Über die Sulfonierung von Olefinen – Einfluß der Reaktionsbedingungen und der Olefinstruktur auf die Sulfonierungsprodukte

Sulfonation of Olefins – Influence of Reaction Conditions and Structure of Olefins on the Products of Sulfonation Sulfonation of n-α-olefins with SO₃, which is not bound as complex, and the products resulting from these reactions are reported. Based on the course of sulfonation and the composition of the product, a reaction mechanism has been derived. The composition of the products obtained by sulfonation of α-olefins can be varied within certain limits by adjusting the conditions of sulfonation and treatment of the reaction products. Sulfonations of unbranched non-terminal olefins, olefins having monoalkyl branching at the double bond and of technical oligo-olefins have been reported.     

Sulfonation of polymer surfaces - II. Chemical changes on polypropylene and polystyrene surfaces after gas phase sulfonation

This study investigates the chemical changes effected on the surface of polypropylene and polystyrene as a result of sulfonation using an SO₃-air mixture (1% SO₃ v/v). Polypropylene is a purely aliphatic system and is characterized by the tertiary carbon which it has on its backbone. On the other hand, polystyrene is characterized by an aromatic ring on its backbone. Different surface analytical techniques (XPS, FTIR-ATR, and contact angle measurements) were used to quantify the changes. It was concluded that the formation of sulfonic acids was the main chemical change which occurred on the surfaces of polypropylene and polystyrene. Besides sulfonic acids, there was an indication of several side reactions occurring in the case of polypropylene while polystyrene did not show any such side reactions. The surfaces of both polymers reached a state of treatment saturation (~ 6.5% for polypropylene and 7% for polystyrene). Sulfonation of polypropylene beyond the saturation limit led to degradation, as manifested by a highly sulfonated layer of polypropylene which sloughed off during neutralization. However, intense sulfonation of polystyrene did not show any conspicuous degradation.     

Processing and packaging sulfonation and sulfation technology

The paper will summarize the sulfonation/sulfation process used in the detergent industry, with particular emphasis on the modern techniques involving the use of diluted gaseous SO₃ as a sulfonating agent. The outstanding features of the commercially available SO₃-air processes will be described, and the Ballestra, Berol, Allied, Chemithon, and Mazzoni reactors will be shown graphically in figures. The particular aspects of processing the various feedstocks, decomposition of the by-product anhydrides in sulfonation of alkylbenzene, hydrolysis of the sultones formed in sulfonation of alpha olefins, and their implication on the integrated sulfonation processes are also considered.     

Ethersulfonate auf Basis ungesättigter Fettalkohole – eine neue Tensidklasse

Ether Sulfonates Basing on Unsaturated Fatty Alcohols – A New Tenside Type Alkenylpolyglycolalkylethers of the general form R-O-(CH₂-CH₂-O)_n-R′ (R = unsaturated fatty alkyl residue; R′ = alkyl group C₁-C₁₀) lead after sulfonation with a SO₃ air mixture, subsequent neutralization and alkaline pressure hydrolysis to a mixture of ether sulfonates. Sulfonation was carried out in a laboratory fall film reactor and optimized with respect to the SO₃/ ether ratio. Basing on the thus obtained results this reaction could be carried out in a continuous pilot sulfonation plant (through put: 50 kg ether/h). The new ether sulfonates are a very variable tenside type where different properties of application can be chosen in dependence on the ratio of hydrophobic to hydrophilic molecule parts.     

Alpha olefin sulfonates from a commercial SO3-Air reactor

Alpha olefin sulfonate (AOS) can be made by SO₃-air sulfonation of straight chain alpha olefins followed by saponification of the neutralized product. The sulfonation step forms unsaturated sulfonic acids, sultones and sultone sulfonic acids. Hydrolysis of the various sultones yields a mixture of unsaturated and hydroxy sulfonates. Sulfonation of commercial mixtures of straight chain alpha olefins in a large-scale SO₃ falling film unit has given AOS of 1.5–3.0% oil based on active content and tristimulus color of about 40% saturation (2% solution) which is readily bleachable with 1–3% NaOCl to about 10–15% saturation. Performance of AOS made from C₁₅−C₁₈ alpha olefin is comparable to that of the high-foaming C₁₁−C₁₄ LAS in both detergency and dishwashing foam. It is superior to similar products made from internal straight chain olefins. The product shows a low order of toxicity and biodegrad-ability slightly better than that of LAS. A C₁₅−C₁₆ AOS blend is especially attractive in liquid detergent formulations. Presented at the AOCS Meeting, Los Angeles, April 1966.     

Relative rates of sulfonation of linear and branched long-chain alkylbenzenes

Relative rates of sulfonation of a series of 1-phenylalkanes and isomeric branched-chain alkylbenzenes by gaseous SO₃ have been determined. It has been shown that the composition of the mixture undergoing sulfonation has an important bearing on the actual relative rate constant (k _rel) values obtained. This is taken as evidence for the involvement of pyrosulfonic acids as the actual sulfonating species involved in the sulfonation reaction. Consistent k _rel values have been obtained by using an “active solvent” in 10-fold excess as the sulfonating medium. Whereas the branched-chain isomers show very little variation in their rates of sulfonation, the rates of sulfonation of the 1-phenylalkanes increase as the length of the alkyl chain decreases.     

Sulfonated polysulfone

Polysulfone has been sulfonated to varying degrees using a sulfur trioxide–triethyl phosphate complex as the sulfonating agent. These conditions are suitable for surface sulfonation as well as solution sulfonation. The neutralized, sodium salt form is much more stable than the free acid form. The glass transition temperature of polysulfone is increased by as much as 130°C (i.e., to 310°C) by the introduction of ? SO₃Na groups. Sulfonation also causes a major shift in the low-temperature (?100°C) transition of polysulfone. Compositions of intermediate degree of sulfonation, containing 0.5 ? SO₃Na groups per polysulfone repeat unit, are melt processable. This composition also displays the best balance of properties. Water absorption, which exerts a large influence on mechanical properties, ranges from 1% to 61%, depending upon degree of sulfonation and sorption conditions. Water absorption and desorption curves show non-Fickian behavior. Compositions of intermediate degree of sulfonation display optimum reverse osmosis desalination behavior. Gas permeability is significantly reduced by sulfonation. Overall behavior is consistent with an ionomer-type structure.     

A novel method for sulfonation of microporous polystyrene divinyl benzene copolymer using gaseous SO2 in the waste air streams

In this study a novel sulfonation method for microporous polystyrene divinyl benzene copolymer (PSDBP) was introduced. In our sulfonation system gaseous SO₂ is used as the sulfonation agent and planned to be obtained from waste gas streams. The proposed method, therefore, combines SO₂ control and clean sulfonation technology in a single compact design.Molded polymeric monoliths of the PSDBP containing imprisoned H₂O₂ solution inside the pores (PSDBPH₂O₂) were produced in disk shapes. Dry gas mixture containing 3000 ppm SO₂ is fed into PSDBPH₂O₂ disk reactor with a flow rate of 0.8 L/min and effluent gas composition in terms of SO₂ was measured. Breakthrough curves for varied initial H₂O₂ amount were used to calculate SO₂ adsorption capacity and sulfonation degree of the PSDBPH₂O₂ disks.Successful sulfonation of PSDBPH₂O₂ was verified by the changes in its morphological structure and formed sulfone bonds determined by SEM and IR analyses, respectively. Maximum adsorption capacity for PSDBPH₂O₂ for the initial H₂O₂ volume percentage of 13% was determined as 57 mg SO₂/g polymer. It should be noted that SO₂ adsorption was observed only in H₂O₂ imprisoned polymer disks. Sulfonation degree of PSDBPH₂O₂ which attained maximum SO₂ amount is calculated as 10%.     

Sulfonation of solid polystyrene using gaseous sulfur trioxide

Kinetics of the heterogeneous sulfonation of polystyrene (PS) beads using gaseous SO₃ was investigated. Scanning electron microscopy (SEM) and electron diffraction scattering spectroscopy (EDS) was employed to study the kinetics of diffusion of SO₃ into the PS particles. The diffusion of SO₃ through the barrier of sulfonated polystyrene (SPS) on the beads surface was the primary parameter determining the rate and the yield of the sulfonation reaction. The measurement of the time dependence of the thickness of sulfonated layer formed on the solid PS surface provided for the hypothesis that the sulfonation in heterogeneous phase was diffusion controlled. Diffusion coefficients of SO₃ in PS at ?5°C, 22°C, and at 50°C and activation energy of SO₃ diffusion to the solid PS were determined from these experimental data assuming in the first approximation a simple diffusion unaffected by the ongoing sulfonation reaction. The experimental data were fitted using Johanson‐Mehl‐Avrami‐Jerofyeev‐Kolgomorov's equation to obtain an overall rate constant of heterogeneous sulfonation on solid PS surface. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

A modified mixed-acid catalytic system for Beckmann rearrangement of cyclohexanone oxime

ε-Caprolactam (CPL) is mainly produced through Beckmann rearrangement of cyclohexanone oxime catalyzed by oleum in industry nowadays, which suffers the problems like high viscosity and bad mixing, leading to multiple by-products. To this end, a modified mixed-acid catalytic system containing oleum and trifluoroacetic acid (TFA) was proposed to intensify the reaction. The viscosity of the reaction system was studied and the effects of several experimental parameters on the reaction rate and selectivity were also investigated, including oleum/oxime ratio, TFA/oleum ratio, temperature, and SO₃ concentration. Extremely high selectivity (>99.6%) was obtained under all conditions, revealing that by-products in industrial process were mainly formed owing to the insufficient mixing and poor mass and heat transfer rather than experimental parameters. A preliminary mathematical model considering the effect of CPL was developed to predict the reaction rate. These results are helpful to improve the industrial process of CPL production.     

Influence of chemical modification on tribological properties of elastomers

Physical properties of surface modified synthetic elastomers were studied to understand the factors that reduce friction and provide advantages in practical use. Bromination, iodination, sulfonation, and chlorination were investigated. The coefficient of friction μ was measured using a modified version of the pin-on-disc apparatus. The surface energy, morphology, mechanical properties, and extent of chemical modification were also measured. An increased stiffness and microroughness were found to correlate with changes in the coefficient of friction. Sulfonation (100% H₂SO₄) was found to be the most effective and universally acceptable method of chemical treatment from a tribological point of view. © 1995 John Wiley & Sons, Inc.     

Investigations on the side reactions in sulfonation reactions-hydrophobic compounds in the unsulfonated oil fraction

Petroleum ether extracts of alkylbenzene sulfonates prepared by sulfur trioxide, oleum, and sulfuric acid were compared. These extracts contained by-products as well as unreacted material. Dialkylbenzene, originally existing in raw alkylbenzene, resisted against sulfonation, especially when sulfur trioxide was used as sulfonating agent. Sulfone formation seemed to occur in the early stage of sulfonation. Sulfonation with sulfuric acid gave different characteristics to the petroleum ether extract compared with two other means.     

Sulfonated polysulfone as promising membranes for polymer electrolyte fuel cells

A new, milder sulfonation process was used to produce ion‐exchange polymers from a commercial polysulfone (PSU). Membranes obtained from the sulfonated polysulfone are potential substitutes for perfluorosulfonic acid membranes used now in polymer electrolyte fuel cells. Sulfonation levels from 20 to 50% were easily achieved by varying the content of the sulfonating agent and the reaction time. Ion‐exchange capacities from 0.5 to 1.2 mmol SO₃H/g polymer were found via elemental analysis and titration. Proton conductivities between 10⁻⁶ and 10⁻² S cm⁻¹ were measured at room temperature. An increase in intrinsic viscosity with increasing sulfonation degree confirms that the sulfonation process helps to preserve the polymer chain from degradation. Thermal analysis of the sulfonated polysulfone (SPSU) samples reveals higher glass transition temperatures and lower decomposition temperatures with respect to the unsulfonated sample (PSU). Amorphous structures for both PSU and SPSU membranes were detected by X‐ray diffraction analysis and differential scanning calorimetry. Preliminary tests in fuel cells have shown encouraging results in terms of cell performance. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1250–1257, 2000     

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

Fatty 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.     

The chemical transformation of hydrocarbons to carbon using SO3 sources

To develop low-cost carbon fiber, The Dow Chemical Company and others have explored the sulfonation of polyethylene fibers as an alternative to the incumbent poly(acrylonitrile) route. Although the process of polyethylene sulfonation and subsequent thermal carbonization in an inert atmosphere has been known to provide carbonaceous material for over 35 years, we have found the chemical understanding of this transformation to be insufficient. Herein, we report a series of studies that have led to our current understanding for both the sulfonation and subsequent thermal treatment steps. Sulfonation of hydrocarbon model compounds yields completely conjugated and functionalized products. Spectroscopic data suggest that sulfonated polyethylene is similar; containing extended conjugated systems with sulfonic acids and various other oxygen-containing functional groups. Near-Edge X-ray Absorption Fine Structure data have identified that between 150 and 200 °C the polymer undergoes a cross-linking step, while evolved gas analysis has identified concomitant release of SO₂ and H₂O. Above 600 °C, H₂ is produced and a graphenic carbon microstructure is obtained.     

十二烷基二苯醚二磺酸钠的合成

研究了十二烷基二苯醚二磺酸钠阴离子表面活性剂的合成工艺 ,得出烷基化的最佳反应条件为 :催化剂用量为n(反应物 )∶n(催化剂 ) =5∶1;反应时间 5h ;反应温度 70℃ ;二苯醚的转化率 82 %。发烟硫酸磺化的最佳反应条件为 :发烟硫酸的w(游离SO3 ) =15 % ;反应温度 35℃ ;反应时间 1h ;n(反应物 )∶n(发烟硫酸 ) =1∶2 5 ;磺酸基数目为 1 90。氯磺酸磺化的最佳反应条件为 :反应时间 2 0min ;n(反应物 )∶n(氯磺酸 ) =1∶5 ;反应温度 15℃ ;磺酸基数目为 1 92。     

Study of sulfonation mechanism of low‐density polyethylene films with fuming sulfuric acid

Sulfonation of low‐density polyethylene (LDPE) films with fuming sulfuric acid was studied by X‐ray photoelectron spectroscopy (XPS) and attenuated total reflectance (ATR) infrared spectroscopy. The ATR spectra showed the formation of C?C double bonds and multiple sulfur atom containing groups for the sulfonation of LDPE films. This led us to propose that the abstraction reaction of hydride ion by sulfur trioxide (SO₃) in fuming sulfuric acid might account for the formation of the C?C double bonds. It was considered that after the abstraction reaction, these double bonds react with SO₃, resulting in the production of alkene sulfonic acids and sultones, along with the formation of sulfate groups as a result of reaction of the double bonds with sulfuric acid. Experimental data by treatment of the sulfonated LDPE films with KOH and thiourea supported the proposed idea, estimating the approximate molar ratio of the products. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2435–2442, 2004     

Tomography images to analyze the deformation of the cavern in the continuous‐flow mixing of non‐Newtonian fluids

Tomography, an efficient nonintrusive technique, was employed to visualize the flow in continuous‐flow mixing and to measure the cavern volume (V_c) in batch mixing. This study has demonstrated an efficient method for flow visualization in the continuous‐flow mixing of opaque fluids using two‐dimensional (2‐D) and 3‐D tomograms. The main objective of this study was to explore the effects of four inlet‐outlet configurations, fluid rheology (0.5–1.5% xanthan gum concentration), high‐velocity jet (0.317–1.660 m s^?1), and feed flow rate (5.3 × 10^?5?2.36 × 10^?4 m³ s^?1) on the deformation of the cavern. Dynamic tests were also performed to estimate the fully mixed volume (V_{fully mixed}) for the RT, A310, and 3AM impellers in a continuous‐flow mixing system, and it was found that V_{fully mixed} was greater than V_c. Incorporating the findings of this study into the design criteria will minimize the extent of nonideal flows in the continuous‐flow mixing of complex fluids and eventually improve the quality of end‐products. © 2013 American Institute of Chemical Engineers AIChE J, 60: 315–331, 2014     

Sulfonation studies of monoisomeric di- and trialkylbenzenes

Sulfonation studies were conducted on a series of monoisomerically pure di- and trialkylbenzenes in order to determine the regioselectivity of sulfonation and how the selectivity varies with structural changes. Sulfur trioxide, because of its commerical significance, was investigated as the primary sulfonating agent. Lewis base adducts of sulfur trioxide and other sulfonating agents were also investigated for comparison. The studies demonstrated, in a quantitative manner, the tendency of the sulfonation to occur para to alkyl substituents. In one class of the alkylbenzenes investigated, 1,3,4-alkyl dimethylbenzene, the sulfonation which occurred at the position para to the 3-methyl group ranged in selectivity from 87–99%, even though this position, which is ortho to the larger alkyl group, was much less favorable from steric considerations than the position ortho to the 4-methyl group. The determination of the position of sulfonation by a combination of nuclear magnetic resonance and high pressure liquid chromatographic techniques is discussed.     

Beckmann rearrangement of cyclohexanone oxime to ε‐caprolactam in microreactors

Selectivities are presented of the Beckmann rearrangement of cyclohexanone oxime to ε‐caprolactam with oleum for various conditions in three microreactors, viz., Y‐junction, interdigital, and split and recombine mixers, followed by a 50‐cm long microchannel of 250 μm internal diameter. Cyclohexanone oxime is dissolved in cyclooctane, which is inert for oleum. The selectivity is measured in the temperature range of 80–132°C. The concentration range of caprolactam in the reaction mixture is 31–41 wt %, in oleum. The total volumetric flow rate is 0.4 ml/min, whereas the flow rate ratio of ε‐caprolactam/oleum over cyclohexanone oxime/cyclooctane ranges from 0.3 to 3. The selectivities measured with the three microreactors are: 70–99+%, 93–99+%, and 95–99+%, respectively. High ε‐caprolactam concentration (41 wt %), high temperature (110–132°C), and a ratio of free H₂SO₄ to SO₃ of unity have a negative effect on the selectivity. © 2009 American Institute of Chemical Engineers AIChE J, 2010