Sodium Sulfanilate Research Articles

A novel approach for preparing aldehyde-free melamine resin and investigation of its retanning performance

Melamine resin (MR), traditionally synthesized using melamine and formaldehyde, is widely used in the leather industry. However, the emission of free formaldehyde poses a significant challenge for conventional MR. To address the issues of aldehyde in MR, extensive research has been conducted. This paper introduces a novel aldehyde-free MR (LTSL) retanning agent synthesized using cyanuric chloride, l-lysine, and sodium sulfanilate. The chemical structure of LTSL was analyzed via Fourier transform infrared spectroscopy, nuclear magnetic resonance, and X-ray photoelectron spectroscopy. The presence of amino, carboxyl, and sulfonic acid groups in LTSL enhanced its storability and imparted LTSL with an amphoteric character. The isoelectric point of LTSL was optimized to reach 4.37, and LTSL exhibited an appropriate size distribution with an average particle size of 254.17 nm and achieved high absorption rates of 87.77% and 95.84% for retanning and fatliquoring agents, respectively. Consequently, the thickness rate of LTSL reached up to 37%, with no detectable formaldehyde. Notably, LTSL also demonstrated excellent physical and mechanical properties, primarily attributed to the coordination and electrostatic interactions between the chrome-tanned collagen fiber and amino/carboxyl groups in LTSL. This research presents an innovative approach for developing an aldehyde-free MR retanning agent, significantly contributing to the sustainable development of leather manufacturing.Graphical

An Investigation on Optical, Mechanical and Thermophysical Properties of Sodium Sulfanilate Dihydrate Single Crystal for Optical Window And Microelectronics Applications

AbstractA nonlinear optical single crystal of sodium sulfanilate dihydrate (SSDH) is formed using the slow evaporation solution approach. Using X‐ray diffraction, the properties of the unit cell are extracted from a single crystal. Using UV‐Vis‐NIR spectroscopy, the optical transmittance of crystals is determined. Mechanical toughness is evaluated using a Vickers micro hardness test. Sodium sulfanilate dihydrate is synthesized as a single crystal and etched for analysis. Photoacoustic spectroscopy is used to examine the sample's thermal diffusivity. The crystal's thermophysical properties are vital for every element of heat transfer incidences, in addition to being employed in many other applications, including as Nd:YAG lasers, Nd:YLF lasers, acousto‐optics, and microelectronics industry applications.

Visible‐Light Driven Ni‐Incorporated CdS Photocatalytic Activities for Azo‐Bond Cleavages with Hydrogenation Reaction

AbstractNi‐incorporated CdS (Ni‐CdS) photocatalysts with different amounts of Ni dopant have been synthesized, characterized, and examined toward azo‐bond cleavages in visible‐light illuminated conditions. The optimum performance was achieved with a relatively low amount of Ni dopant (2 % atomic mass). The azo bonds of azobenzene (AB) and methyl orange (MO) compounds were hydrogenated with the in‐situ generated hydrogen on Ni‐CdS catalyst surfaces. The hydrogen evolution reaction was proved and measured with GC measurement during the photocatalytic session with an incandescent halogen lamp. Furthermore, the experimental data of UV‐vis spectra analyses suggested the formation of aniline or sodium sulfanilate and p‐aminodimethylaniline with the emerged peaks at ∼240 nm, indicating azo‐bond has been cleaved in AB or MO compounds, respectively. The catalytic performances of 2 % Ni‐CdS are also supported with electrical and photoresponse analyses. To demonstrate the possibility of industrial application, Ni‐CdS catalyst stability is also tested for several runs in reusability experiments and examined with cyclic voltammetry for 100 cycles without any significant degradation. The cleavage mechanisms of azo bonds in AB and MO compounds were discussed and proposed in this work.

Evaluating nitrite content changes in some Chinese home cooking with a newely-developed CDs diazotization spectrophotometry.

The research developed a diazo-coupling carbon-dots (CDs) method for determining nitrite and optimized variables of sodium sulfanilate, CDs synthesis, characteristic wavelength, reaction time and temperature. The method can assay 0.025-2.0mg/L NO2- and has a detection limit of 9.6μg/L and 95-105% recovery. Subsequently, it was applied in detecting NO2- changes in some Chinese home cooking, the gotten results indicated that if the sautéed vegetables (cabbage, Chinese cabbage, spinach and lettuce) and stir-fry pork, fried peas and pickled vegetable are stored at 4°C for 72h, nitrite contents are far lower than the recommended value, but if stored at room temperature for 24h, the content in pure vegetables and shredded pork with green pepper will exceed the recommended value. Therefore, the staying fresher for the sautéed vegetables at room temperature is 24h, if stored in a refrigerator at 4°C, their staying fresher can be extended to 72h.

Optical, dielectric properties and thermal analysis on sodium sulfanilate dihydrate nonlinear optical single crystal

Nonlinear optical sodium sulfanilate dihydrate (SSD) single crystal was grown by slow evaporation solution method at ambient temperature. Unit cell parameters were elucidated with the study of single crystal X-ray diffraction. Fourier transform infrared spectroscopic analyses were performed to indentify a variety of functional groups present in the grown SSD crystal. The level of optical transmittance of the grown SSD crystal was investigated by UV–Vis–NIR spectral analysis. The lower cut off wavelength of the grown crystal was observed at 243 nm and the band gap energy is found to be 5.23 eV. The spectral study of photoluminescence was carried out for the grown crystal which shows a sharp emission peak at 485 nm resulting blue–green emission that is suitable for the optical communication applications. Mechanical strength was measured by utilizing Vickers microhardness test and the value of n is found to be 2.25 asserting that the crystal belongs to soft material category. The dielectric properties were studied as a function of frequency at various temperatures and also the grown SSD crystal has been correlated with electro-optic properties. Thermogravimetric analysis was undertaken by a thermal analyzer with the temperature starting from 30 to 800 °C and TGA/DTA results show that the crystal has good thermal stability and useful for laser applications. Etching analysis also was performed for the grown SSD single crystal proving that it has good crystalline nature with fewer defects.

Study on growth, electronic structure, topological and nonlinear optical properties of semi organic material sodium sulfanilate dehydrate

Sodium sulfanilate dehydrate, organic nonlinear optical single crystals were grown by slow evaporation solution technique. The cell parameters of SSDH were confirmed from single crystal X-ray diffraction analysis. Nonlinear optical activity has been investigated both experimentally and theoretically. Hirshfeld surface analysis of the intermolecular interactions in crystal structures have been used to scrutinize molecular shapes. FT-IR, FT-Raman and UV–visible spectral analysis have been performed. Natural Bond Orbital analysis has been carried out in order to reveal the electronic exchange interaction and charge delocalization of the molecule. For the investigation of nonlinear optical behavior, the electric dipole moment, polarizability and hyperpolarizability computations have been performed using density functional theory.

Sustainable Catalytic Activity of Ag-Coated Chitosan-Capped γ-Fe2O3 Superparamagnetic Binary Nanohybrids (Ag-γ-Fe2O3@CS) for the Reduction of Environmentally Hazardous Dyes-A Kinetic Study of the Operating Mechanism Analyzing Methyl Orange Reduction.

The formation of binary nanohybrids consisting of environmentally benign components, γ-Fe2O3, chitosan (CS), and Ag (Ag-γ-Fe2O3@CS) (CSIOAg), containing very low concentration of Ag NPs (≤1.2 μM), has been reported. In the as-synthesized nanohybrids, the presence of γ-Fe2O3 (8.5 ± 0.8 nm) and Ag (5.9 ± 0.5 nm) are revealed by optical, XRD, TEM, and XPS analyses, and their presence in cubic phase is determined by XRD and SAED measurements. The catalytic activity of CSIOAg has been analyzed by performing the reduction of certain toxic dyes. Under all kinetic conditions, the reaction is attended by an induction period, which is reduced upon increasing [Ag] and [Dye] in a specific concentration range, as well as temperature, suggesting restructuring of the surface prior to reduction. In case of methyl orange (MO), the reduction results in its cleavage to produce N,N-dimethyl-1,4-phenylenediamine and sodium sulfanilate in a significantly higher (>97%) yield in a bimolecular reaction between MO and BH4–. The duration of induction period is regularly decreased and the rate of reduction (kapp) increases linearly with increasing Ag in the wide concentration range (0.03–2.4 μM). The reduction takes place with a second-order rate constant of 2.7 × 104 dm3 mol–1 s–1, which is >3.5-fold higher than that in the absence of chitosan (IOAg) under identical experimental conditions. The kinetics of reduction of MO is controlled by the nature and extent of its adsorption on the catalyst surface. The weaker binding between MO and Ag catalyst only allows its effective reduction. The XPS analysis of CSIOAg and IOAg containing the same amount of Ag (1.2 μM) showed its higher amount on the surface of CSIOAg (0.12%) as compared to that of IOAg (0.09%). Detailed kinetic analysis of MO reduction, performed under pseudo-kinetic conditions for both the nanohybrids revealed them to follow Langmuir–Hinshelwood kinetic model and exhibited the recyclability up to 10 cycles with fairly high reaction efficiency and TOF, suggesting it to be a sustainable green nanosystem.

An Efficient and Green Route to Synthesize Azo Compounds through Methyl Nitrite

A clean preparation of aryl diazonium ions using methyl nitrite is described. Further reaction of the aryl diazonium ions with substituted benzenamine, substituted phenol and nathphol in deferent kinds of diazotization has been developed. In order to improve the water-solubility of the products, azo coupling reactions of sodium sulfanilate hydrochloride diazonium ions were also performed. The procedures are easy operations, environmentally benign conditions and high yields of the products with potential use as azo-dyes and pigments. Furthermore, no nitrous acid is produced during the diazotization which avoided the formation of dark decomposition products of the corresponding aromatic amine. Proposed mechanism is presented according to our procedure.

Synthesis of a novel triazine flame retardant containing sulfur and its application to cotton fabrics

A novel triazine flame retardant (FR) has been successfully synthesized by the reaction of cyanuric chloride with sodium sulfanilate followed by diethanol amine. Its structure has been fully characterized by IR and 1H NMR spectroscopy. The effects of reaction solvent, acid-binding agent, reaction temperature, and molar ratio of starting materials on the yield of FR were investigated in detail. Experiments showed that when the molar ratio of intermediate I to diethanol amine is 1 to 1.2 in the presence of sodium carbonate as acid-binding agent in acetone-water at 45 °C, the yield of the obtained FR reaches 81.4%. Thermogravimetry (TG) test indicated that the FR has good thermostability and char-forming ability. In addition, the flame retardancy and thermal behavior of the cotton fabrics treated with FR were studied by limiting oxygen index (LOI), vertical flammability test, and thermogravimetry (TG) to evaluate the flameretardant performance of the target FR. These results demonstrated that the flame retardancy and thermal stability of the cotton fabrics treated with FR were clearly improved.

Influence of delayed addition time of sodium sulfanilate phenol formaldehyde condensate on the hydration characteristics of sulfate resisting cement pastes containing silica fume

The water–silica fume–cement system is highly sensitive to the effect of superplasticizers. This work aimed to study the individual effects of the dosage and delayed addition time of laboratory synthesized sodium sulfanilate phenol formaldehyde condensate (SSFP) on the hydration characteristics of sulfate resisting cement (SRC) pastes incorporating 10mass% SF and hydrated up to 90days. Initial and final setting times, compressive strength, bulk density, total porosity and hydration kinetics were determined. Some selected specimens were analyzed using IR spectroscopy. The results showed that the fluidity of cement pastes increases with SSFP dosage and delayed addition time up to 10min this is due to the electrostatic repulsion between cement particles and the decrease of C3A content that is minimized by hydration until the dormant period (10–15min). The values of combined water, compressive strength and bulk density increase with polymer content up to 1.5mass% with delayed addition time up to 10min; this is intrinsically associated with the reduction of W/C ratio with polymer content as well as the improvement of superplasticizing effect of SSFP with delayed addition. IR spectra are in a good agreement with the results of physico-chemical and mechanical properties. The synthesized SSFP condensate could improve the fluidity, bulk density and compressive strength of the investigated cement pastes.

Synthesis of Lignin-Modified Sulfanilate-Phenol-Formaldehyde Condensate and Application as Concrete Superplasticizer

Modified sulfanilate-phenol-formaldehyde condensate (MSPF) was synthesized by a reaction among soda lignin, sodium sulfanilate, phenol and formaldehyde. Optimal conditions of synthesis were obtained by studying the effects of raw material consumptions and reaction time on the dispersive property of products. Evaluation the applying performance of MSPF indicated that this new superplasticizer has an excellent water-reducing effect, and it can improve the compressive strength of hardened concrete obviously, especially the latter compressive strength. Most important of all, MSPF not only inherits the slump-maintaining capacity of aminosulfonate-based superplasticizer, but also overcomes the shortcoming of bleeding by improving the water retention capacity and reduces the segregation of mortar or concrete. Results show that MSPF is a potential superplasticizer for the high-strength and high-performance concrete.

Synthesis, Characterization, and Application Properties of Aminosulfonate-Phenol-Salicylic Acid-Formaldehyde (AH) Polymer in Concrete

AbstractIn this study, a water-soluble aminosulfonate-phenol-salicylic acid-formaldehyde (AH) polymer was synthesized by the reaction between phenol, sodium sulfanilate, salicylic acid, and formaldehyde; the molecular structure of synthesized AH polymer under the optimum reaction conditions was characterized by Gel permeation chromatography (GPC) and infrared spectroscopy (IR); and the effect of AH polymer on the application properties of concrete, i.e., water reduction percentage, slump preservation, air content, wet density, setting times, the compressive strength, and the flexural strength, was compared with aminosulfonate-phenol-formaldehyde (AS) polymer. The test results indicated that the molecular weight of AH polymer has a narrower range distribution and a new function group (−COOH) was bonded to the main chain of AH polymer molecule, the use of AH polymer in concrete resulted in an increase of the air content of concrete and a decrease of the wet density of fresh concrete, concrete with AH polyme...

Sodium sulfanilate dihydrate (SSDH) single crystals grown by conventional slow evaporation and Sankaranarayanan–Ramasamy (SR) method and its comparative characterization analysis

A transparent uniaxial sodium sulfanilate dihydrate (SSDH) single crystal having dimension of 30mm diameter and 100mm length was grown by Sankaranarayanan–Ramasamy (SR) method with a growth rate of 1mm per day. Using an identical solution the conventional crystal grown to a dimension of 12mm×20mm×5mm was obtained over a period of 20 days. The crystal structure has been confirmed by single crystal X-ray diffraction (XRD) measurement. The crystalline perfection of sodium sulfanilate dihydrate crystals grown by slow evaporation solution technique (SEST) and SR method were characterized using chemical etching, laser damage threshold, Vickers microhardness, UV–vis NIR, birefringence and dielectric analysis. The above study indicates that the crystal quality of the Sankaranarayanan–Ramasamy (SR) method grown sodium sulfanilate dihydrate is good compared to conventional solution method grown SSDH crystal. The growth features of inclusions, low angle grain boundaries, twins and micro-cracks have been observed in conventional method grown SSDH crystals. The dielectric tensor components for unidirectional method grown sodium sulfanilate dihydrate single crystal were evaluated as a function of temperature at 100Hz frequency.

Kinetics and Mechanism of Oxidation of Sodium Sulfanilate by Dihydroxydiperiodat Onickelate(IV) in Aqueous Medium

The kinetics of oxidation of sodium sulfanilate by dihydroxydiperiodatonickelate?IV?(DPN) was studiedspectrophotometrically in alkaline medium. The reaction rate showed first order dependence in oxidant andfractional order in reductant. The corresponding reaction mechanism involving a pre-equilibrium of adductformation between the complex and reductant was proposed. The rate equations derived from mechanism canexplain all experimental observations. The activation parameters along with rate constants of the rate-determiningstep were calculated.

Growth and characterization of sodium sulfanilate dihydrate (SSDH) crystals for NLO applications

The organic nonlinear optical crystal of sodium sulfanilate dihydrate (SSDH) was grown by slow cooling solution growth technique using water as solvent. Single-crystal X-ray diffraction and Fourier transform infrared (FTIR) spectral analyses were used to confirm the SSDH crystals. The UV–visible and photoluminescence studies were carried out. The second-harmonic generation of SSDH was tested by Kurtz–Perry powder technique. The hardness and laser damage threshold on the (0 0 1) and (0 1 0) planes were analyzed.

Kinetics of reverse osmosis desalination of aqueous sodium sulfanilate

Kinetics of reverse osmosis desalination of aqueous sodium sulfanilate is studied on a laboratory pressure filter unit, in relation to the solution concentration, temperature, and pressure in the intermembrane channel.

Green and efficient diazotization and diazo coupling reactions on clays

Diazotization and diazo coupling reactions of sodium sulfanilate dihydrate and para-diazonium benzene sulfonyl azide with aromatic phenols over eco-friendly clay catalysts are described. These inexpensive, noncorrosive and reusable catalysts were found to exhibit bifunctional catalytic properties for diazotization and diazo coupling reactions. No considerable decreases in the efficiency of the catalysts were observed after four cycles of operation. The new method totally avoids the use of acids, alkalies and toxic solvents in diazotization and diazo coupling reactions.

Kinetics of reductive degradation of Orange II in aqueous solution by zero‐valent iron

AbstractThe reductive degradation of Orange II in aqueous solution by zero‐valent iron was investigated. The degradation of Orange II followed pseudo‐first‐order kinetics at various pH values and initial Orange II levels, but the formation of sodium sulfanilate, a major reductive product of Orange II, followed zero‐order kinetics. Copyright © 2004 Society of Chemical Industry

Highly sensitive and selective methods for identifying and determining copper(II) with N-phenyl-N′-sodium sulfanilate thiourea

Highly sensitive and selective methods for identifying and determining copper(II) with N-phenyl-N′-sodium sulfanilate thiourea

Hydrosilation Reactions Catalyzed by Supported Bimetallic Colloids

The preparation and catalytic properties of bimetallic colloids consisting of a ligand-stabilized Pt shell on Au or Pd cores supported by alumina are described. The aim of this work is to study the influence of the electronegativity of the colloidal core metals on the activity and selectivity of the surface Pt in hydrosilation reactions. Au is more electronegative and Pd is more electropositive than Pt. Results are compared to controls in which the hydrosilation reaction is catalyzed by colloids made of pure Pt which are also stabilized with the same ligands and supported by alumina. The reaction of HMTS with 1-octene to form bis(trimethylsiloxy)octamethylsilane (BTOMS) was selected to serve as an example of a typical hydrosilation reaction. The synthesis of the bimetallic colloids was accomplished by the seed-growth mechanism. The inner core consisting of Au (diameter = 18 nm) or Pd (diameter = 20 nm) was generated by the reduction of HAuCl4 or H2PdCl4, respectively, by sodium citrate. The Pt outer shell was then grown on the core metals by the reduction of H2PtCl6 with hydroxylammonium chloride. The thickness of the Pt shell depended on the molar concentration of H2PtCl6. Colloidal Pt of undefined morphology is used in industrial processes which require temperatures as high as 120 °C and a 25% excess of the olefin in order to obtain quantitative yields of BTOMS. The hydrosilation process however became more efficient if Pt colloids of 9 nm diameter (Pt9) or bimetallic Au/Pt18/27 colloids (diameter Au core = 18 nm, thickness of Pt shell = 4.5 nm) were used. The first number indicates the diameter of the inner core metal and the second number indicates the total diameter of the bimetallic particle. Both types of colloids were stabilized by p-H2NC6H4SO3Na (sodium sulfanilate) ligands. These colloid catalysts operated best at 60 °C and without a need for excess 1-octene. The yield of BTOMS is 92−93% after 24 h reaction time. The hydrosilation process was improved remarkably if bimetallic colloids made of Pd/Pt20/27 catalysts are used. A BTOMS yield of 90% was reached after only 4−6 h and became greater than 96% after a 24 h reaction period. In addition, ca. 1% of byproducts were formed and only 0.2% of the HMTS was left unreacted. Lifetime testing of the heterogenized colloids, especially of the optimal Pd/Pt system, indicated that catalytic activity was constant over at least six cycles. The results presented in this paper clearly prove that catalysts consisting of layered metals also demonstrate significantly enhanced activity resulting from mutual interaction of the component metals.