Aromatic Sulphonation Research Articles

Relevant approach to assess performances of wastewater biosolids composting in terms of micropollutants removal

The presence of organic pollutants in wastewater biosolids and their possible impact to the environment contribute to decrease interest for the agricultural spreading of biosolids. It is thus important to have a better overview of sewage sludge quality in terms of organic pollutant content and ecotoxicity assessment. It is also necessary to better understand the impact of biosolid composting processes on the pollutant and toxicity removal. Therefore, concentrations of oestrogens (E), nonyphenol ethoxylates (NPE), polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and linear alkyl benzene sulphonates (LAS) and some of their associated toxic effects were determined at different stages of a composting process using, respectively, chemical analysis and in vitro bioassays (estrogen receptor alpha, dioxin receptor and pregnan X receptor reporter cell lines). Pollutants concentrations were higher in the final compost than in biosolid due to dry matter reduction through composting. Mass balance calculation shows a positive impact of the aerobic treatment on the removal of the most degradable pollutants. The three toxicological activities were measured in both biosolids and in the initial and final compost: oestrogenic activity increased whereas dioxin-like and pregnan X activities decreased. The difficulty in correlating chemical and toxicological results underlines the importance of combining both approaches in order to improve the assessment of the compost quality.

Behaviour of polynuclear aryl sulphonates

A series of hexadecyl polynuclear aromatic, decalin, and tetralin sulphonates have been synthesised. The critical micelle concentration (CMC) and surface and interfacial tension values at various concentrations above and below the CMC in both aqueous and non-aqueous media have been determined. The micellar size and shape, the average number of monomers constituting these micelles, and the thermodynamic properties have also been estimated. These studies show that the CMC value in both aqueous and heptane media decreases with an increase in the number of aromatic rings in the sulphonates. The size and shape of the micelles do not change appreciably in heptane, although the number of monomers constituting the micelles changes with a change of structure of the aromatic moiety. The thermodynamic parameters do not seem to affect the surface activity and solubilising properties even though the free energy, enthalpy, and entropy decrease with an increase in the size of the aromatic moiety. The surface and interfacial tension values are the lowest with aqueous and non-aqueous solutions of hexadecyl naphthalene sulphonate, but these values increase with an increase in the number of aromatic rings in the sulphonates. The sizes of the micelles of hexadecyl naphthalene sulphonate in aqueous solutions and the number of monomer molecules constituting the micelles are greater than for the other aromatic sulphonates. Although the sizes of micelles of hexadecyl benzanthracene sulphonate and hexadecyl pentacene sulphonate are comparable, the numbers of molecules constituting these micelles are the smallest. The solubilisation of alkanes in aqueous solutions of sodium naphthalene sulphonate containing electrolyte and isobutanol is the highest, but it falls off rapidly for all the other sulphonates. This shows the extreme sensitivity of solubilisation to the structure of the sulphonates. The detergency increases with an increase in the size of the aromatic moiety. The structure thus has a profound influence on the surface and micellar properties of these sulphonates. These studies are important from the point of view of the use of synthetic sulphonates as additives / surfactants in place of petroleum sulphonates.

A Nonempirical Quantum-Chemical Study and Natural Bond Orbital Analysis of C6H5XCY3Species (X = SO or SO2, Y = H or F)

The potential functions of internal rotation about the C2 sp—S bonds for C6H5XCY3 species (X = SO or SO2, Y = H or F) have been obtained at the MP2 (full)/6-31+G(d) level of ab initio theory. It is found that the spatial structures with the plane of C2 sp—S—C3 sp bonds, which is near perpendicular to the benzene ring plane, are the energy-favourable conformations. The values of the rotational barrier about the C2 sp—S bond are equal to (kJ/mole): 21.2 (C6H5SOCH3), 29.0 (C6H5SOCF3), 20.4 (C6H5SO2CH3), and 28.2 (C6H5SO2CF3). On the basis of the Natural Bond Orbital (NBO) analysis results, it has been revealed that the double S=O bond is a strongly polarized covalent σ-bond, whereas π-bond electrons practically are localized on the oxygen atom. The S=O bond order for aromatic sulfoxides and sulphones is mainly caused by hyperconjugational interactions according to the LP(O) → σ*(S—Cipso) and LP(O) → σ*(S—C Y ) mechanisms. In sulphones there is also the additional mechanism of hyperconjugational interactions such as LP(O1 → σ*(S—O2) and LP(O2) → σ*(S—O1). With the replacement of one hydrogen atom on the —XCY3 group, the charge loss of the unsubstituted benzene molecule increases: —SOCH3 < —SO2CH3 < — SOCF3 < —SO2CF3. The substitution of the —CH3 group for the —CF3 group weakly influences the charge value on the sulfur atom but effects the acceptor characteristics of the substituent to a greater extent than the variation of the sulfur atom coordination.

Electrochemical or UV-photochemical oxidation of industrial wastes containing polar aromatic sulphonates.

BACKGROUND AND INTENTION: Aromatic sulphonates other than surfactants and their hydroxy and amino-derivatives are important intermediates for the production of azo dyes. Their production on a large scale can be detrimental for the environment, if the by-products of their synthesis are not disposed of appropriately. An industrial waste, the organic components of which were mainly amino and hydroxy-substituted aromatic sulphonates, seriously endangers the environment close to an dismissed Italian industrial site. Inorganic sulphates and chlorides contained in the waste seriously hinder its disposal by incineration, since they corrode furnace walls. In this work, preliminary exploration of aqueous-phase electrochemically and photochemically induced oxidation techniques have been performed as possible alternatives to incineration. Electrochemically-induced oxidation was experimented on individual aromatic sulphonates and on an industrial waste by electrolysing them between smooth platinum electrodes at low temperature (5 degrees C) and high current densities (0.4 A/cm2) with aqueous 0.5 M NaHSO4 electrolyte. Photochemically-induced oxidation was performed by irradiating individual aromatic sulphonates or industrial waste with a 500 W mercury lamp in the presence of sodium peroxydisulphate. After 200 min electrodegradation, 90% of the original compounds disappeared, while 50% Total Organic Carbon (TOC) of an industrial waste was removed from solution after 10 hours. After 180 min UV-photodegradation, 90% of two test aromatic sulphonates disappeared, while 65% of TOC of industrial waste was removed after 5 hours. Two methods, electrochemical and UV-persulphate oxidation of an industrial waste, were used in order to propose a disposal procedure alternative to incineration. Electrodegradation with smooth Pt anode in 0.5 M NaHSO4 at 5 degrees C halved TOC concentration within 10 hours, while persulphate-assisted UV-photochemical oxidation with a 500 W high pressure Hg lamp abated two-thirds of TOC concentration after 5 hours. Energetic consumption of electrodegradation was 0.33 kWh/g TOC, while that of photooxidation was larger than 2 kWh/g TOC. Although both techniques can be considered efficient from a purely chemical point of view, since both are capable of wet-oxidising the aromatic sulphonates and the industrial waste, electrodegradation seems more promising than a photochemical degradation if economical considerations are also taken into account. Considering also that neither cell design nor catalyst were optimised in this preliminary study, the energy yield of electrodegradation seems likely to be largely improved.

Redox behavior of polyaniline as influenced by aromatic sulphonate anions: cyclic voltammetry and molecular modeling

We have investigated the influence of aromatic sulphonate anions on the redox behavior of polyaniline (PANI) by doping PANI, synthesized from sulphuric acid, with p-toluene sulphonic acid (pTSA), naphthalene sulphonic acid (NSA) and 5-sulphosalicylic acid (5-SSA). The contribution arising exclusively due to the anions was evaluated by keeping the concentration and the pH of the dopant solution constant at a value of 0.1 M and 2 respectively. The three aromatic sulphonate anions influenced the redox behavior of PANI differently. For instance, in the presence of NSA anions, PANI prefers to be in the protonated leucoemeraldine form, whereas at the same pH, PANI in the presence of sulphate, 5-SSA or pTSA anions, prefers to be in the unprotonated leucoemeraldine form. Interestingly, the presence of NSA gave highest stability to PANI against degradation due to hydrolysis. In order to rationalise these observations, molecular modeling (MM) studies were conducted. Using the molecular mechanics method, the energy of interaction between the dopant anion and the various forms of the polymer, namely, the leuco, emeraldine base, emeraldine salt and pernigraniline were estimated in order to take into account any factors other than just the basicity of the anion (e.g. non-covalent bonding interactions) that could contribute to the redox behavior of PANI. We have tried, for the first time, to correlate the redox peak positions with the interaction energies. The results of MM studies on this system are in good agreement with our experiments.

Genetic organization of sulphur-controlled aryl desulphonation in Pseudomonas putida S-313.

Pseudomonas putida S-313 is able to desulphonate a broad range of aromatic sulphonates to provide sulphur for growth by monooxygenolytic cleavage to yield the corresponding phenol. After miniTn5 transposon mutagenesis of this strain, 11 mutants were isolated that were no longer able to utilize benzenesulphonate as a sulphur source. Three of these mutants were defective in the utilization of all aromatic sulphonates tested, but they grew normally with other sulphur sources. These strains contained independent insertions in the novel 4.2 kb asfRABC gene cluster, encoding a putative reductase (AsfA), a ferredoxin (AsfB), a putative periplasmic binding protein (AsfC), which was localized to the periplasm using alkaline phosphatase fusions, and a divergently oriented fourth gene, asfR, that encoded a LysR-type regulator protein. A further mutant was interrupted in the ssu locus, which includes the gene for a putative desulphonative monooxygenase. Transformation of Pseudomonas aeruginosa with the asfRAB genes was sufficient to allow arylsulphonate utilization by this species, which does not normally use these compounds, suggesting that the AsfAB proteins may constitute an arylsulphonate-specific electron transport system that interacts with a less specific oxygenase. Expression of the asfABC genes in P. putida was induced by benzenesulphonate or toluenesulphonate, and it was repressed in the presence of sulphate in the growth medium. AsfR was a negative regulator of asfABC expression, and toluenesulphonate induced expression of these genes indirectly by reducing the expression of the asfR gene.

Evaluation of coelectroosmotic capillary zone electrophoresis for the rapid analysis of twelve aromatic sulphonate compounds

Coelectroosmotic capillary zone electrophoresis (CZE) has been investigated as a means of rapid analysis of twelve aromatic sulphonate compounds. The main factors affecting reversal of electroosmotic flow (EOF)—type of osmotic modifier and concentration-were studied. Two types of osmotic modifier, an alkylammonium salt (cetyltrimethylammonium bromide, CTAB) and a cationic polyelectrolyte (hexadimentrine bromide, HDB) were investigated. The composition of the running buffers was optimized according to the characteristics of each osmotic modifier. A concentration of HDB as low as 0.0001% (w/v) was used successfully to provide a stable and reversed EOF.

Generation of 275.4-nm UV output from a large-frame argon-ion laser for fluorescence detection in capillary electrophoresis

A standard, relatively old, large-frame argon-ion laser, which is available in many laboratories, was modified to produce output in the deep-UV (275–306 nm) region by installing a set of inexpensive, commercially available laser mirrors. The deep-UV output is generally applicable as excitation wavelength in the field of biochemical and environmental analysis. However, it has received little attention in the literature, probably because a complete laser set-up normally requires a high investment. The modification described, which includes a thorough cleaning of the Brewster windows of the laser tube and a careful alignment of the laser, is a good alternative to this investment. In daily operation, only some minor realignments are required. As an illustration of the applicability, excitation with the 275.4-nm line was used for laser-induced detection of native fluorescent aromatic sulphonates in capillary electrophoresis.

Comparative study of capillary zone electrophoresis and micellar electrokinetic chromatography for the separation of twelve aromatic sulphonate compounds

Two modes of capillary electrophoresis (CE), capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC), were investigated for the separation of 12 aromatic sulphonate compounds. In CZE, although the voltage applied, the buffer concentration and the pH were optimized for effective separation of the compounds studied, under the best conditions four of the five amino compounds coeluted, as did naphthalene-1-sulphonic acid and naphthalene-2-sulphonic acid. In MEKC, sodium dodecyl sulphate (SDS) and Brij 35 were chosen as the anionic and nonionic surfactants and the effect of the concentration of micelles was examined. The effect of adding methanol as the organic modifier was also investigated with each of these micellar systems. All the analytes, including the isomers, were completely separated by use of MEKC with Brij 35 but when SDS was used only 11 compounds were separated because two amino compounds coeluted.

Preparation of organostannanes by intermolecular radical substitution reactions

A new approach to the synthesis of aromatic stannanes via novel radical substitution reaction of aromatic sulfones is presented. Thus, α-heterocyclic aromatic sulphones derived from indole, pyrrole, pyrazole, furans and thiophenes undergo rapid and high yielding ipso-substitution to furnish organostannanes. This methodology has been extended to β-heterocyclic aromatic sulfones derived from indoline and dibenzofuran. The methodology has some liminations as shown in the lack of reactivity of 3-phenylsulfonyl indole derivative 17 and some phenylthio-substituted heteroaromatic systems 22–24. Phenylsulfinyl substituted indoles can also undergo the desired substitution reaction as shown in the successful transformation of 25 to the corresponding stannane 4a.

Determination of aromatic sulphonates in surface waters by high-performance liquid chromatography with coupled fluorescence and UV detection

An HPLC procedure for determining anthraquinonesulphonates in the presence of both benzene- and naphthalensulphonates in river water was developed. Enrichment of analytes was accomplished by means of solid-phase extraction, based on an RP-18 reversed-phase silica cartridge coated with an aliphatic amine. The analytes were separated by ion-pair chromatography with coupled fluorescence and UV detection, which resulted in a convenient way to discriminate derivatives of benzene and of naphthalene from those of anthraquinone. The peaks of anthraquinonesulphonates were identified by measuring the ratio of their absorbances at two different wavelengths. Four of the target analytes were found in water from the river Bormida (Italy).

Determination of sulphonic compounds as their thiotrifluoroacetate derivatives by gas chromatography with ion trap detection

A reductive method for the derivatization of sulphonates is described that is rapid (completed in a few minutes at room temperature) and uses mild conditions. Aromatic and aliphatic sulphonates were converted into the corresponding thiotrifluoroacetate derivatives using the reductive system sodium iodide-dimethylformamide-trifluoroacetic anhydride. 2-Amino-5-naphthol-7-sulphonic acid (J acid) was also derivatized successfully under the same conditions. All the derivatives were stable and could be separated easily by GC. The abundances of the molecular ion peaks were high on the ion trap detector and were convenient for identification.

A study of the adsorption of aromatic sulphonate anions at the gold (210) single-crystal electrode

The adsorption behaviour of benzenesulphonate (BS) and p-toluenesulphonate (PTS) anions at an Au(210) single-crystal electrode was investigated employing cyclic voltammetry and capacity measurements at constant ionic strength. It was found that the charge σ i due to specifically adsorbed anions is significantly greater (in the region of saturation) for the BS anion than for the PTS anion. It was postulated that BS anions can assume two different orientations at the electrode surface. A more detailed study of the adsorption process based on the Frumkin isotherm was performed for PTS anions. The inner-layer capacity was analysed into its components. The analysis indicated that the molecular structure of a given anion determines its behaviour during the adsorption process.

Adsorption of Foam-forming Surfactants In Berea Sandstone

Abstract Adsorption measurements carried out with representatives of four classes of surfactant suitable for foam flooding (alpha olefin sulphonate, internal olefin sulphonate, linear xylene sulphonate, and betaine) on Berea sandstone at different conditions of temperature and salinity are described. Adsorption of (he anionic surfactants from a low salinity brine is low, but increases substantially at moderate salinities. Limited solubility of the anionic surfactant in aqueous media tends to drive these surfactants to the solid/liquid interface and can also lead to increased surfactant loss through precipitation. The betaine is highly soluble, but adsorbs very strongly on sandstone. Adsorption of this surfactant can be reduced by mixing it with an anionic surfactant. Introduction EOR production in North America is dominated heavily by gas or vapor flooding. Out of total of 371 EOR projects, 294 involve injection of steam CO2 or hydrocarbon solvent(1). Became of the low density and viscosity of the injected fluid, gas and vapor flooding processes tend to suffer from poor sweep efficiency. This problem may be alleviated through the use of mobility control foams(2,3). While the mechanism of lamella generation and collapse is crucial to foam performance and propagation, the maximum distance that a foam will travel is dictated by surfactant loses in the reservoir, caused by adsorption at the solid/liquid interface, precipitation, chemical degradation, and partitioning into an immobile oil phase. This paper deals with the last and frequently most important of these mechanisms. Surfactant classes most commonly applied in laboratory studies of EOR-foams and in field applications include alkyl aromatic sulphonates and olefin sulphonates. Since much of the EOR-foam literature deals with steam foams, surfactant selection has often been determined by the requirement of chemical stability at steam flood temperatures. The following ranking has been assigned to several surfactant classe in terms of their thermal stability(4) alkyl aryl sulphonates &amp;gt; olefin sulphonates &amp;gt; petroleum sulphonates &amp;gt; ethoxylated alcohols and ethoxylated sulphates. The surfactants that have been found the most thermally stable are also the most likely to precipitate in the presence of inorganic electrolyte. Surfactant solubility has been found to decrease in the following order(4); ethoxylated alcohols or sulphates &amp;gt; olefin sulphonates &amp;gt; petroleum sulphonates = alkyl aryl sulphonates. A characteristic of the surfactants most commonly described in connection with EOR-foams is thus their limited solubility in brines. The high molecular weight surfactant homologues suitable for steam-foams have very limited solubility in aqueous media and are expected to have a higher affinity for the solid/liquid interface than lower molecular weight homologues. Steam flood temperatures will favour low adsorption levels and increased solubility. During steam flooding, a surfactant encounters salinity and temperature gradients and a knowledge of the dependence of surfactant behavior on both parameters is required. Surfactants suitable for the extreme conditions of salinity and hardness encountered in many Alberta reservoirs have been identified(5). Detailed measurements of the adsorption properties of these surfactants have been previously described(6–8). By contrast, reported adsorption data for surfactant classes commonly used for steam flood applications are rather limited(9–15).

Determination and identification by high-performance liquid chromatography and spectrofluorimetry of twenty-three aromatic sulphonates in natural waters

A method for detecting and identifying 23 aromatic sulphonates in natural waters was optimized. Samples were pretreated by solid-phase extraction in order to eliminate interferents and to preconcentrate the analytes. Separation of the extracted analytes was accomplished by ion-pair HPLC with fluorimetric detection; the eluent composition and pH were optimized. The detection limits lie in the low μg 1 −1 range. Some of the investigated compounds were found in the water of the river Bormida (N.W. Italy). Unknown components were identified from their fluorescence spectra.

The Use of H.P.L.C. in the Determination of Aromatic Sulphonates

The Use of H.P.L.C. in the Determination of Aromatic Sulphonates

Characterization of polypyrrole-fibre composites by time-of-flight secondary ion mass spectrometry and vibrational spectroscopy

We have examined polypyrrole-polyester and polypyrrole-quartz fibre composite samples using time-of-flight secondary ion mass spectrometry (TOF-SIMS). This technique has allowed us to confirm that in each composite the conducting polymer overlayer of cationic polypyrrole chains is doped with 5-sulphosalicylate dopant anions, at least to a sampling depth of 10 Å. Surprisingly there is no detectable presence of the second aromatic sulphonate dopant anion utilized in the Milliken synthetic procedure (1,5-naphthalenedisulphonic acid, disodium salt). Our Fourier transform ( FT) Raman spectra of these polypyrrole-fibre composite contain strong spectral bands due to the cationic polypyrrole chains, several weak features due to the underlying fibre substrate (particularly in the case of the polyester fibres), and no bands attributable to the dopant anions. These observations suggest that the Raman scattered light from the substrate component is largely reabsorbed by the polypyrrole overlayer. Thus we conclude that there must be extensive coverage of the fibre substrate by the conducting polymer with few, if any, ‘bare’ patches. Finally, our FTi.r. microscopy studies on these coated composites produced good quality spectra of the underlying substrate with few features attributable to the polypyrrole overlayers.

The cathodic scission of aromatic derivatives in the presence of nitrones as spin markers: on the reactivity of transient nitroxides in weak H-donor solvents: Part 2. On the cleavage of aromatic sulphones and halides in benzonitrile

Aromatic sulphones and some aromatic halides are reduced electrochemically directly and indirectly in benzonitrile in the presence of tert-butylphenylnitrone as a spin trap. In most cases, three line spectra are obtained in ESR attesting to the presence and the addition of free radicals, the nature of which is discussed.

Ion-exchange chromatographic determination of anions by indirect photometric detection: comparison of eluent ions with respect to sensitivity enhancement

Download options Please wait... Article information DOI https://doi.org/10.1039/AN9911600695 Article type Paper Download Citation Analyst, 1991,116, 695-700 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Ion-exchange chromatographic determination of anions by indirect photometric detection: comparison of eluent ions with respect to sensitivity enhancement S. Motomizu, M. Oshima and T. Hironaka, Analyst, 1991, 116, 695 DOI: 10.1039/AN9911600695 To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Shoji Motomizu Mitsuko Oshima Takashi Hironaka

Gas chromatographic method for the assay of aliphatic and aromatic sulphonates as their tert.-butyldimethylsilyl derivatives

A gas—liquid chromatographic procedure is described which permicts analysis of aliphatic and aromatic sulphonates as their tert.-butyldimethylsilyl dervatives. The tert.-butyldimethylsilylation of sulphonic acids in their free or sodium salt form is accomplished in a single derivatization step with N-methyl-N-( tert.-butyldimethylsilyl) trifluoroacetamide and tert.-butyldimethylchlorosilane in acetonitrile. Stablity results and mass spectral analysis of all tert.-butyldimethylsilyl sulphonates are presented. Each derivative displays a prominent and characteristic [M—57] fragment ion in its mass spectrum.