysis of potentiometric data. The mode of coordination has been established by¹³C-NMR and IR studies.

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Gleichgewichtsuntersuchungen der Komplexbildung von Phenylglycin mit Nickel(II), Kupfer(II) und Zink(II) in Wasser und Wasser - Methanol-Lösung

Zusammenfassung Anhand einer Computer-Analyse von potentiometrischen Daten wurden die Bildungsgleichgewichte in den Systemen Phenylglycin — Nickel(II), Kupfer(II) und Zink(II) untersucht. Der Koordinationstyp wurde mittels¹³C-NMR und IR festgestellt. Die Lösungsmittel waren Wasser und Wasser — Methanol.

     

Calculated vibrational spectra of weak hydrogen bonds

Potential energy and dipole moment surfaces for the H-bond SH... S in the dimeric methanethiol have been calculated by the SCF-MO-LCGO method, and the vibrational spectrum — transition frequencies and IR absorption intensities at 20 °K — computed. This spectrum is compared with that of the monomeric species and with experimental results. The resulting dimerization energy is 1.4 kcal/mole.     

Gaigranin and gaigrandin — New sesquiterpene lactones fromGaillardia grandiflora

Two new sesquiterpene lactones — gaigranin and gaigrandin — have been isolated from the epigeal part ofGaillardia grandiflora, and their structures have been established on the basis of spectral (IR, PMR,¹³C NMR, and mass) characteristics and x-ray structural analysis.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 79–85, January–February, 1995. Original article submitted October 7, 1994.     

Diterpenes ofLagochilus pubescens

Summary Compounds synthesized previously — di-O-isopropylidenelagochilin, di-O-acetyl-3,18-O-isopropylidenelagochilin, and 3,18-O-isopropylidenelagochilin — have been isolated for the first time from the plantLagochilus pubescens, and some supplementations have been made to their physicochemical constants.A new diterpene compound has been isolated for which, on the basis of IR, PMR, and mass spectra and chemical transformations, the structure of 16-O-acetyl-3,18-O-isopropylidenelagochilin is proposed.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 46–49, January–February, 1977.     

A new plant growth regulator of microbial origin

A new plant growth regulator — an inhibitor of the germination of mustard seeds — has been isolated from a culture filtrate of a phytopathogenic fungus of the genusPhoma. The methyl and trimethylsilyl derivatives of this compound have been obtained. Its empirical formula — C₁₆H₂₂O₅ — has been determined. On the basis of the results of IR and NMR spectroscopy and mass spectrometry, the compound isolated has been assigned the structure of 3,5-dihydroxy-2-octanoylphenylacetic acid.All-Union Scientific-Research Institute of Applied Molecular Biology and Genetics. V. I. Lenin Academy of Agricultural Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii No. 3, pp. 387–391, May–June, 1985.     

NMR study of alkaloids. V.13C NMR spectra and reconsideration of the structures of 11- and 10-hydroxypleiocarpamines and the structures of new alkaloids fromVinca erecta

The structures of phenolic alkaloids isolated previously fromVinca erecta Rgl. et Schmalh. have been reconsidered on the basis of the results of a study of their¹³C NMR spectra, and it has been shown that a base with mp 228–229° has the structure of 11-hydroxystrictamine and an amorphous base of the same composition isomeric with it is 10-hydroxystrictamine. The structures of two new indolenine alkaloids — ercinamine and ercinaminine — have been determined from an analysis of¹³C NMR spectra, and also on the basis of PMR and IR spectra and chemical transformations.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 483–488, July–August, 1983.     

Mono- and sesquiterpenoids of the oleoresins ofAbies sachalinensis,A. mayriana,andA. gracilis

The compositions of the mono- and sesquiterpenoids of the oleoresins of the Sakhalin fir (Abies sachalinensis Fr. Schmidt), Mayr's fir (Abies mayriana Miyabe et Kudo), and the slender fir (Abies gracilis Kom.) have been studied. In the oleoresin ofA. gracilis 37 compounds were identified, of which 11 were monoterpene hydrocarbons, seven were oxygen-containing monoterpenoids, 16 were sesquiterpene hydrocarbons, and three were sesquiterpene alcohols. In each of the oleoresins ofA. sachalinensis andA. mayriana eight oxidized monoterpenoids, 18 sesquiterpene hydrocarbons, and a sesquiterpene alcohol — bisabolol — were identified.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 195–199, March–April, 1980.     

Extraction of C60 from fullerene-containing carbon soots

Extraction of fullerene-containing carbon soots with various organic solvents has been studied at room temperature. Yields and compositions of toluene-soluble carbon soot fractions have been determined. Extracts of different carbon soot samples treated according to the toluene—trichlorobenzene—nitrobenzene scheme are studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1223–1225, July, 1995.The authors are grateful to E. B. Yagubskii and I. S. Krainskii for helpful discussion and help in the work.The work was financially supported by the Russian Foundation for Basic Research (Project No. 93-03-18705).     

Iridoid glycosides of plants of the genusIncarvillea I. 7-0-benzoyltecomoside fromIncarvillea olgae

Aucubin and five substances of iridoid nature designated as A, B, C, D, and E have been isolated from two species of plants — Lagotis integrifolia (Willd.) Schisk and Incarvillea olgae (Rgl.). The IR, UV, mass, PMR and¹³C NMR spectra of substance A have been studied, and an x-ray structural investigation has been made of its tetrahydro derivative. This has shown that substance A is 7-benzoyltecomoside.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 61–69, January–February, 1995. Original article submitted November 1, 1994.     

Material transport between the atmosphere and sediment of the Lake Balaton

A monitoring system was developed to gain information on the present level of pollutants in the Lake Balaton, Hungary. Determination of 13 polycyclic aromatic hydrocarbons (PAHs) and inorganic pollutants (mostly toxic metals) in aerosol, precipitation and sediment samples was carried out. The aim of collecting aerosol and precipitate samples in the same site at the same period was to determine the distribution of elements in two depositions. For the fractionation by particle size, aerosols were sampled by a cascade impactor. A simple three-stage sequential leaching procedure was applied to establish the distribution of metals among environmentally mobile, bound to carbonates and oxides, and environmentally immobile, (bound to silicates) fractions in aerosols. Sediment samples were collected from 17 different sites inside of the lake and 10 sites at harbors at 30–70 cm in depth. Core samples were cut to 10-cm pieces, dried at room temperature, and finally passed through a 63-μm sieve. Total concentrations of elements were determined by atomic absorption spectrometry (AAS) after an acidic digestion. The concentrations of PAHs were determined by HPLC method with fluorescence detection.In aerosol samples collected from September 6, 2002 to January 26, 2003, concentration of Cd was <0.1 μg/m³, and the majority of Cd has been found in the mobile fraction. Cadmium was associated to particles between 0.25 and 2 μm indicating the anthropogenic origin. Similar distribution of Pb was obtained in all seasons, and the highest concentration of Pb was found as 8.6 ng/m³ in particle size of 0.7 and 1.4 μm. Results of total concentration of elements of bottom sediments of the Lake Balaton and harbors were compared to Interim Sediment Quality Guideline (ISQG) values and the Probable Effect Level (PEL) values. Data showed that the average concentrations of elements were usually less than those of ISQGs and other background data for soils and geochemical values. The sediment is not polluted and its disposal is feasible. There is no direct correlation between the concentration of elements deposited onto the surface of the lake from dry and wet deposition and the upper part of the sediment. So, from the budget of the deposition, the concentration of elements in the upper layer of the sediment cannot be predicted.Seasonal changes of the concentration of PAHs in aerosol was observed, samples collected at winter contained the highest values. In December–January 2002/2003, the wet deposition was found as 64 μg/m² period. Among the individual compounds, the wet deposition rate of phenantrane, fluoranthene and pyrene was dominant, while for dry deposition, these compounds were fluoranthene and pyrene. The concentrations of ∑PAHs found for all sites and depth of sediment samples ranged from 11 to 1734 μg/kg dry weight with an average of 132 μg/kg. These values represent a quite low pollution level compared to other sediment with anthropogenic influence. Based on the results, it can be definitely confirmed that the chemical quality of the water and sediment of the Lake Balaton is satisfactory.     

An investigation by the NMR method of the structure of the alkaloid sophorine fromSophora alopecuroides

A new base — sophorine, with mp 59–60°C, [] _D ²³ -18.9° (c 0.98; ethanol) — has been isolated from the epigeal part of the plantSophora alopecuroides L. Its IR spectrum and the nature of its mass spectrometric composition have permitted sophorine to be assigned to the quinolizidine alkaloids. The¹³C NMR spectrum has shown the presence of 19 carbon atoms. The analysis of several of the carbon signals has confirmed the results of IR and mass spectroscopy. Additional details of the structure of sophorine have been obtained from its PMR spectrum.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 604–608, September–October, 1981.     

Influence of the position of the nitro group on the structural and spectroscopic characteristics of N"-(nitrobenzylidene)isonicotinic hydrazides in the crystalline state

N"-Substituted isonicotinic hydrazides of the general formula Py—C(=O)—N(H)-N"=C(H)—R, where R is o- (1), m- (2), or p-nitrophenyl (3), were studied by IR spectroscopy and X-ray diffraction analysis. The position of the nitro group in these compounds has no effect on the type of the crystal structure. The crystal packings are based on stacks consisting of antiparallel planar molecules. The molecules from the adjacent stacks are linked to each other via the N—H...N_Py hydrogen bonds. Depending on the position of the nitro group, the N...N_Py distance increases in the series 3 > 1 > 2 and the energy of the hydrogen bonds decreases (according to the IR spectroscopic data) from 3.9 to 3.1 kcal mol^–1. Analysis of the IR spectra demonstrated that the intensity of absorption in the (C—H) stretching region of the pyridine ring increases substantially as the the N—H...N_Py hydrogen bond is strengthened. Some regularities of the changes, which are observed for the (NO₂) bands in the spectra of the nitrophenyl-containing conjugated molecules in solutions, persist in the crystalline state.     

Thermal oxidation of poly(1-trimethylsilylprop-1-yne) studied by IR spectroscopy

Thermal oxidation of poly(1-trimethylsilylprop-1-yne) was studied by IR spectroscopy in the 20—245 °C temperature interval. In the 20—160 °C temperature range, the reaction proceeds predominantly at the C—Me group as revealed by the decrease in the intensity of the bands of the methyl group bound to the C atom and the appearance of the bands of the hydroperoxide and methylene groups. The decomposition of hydroperoxides produces aldehydes and ethers. At 160—200 °C, oxidation occurs via two routes: at the C—Me and C=C groups, while the Me₃Si group remains unchanged. At 230—240 °C, the rate of the reaction occurring at the C=C bond is higher than the rates of the processes involving the MeC and Me₃Si groups. The relative content of the structural units was calculated for the samples oxidized at different temperatures. Plausible mechanisms of thermal oxidation of poly(1-trimethylsilylprop-1-yne) were considered on the basis of the data obtained.