Addition Of SO3 Research Articles

Eu-doped carbon quantum dot as a selective probe for visualizing and monitoring sulfite in biological systems.

The detection of SO3 2- in complex environments and its visualization at the cellular level are critical for understanding its role in biological processes. In this study, we developed an Eu-doped long-wavelength fluorescent carbon quantum dot (CD2) and investigated the detection mechanism, interference effects and cellular imaging applications of the fluorescent probe CD2. The results show that the addition of SO3 2- induces an electronic rearrangement that restores CD2 to its original structure, leading to a rapid increase in fluorescence intensity. Selectivity experiments showed that CD2 has excellent selectivity to SO3 2-, with minimal interference from common anions. In addition, CD2 shows good biocompatibility for cellular imaging applications, as evidenced by the high cell viability observed in HeLa cells. Using confocal microscopy, we detected a significant enhancement of red fluorescence in HeLa cells after addition of exogenous SO3 2-, demonstrating the potential of CD2 as a probe for monitoring cellular SO3 2- levels. These findings highlight the promise of CD2 as a selective SO3 2- detection probe in complex environments and its utility in cellular imaging studies. Further studies are necessary to fully exploit the potential of CD2 in various biological and biomedical applications.

Study on the composition and hydration properties at early stages of high-sodium Portland cement clinker under the synergistic effects of SO3

Cement kiln co-processing is a common carbon reduction strategy that has become increasingly popular in recent years. However, the disposal of Na2O-containing solid wastes and fuels has resulted in elevated Na2O content in clinker, leading to the generation of high-sodium Portland cement clinker. To address this issue, the addition of SO3 was investigated in this study to improve the performance of high-alkali clinker. The synergistic effects of SO3 and Na2O on the mineral composition and hydration properties of high-sodium Portland cement clinker were studied. Five clinkers with different SO3 concentrations were synthesized and characterized using various techniques, including X-ray diffraction (XRD) combined with the Rietveld method, X-ray fluorescence spectrometry (XRF), backscattered electrons-energy-dispersive spectrometry (BSE-EDS), isothermal calorimetry, laser particle size analyzer, and mechanical properties testing. The results indicate that Na2O cannot be trapped by SO3 to generate Na2SO4, and instead dissolves in clinker phases to stabilize Ca2SiO4-low temperature form of α polymorph (C2S-α’L) and Ca3Al2O6-orthorhombic (C3A-o). As the SO3 concentration increases, the content of Ca3SiO5 (C3S) decreases, while the proportion of Ca3SiO5-monoclinic-type1 (C3S-M1) increases. The amount of C3A-o remains in a constant range, with the Ca3Al2O6 (C3A) content exhibiting a declining trend. Striations in belite can be observed when the SO3 concentration reaches 0.719%. The hydration rate of high-sodium Portland cement is accelerated with the increase of SO3 content at the ages of 3 and 7 days, leading to an improvement in compressive strengths.

Influence of SO3 on the MnOx/TiO2 SCR catalyst for elemental mercury removal and the function of Fe modification

Elemental mercury (Hg0) is a highly hazardous pollutant of coal combustion. The low-temperature SCR catalyst of MnOx/TiO2 can efficiently remove Hg0 in coal-burning flue gas. Considering its sulfur sensitivity, the effect of SO3 on the catalytic efficiency of MnOx/TiO2 and Fe modified MnOx/TiO2 for Hg0 removal was investigated comprehensively for the first time. Characterizations of Hg-TPD and XPS were conducted to explore the catalytic mechanisms of Hg0 removal processes under different conditions. Hg0 removal efficiency of MnOx/TiO2 was inhibited irreversibly from 92% to approximately 60% with the addition of 50 ppm SO3 at 150 ℃, which resulted from the transformation of Mn4+ and chemisorbed oxygen to MnSO4. The existence of H2O would intensify the inhibitory effect. The inhibition almost disappeared and even converted to promotion as the temperature increased to 250 ℃ and above. Fe modification on MnOx/TiO2 improved the Hg0 removal performance in the presence of SO3. The addition of SO3 caused only a slight inhibition of 1.9% on Hg0 removal efficiency of Fe modified MnOx/TiO2 in simulated coal-fired flue gas, and the efficiency maintained good stability during a 12 h experimental period. This work would be conducive to the future application of MnOx/TiO2 for synergistic Hg0 removal.

Controlled Reduction of Graphene Oxide Using Sulfuric Acid.

Sulfuric acid under different concentrations and with the addition of SO3 (fuming sulfuric acid) was studied as a reducing agent for the production of reduced graphene oxide (RGO). Three concentrations of sulfuric acid (1.5, 5, and 12 M), as well as 12 M with 30% SO3, were used. The reduction of graphene oxide increased with H2SO4 concentration as observed by Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy. It was observed that GO lost primarily epoxide functional groups from 40.4 to 9.7% and obtaining 69.8% carbon when using 12 M H2SO4, without leaving sulfur doping. Additionally, the appearance of hexagonal domain structures observed in transmission electron microscopy and analyzed by selected area electron diffraction patterns confirmed the improvement in graphitization. Although the addition of SO3 in H2SO4 improved the GO reduction with 74% carbon, as measured by XPS, the use of SO3 introduced sulfur doping of 1.3%. RGO produced with sulfuric acid was compared with a sample obtained via ultraviolet (UV) irradiation, a very common reduction route, by observing that the RGO produced with sulfuric acid had a higher C/O ratio than the material reduced by UV irradiation. This work showed that sulfuric acid can be used as a single-step reducing agent for RGO without sulfur contamination.

Comparative study on the resistance of different catalysts to electrochemical damage of fuel cells

This paper studies the catalytic performance and resistance to electrochemical damage of different catalysts in fuel cells by DFT calculations. The most commonly used platinum particle catalysts (Pt (111) surface) and three kinds of graphene-based platinum single-atom catalysts (G-N1-Pt, G-N2-Pt and G-N4-Pt) are selected as research objects. Based on Norskov's classical electrochemical theory, the step diagrams of hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR) under the standard reaction conditions and the interference with the addition of SO3− groups are calculated. Combined with the actual adsorption situation in the intermediate steps of the reaction, the catalytic performance of the standard reaction and the catalytic performance under the interference of SO3− groups are compared. For HOR reaction and ORR reaction, the catalysts with the best catalytic ability and anti-interference ability are G-N1-Pt catalyst and G-N2-Pt catalyst, respectively. A catalyst selection principle that balances activation performance and anti-interference performance in fuel cells is proposed.

Hollow fiber membrane separation process in the presence of gaseous and particle impurities for post-combustion CO2 capture

ABSTRACTThe membrane separation process for CO2 capture can be interfered by the gaseous components and the fine particles in flue gas, especially in desulfurized flue gas. In this work, the pint-sized Polyimide(PI) hollow fiber membrane contactors were self-packed to investigate the membrane CO2 separation from flue gas containing fine particles and gaseous contaminants (SO2,SO3,H2O). First, the effects of SO2, SO3, water vapor, and gypsum particles on the CO2 capture were studied independently and synergistically. The results showed that the effect of SO2 on the membrane separation properties is indistinctive; however, the membrane performance was damaged seriously with the addition of SO3. The high humidity promoted the CO2 separation initially before inhibiting the PI membrane performance. Moreover, the decrease of the CO2/N2 selectivity and the permeation rate were accelerated with the coexistence of SO2. The membrane performance showed an obvious deterioration in the presence of gypsum particles, with a 21% decrease in the CO2/N2 selectivity and 51% decrease in the permeation rate. Furthermore, the gypsum particles exerted dramatic damage. Under the WFGD conditions, the combined effects of SO2, water vapor, and the gypsum particles influenced the stability of the membrane significantly. This tendency is mainly attributed to the deposition of fine particles and aerosol on the membrane surface, which occupied the effective area and enhanced the mass transfer resistance. This study of impurities’ influence could play an important role in further industrial application of membrane CO2 capture.

Mineral Composition and Performance of Phosphoaluminate Clinker with Addition of SO<sub>3</sub>

The effect of SO3 on the mineral composition and performance of phosphoaluminate clinker was investigated by means of XRD, IR and SEM. Also, the compressive strength of clinker was performed. The experimental results showed that a certain amount of SO3 would promote the formation of calcium phosphoaluminate mineral, which was good for the strength development of phosphoaluminate clinker. Moreover, the addition of SO3 was benefit to the formation of C4A3 in phosphoaluminate clinker. So, the 5% dosage clinker owns a good strength development.

Coloration Process in the Sulfonation of Fatty Acid Methyl Ester with Sulfur Trioxide

AbstractFatty acid methyl ester sulfonate (MES), an anionic surfactant suitable as a laundry detergent, is produced commercially by the direct sulfonation of fatty acid methyl ester (ME) with SO3. However, intense coloration occurs during the sulfonation process. The sulfonation of ME was performed through the addition of SO3 (SO3/ME molar ratio = 0.8–1.2) for 1–4 h and subsequent aging for 1 h at 80 °C. Even when the amount of unsaturated bonds in ME was reduced to give an iodine value (IV) of less than 0.01, coloration occurred during the sulfonation, making the unbleached product unsuitable for commercial use. The formation of olefinic units and SO2 was observed during the reaction, and the color of the reaction mixture was strongly correlated with their amounts. Further analysis confirmed that equimolar amounts of the olefinic unit and SO2 were formed, and the rate profiles of the formation of MES and SO2 agreed well with each other. From these observations, we concluded that the coloration of the reaction mixture was caused by oxidation of the alkyl chain with SO3 during the liberation of SO3 from the 1:2 adduct of ME and SO3, a key intermediate in the sulfonation process.

Syntheses of Novel Four Membered Rings Containing Oxygen and Sulphur as Heteroatoms

Abstract The cyclisation of an alkylidenesulphurtetrafluoride is shown. The addition of SO3 to SF5-substituted olefins yields in an unexpected ring formation. The new oxadithietanes are presented a...

Sulfonation of chlorine-containing polymers: Sulfonation of various model tert-alkyl chlorides

tert-Alkyl chlorides of the structure R-C(CH3)2Cl, where R-methyl, ethyl, tert-butyl, and neo-pentyl, were reacted with a stoichiometric quantity of acetyl sulfate at room temperature in methylene chloride diluent. Reaction conversion was monitored as a function of time using 1H NMR; structure of the sulfonated products was characterized using 1H and 13C NMR. Reactivity toward sulfonation increased with increasing size of the R group. In all cases the structure of the products was the same as would be expected from sulfonation of the olefin which results from dehydrochlorination of the tert-chloride. The observed behavior was consistent with a mechanism involving dehydrochlorination followed by addition of SO3 to yield a zwitterionic intermediate. Depending upon structure, the zwitterion may either eliminate a proton to form one or more isomeric β,γ-unsaturated sulfonic acids, or it may rearrange to form a five-membered γ-sultone. This chemistry, which is particularly useful in the synthesis of ionomers, represents a direct route to alkyl sulfonic acids when the alkyl halide is the natural starting point in the synthesis.

Ozone and Sulfur Dioxide Effects on Tall fescue: I. Growth and Yield Responses

AbstractThe effects of ozone (O3) and sulfur dioxide (SO2) on growth and yield components of tall fescue (Festuca arundinacea Schreb. ‘Alta’) were studied in a greenhouse experiment. Four O3 treatments ranging from 0 to 0.30 ppm in equally spaced intervals and two SO2 treatments, 0 and 0.10 ppm, were arranged factorially in a randomized complete block design utilizing three blocks. Each block was exposed to the pollutants 6 h/d, once a week, for 12 weeks. Statistical analysis was by analysis of variance and regression techniques.Ozone significantly affected root/shoot ratio and all dry weight fractions. A reduction of total dry weight of 52.5% was found due to 0.30 ppm O3. A cubic regression model of O3 concentration on total dry weight accounted for 93% of the variation in total dry weight. Partitioning the dry weight into shoot and root components revealed a reduction in shoot weight of up to 46% and a reduction in shoot weight of up to 46% and a reduction in root weight of up to 63.6% due to the high‐O3 treatment. Both variables had significant cubic regressions of O3 on dry weight with the cubic model accounting for 93 and 89% of the variation in shoot and root weights, respectively. Root/shoot ratio declined from 0.58 for control plants to 0.41 for plants exposed to 0.30 ppm O3. A significant cubic regression of O3 on root/shoot ratio accounted for 78% of the variation in this variable. Tiller weight was also affected adversely by O3 with a linear decrease (r2 = 0.85) of > 44% at the highest O3 level. SO2 also affected tall fescue, but not nearly as severely as O3. Total dry weight was reduced by 7.3% due to SO2. Root weight was decreased by 11%, but shoot weight was unaffected. Root/shoot ratio was lowered about 7% due to the pollutant. Weight per tiller was unaffected by SO2. Number of tillers was significantly reduced by an interaction of the two pollutants. Neither O3 or SO2 had an effect singly, but at the high O3 level, the addition of SO3 caused an 18.6% reduction in number of tillers. This was the only significant pollutant interaction noted.

Aromatic sulphonation. Part 73. Behaviour of three 9-alkylanthracenes containing one side-chain α-hydrogen in dioxan–SO3complex in dioxan as sulphonating medium

The reactions of 9-isopropyl-, 9-s-butyl-, and 9-cyclohexyl-anthracene with dioxan–SO3 in dioxan at 17 °C lead to three types of products, viz. 9-alkenylanthracenes (2), unsaturated sulphonic acids (3), and seven-membered ring sultones (4). The 9-alkenylanthracenes (2) result from a redox reaction between the 9-alkylanthracenes and SO3 and the unsaturated sulphonic acids (3) from the subsequent sulphonation of (2). The seven-membered ring sultones are formed from the σ-complex (resulting from addition of SO3 to the 10-position of the original substrate) by a 1,2-hydride shift from the side-chain C-α to C-9.

Aromatic sulphonation. Part XLIX. Sulphonation of anthracene and some meso-substituted hydrocarbon derivatives: mechanism of methyl side-chain sulphonation

The sulphonation of anthracene and 9-phenyl-, 9-methyl-, and 9,10-dimethyl-anthracene with dioxan–SO3 in dioxan has been studied at 40°. With all substrates substitution products and no addition products are formed. With the first two substrates sulphonation occurs predominantly at the meso-position, the substitution distribution being 66 ± 89-, 26 ± 31-, and 8 ± 2% 2-substitution with anthracene, and 67 ± 410- and 33 ± 4% 4-substitution with 9-phenylanthracene. With the meso-methylated anthracenes not ring but methyl substitution takes place, the only products being 9-anthrylmethanesulphonic acid with 9-methylanthracene, and 10-methyl-9-anthrylmethanesulphonic acid and 9,10-bis-sulphomethylanthracene with 9,10-dimethylanthracene. It is proposed that the methyl sulphonation occurs by initial addition of SO3 to the opposite meso-position and subsequent loss of SO3 from the methyl sulphonated σ-complex. A similar but more complex mechanism is proposed to explain the methyl sulphonation of 7-isopropyl-1,4-dimethylazulene.

Reactions d'addition nucléophile sur les cétones : Addition de l'hydroxylamine: Mise en évidence de facteurs steriques par la mésure de l'éffet isotopique sécondaire du deutérium

Resume The rates of addition of NH2OH, in water at 25°, to seventeen ketones and their α-deuterated homologs, have been measured. The secondary kinetic isotope effects are expressed by the ratio kH/kD. The reaction rates have been measured in an acidic medium, and in these conditions the rate determining step is the attack of the free nucleophile on the carbonyl group of the ketone. The isotope effects are discussed in terms of electronic and steric factors. For this reaction the transition state is “reactant-like”. as we have shown elsewhere. As already observed in the addition of SO3= ion, the hyperconjugative factor is still operating in this case; however due to the shortness of the incipient CN bond, two kinds of steric effects art superimposed on the hyperconjugation. These steric effects, that we have called “effet sterique d'approche” and “effet sterique de torsion”, stem from the interaction between the α CH bonds and the incipient nucleophile and are, generally, mutally exclusive. The “effet steriquc de torsion” can arise when the NH2OH molecule approaches the substrates along a line perpendicular to the plane of the CO group. In the other cases the “effet sterique d'approche” is operative.

Glasses in the Systems PbO-B2O3-SO3and ZnO-B2O3-SO3

In the systems PbO-B2O3-SO3 and ZnO-B2O3-SO3 clear and stable glasses containing upto about 20 mole per cent SOs were obtained. Unlike the borate glasses, thin films of sulphate-containing glasses show selective infra-red transmission around 12μ. Compared to the corresponding borate glasses, thermal expansion is higher. DC resistivity, dielectric constant and softening temperature do not change significantly by replacing B2O3 with SO3. Addition of SO3, improves resistance of lead glasses to water attack but deteriorates zinc glasses. Some of the glasses did not show any visible change after they were kept exposed to atmosphere for about a year.