硫酸盐型孪连表面活性剂及其复配体系的泡沫性能

采用动态泡沫扫描法研究了双直链烷基硫酸盐型孪连表面活性剂水溶液的泡沫性能,并考察了添加氯化钠和疏水缔合水溶性聚丙烯酰胺(HMPAM)后对其泡沫性能的影响。结果表明,此系列孪连表面活性剂具有良好的泡沫性能;随着联接基长度的增加,表面活性剂的起泡能力略有降低,泡沫的稳定性能却明显下降;随着温度升高,泡沫半衰期显著降低;无机盐的加入使表面活性剂的起泡能力减弱,而泡沫稳定性随无机盐浓度的增加先升高后降低;HMPAM的加入明显增强了泡沫稳定性。     

次氯酸钠溶液稳定性研究

研究了次氯酸钠水溶液的稳定性,考察了温度、pH值、金属离子种类和浓度、表面活性剂等对次氯酸钠溶液稳定性的影响。结果表明,在温度低于25℃、pH大于12．6时,次氯酸钠溶液稳定性较好,溶液中Ca^2 、Mg^2 离子的存在对次氯酸钠溶液稳定性影响不大;而Fe^2 、Mn^2 离子的存在会促进其分解;表面活性剂硅酸钠可作为次氯酸钠消毒液的良好添加剂。     

Investigation of lithium transport through LiMn2O4 film electrode in aqueous LiNO3 solution

Lithium transport through LiMn₂O₄ film electrode was investigated in aqueous saturated LiNO₃ solution by analyses of the potentiostatic current transient and ac-impedance spectra. It was found that the current transient hardly shows the Cottrell behaviour, and the initial current is linearly proportional to the potential step. This strongly suggests that lithium transport through the film electrode proceeds in aqueous LiNO₃ solution by the same mechanism involving the cell-impedance-controlled constraint, as does lithium transport in non-aqueous organic solution such as LiClO₄ in propylene carbonate (PC). However, the cell-impedance in aqueous LiNO₃ solution was determined to be much smaller by more than one order in value than that cell-impedance in non-aqueous LiClO₄-PC solution over the whole potential range, indicating lithium transport is markedly enhanced in aqueous electrolyte. From the comparison between the ac-impedance spectra obtained in aqueous and non-aqueous electrolytes, the reduced cell-impedance in aqueous electrolyte can be accounted for by the kinetic facility for the interfacial charge-transfer reaction in the absence of the resistive surface film as well as by the high conductivity of the electrolyte itself.     

次氯酸钠水溶液稳定性及增稠体系研究

研究了温度、pH值、金属离子和表面活性剂对次氯酸钠水溶液稳定性的影响。在 2 5℃以下 ,pH >12 4时次氯酸钠溶液较稳定 ;金属离子的存在促进其分解。并找到了能够在次氯酸钠中稳定存在的表面活性剂WC 2A1(十二烷基二苯醚二磺酸钠 )。同时对有效氯含量、非离子表面活性剂 (GMY)及阴离子表面活性剂 (L - 30 )、pH值对次氯酸钠水溶液黏度的影响作了研究 ,得出了所需黏度的配方 :w(GMY) =7%～ 8% ,w(L - 30 ) =2 %～ 3%。     

AES在草铵膦水剂中的应用研究

将阴离子表面活性剂脂肪醇聚氧乙烯醚硫酸钠(AES)添加到草铵膦水溶液中,考察了配制得到的草铵膦制剂的低温和热贮稳定性,并对其表面张力、渗透力和药效等性能进行测定。实验发现,当配方组成为草铵膦母药20%、AES 20%时,制剂的低温和热贮稳定性符合水剂的质量技术指标,表面张力大大降低,渗透力大大提高,且对牛筋草和空心莲子草有较高的生物活性。     

Electrochemical degradation of anionic surfactants

This study was performed to investigate the electrochemical oxidation of anionic surfactants. In particular, a synthetic solution of sodium dodecyl benzene sulfonate and a real car wash wastewater were treated by galvanostatic electrolysis using a Ti–Ru–Sn ternary oxide and a boron-doped diamond (BDD) anode. Measurements of the Chemical Oxygen Demand (COD) and the concentration of the anionic surfactants were used to follow the oxidation. Using the Ti–Ru–Sn ternary oxide anode, the complete removal of COD and sodium dodecyl benzene sulfonate was obtained only in the presence of chloride ions that act as inorganic mediators. The oxidation rate was almost independent of current density and electrolyte flow rate. In the case of BDD the mineralisation of the sodium dodecyl benzene sulfonate was achieved in all experimental conditions due to reaction with hydroxyl radicals electrogenerated on the diamond surface during electrolysis. The COD removal rate increased with increase in electrolyte flow rate, indicating that the oxidation was mass-transfer controlled. Comparison of the results of the two electrodes showed that chlorine mediated oxidation at the Ti–Ru–Sn ternary oxide anode allowed a faster COD removal of both the synthetic solution and real car wash wastewater.     

Electrochemical properties of supercapacitors operating in aqueous electrolyte with surfactants

Effect of surfactants present in alkaline and acidic solutions on the capacitance of carbon electrodes has been studied. Three various types of surfactants, i.e. sodium dodecyl sulphate (SDS), tetrapropylammonium bromide (TPAB) and non-ionic such as polymer of polyethylene glycol and p-t-octylophenol (Triton X-100) have been selected for this target. Concentration of these electrolyte additives was 0.005 mol L⁻¹. Decreasing the surface tension in the electrode/electrolyte interface allows better penetration of electrolyte into the pores. However, surfactants played a different role depending on the electrode polarity. Detailed analysis of capacitance versus current load, frequency dependence as well as self-discharge and cyclability proved especially a profitable effect of Triton X-100 on capacitor operating in alkaline solution.     

Synthesis,Characterization, and Surface-Active Properties of Carboxylbetaine and Sulfobetaine Surfactants based on Vegetable Oil

A novel series of carboxylbetaine-type and sulfobetaine-type zwitterionic surfactants (castor oil amidoethyl betaine, castor oil amidoethyl sulfobetaine [CAAS], cottonseed oil amidoethyl betaine, and cottonseed oil amidoethyl sulfobetaine [COAS]) were synthesized via the reactions of nonedible vegetable oils (castor oil and cottonseed oil) with dimethylaminoethylamine, followed by the reaction with sodium chloroacetate and sodium 2-hydroxy-3-chloropropane sulfonate, respectively. Their chemical structures were confirmed using the electrospray ionization mass spectrum (ESI-MS) and infrared (IR) spectra. The surface activities of the prepared compounds were measured by surface tension. It was noticed that the sulfobetaine-type surfactants in aqueous solution performed slightly better at reducing surface tension than the carboxylbetaine-type surfactants. Meanwhile, the synthesized surfactants possess a broad range of isoelectric points, superior foam properties, and exhibit some antibacterial activity on Gram-positive and Gram-negative bacteria.     

Effect of Inorganic Additives on a Conventional Anionic–Nonionic Mixed Surfactants System in Aqueous Solution

The interaction between an anionic surfactant (sodium dodecyl sulfate) and a nonionic surfactant [polyoxyethylene (9.5) octyl phenyl ether] in aqueous salt solution was investigated using the surface tension method. The critical micelle concentration values were determined for the individual surfactants and their corresponding mixtures. The interaction parameter between the surfactants in the mixed micelles, the activity and activity coefficients in the mixed micelles, and the thermodynamic parameters were calculated using various approaches, viz., Clint, Rubingh, and Maeda models. It was observed that the critical micelle concentration of the mixed surfactants system reveals little deviation from ideality.     

Wetting Behavior of Aqueous Solutions of Binary Surfactant Mixtures to Poly(tetrafluoroethylene)

Measurements of the surface tension (γ _LV) and advancing contact angle () on poly(tetrafluoroethylene) (PTFE) were carried out for aqueous solutions of cetyltrimethylammonium bromide (CTAB), cetylpyridynium bromide (CPyB), sodium decylsulfate (SDS), sodium dodecylsulfate (SDDS), p-(1,1,3,3-tetramethylbutyl) phenoxypoly(ethylene glycol)s, Triton X-100 (TX100) and Triton X-165 (TX165) and their mixtures. The results obtained indicate that the values of the surface tension and wettability of PTFE depend on the concentration and composition of the surfactants mixture. In contrast to Zisman finding, there was no linear dependence between cos and the surface tension of aqueous solutions of surfactants and their mixtures for all studied systems, but a linear dependence existed between the adhesional tension and solution surface tension for PTFE in the whole concentration range, the slope of which was –1, indicating that the surface excess concentration of surfactant at the PTFE–solution interface was the same as that at the solution–air interface for a given bulk concentration. It was also found that the work of adhesion of aqueous solutions of surfactants and their mixtures to PTFE surface did not depend on the type of surfactant, its concentration and composition of the mixture. This means that for the studied systems the interaction across PTFE–solution interface was constant, and it was largely of Lifshitz–van der Waals type. On the basis of the surface tension of PTFE and the Young equation and thermodynamic analysis of the work of adhesion of aqueous solutions of surfactants to the polymer surface it was found that in the case of PTFE the changes of the contact angle as a function of the total mixture concentration in the bulk phase resulted only from changes of the polar component of the solution surface tension.     

Surface adsorption in the mixtures of sodium dodecylsulphate and oxyethylenated nonylphenol with different oxyethylenation degrees

The effectiveness of surface adsorption in an aqueous solution of mixtures of surfactants composed of an anionic surfactant, sodium dodecylsulphate, mixed with a nonionic one, polyoxyethylenated nonylphenol, was studied. Their behavior was compared separately. This surface adsorption was characterized by the values of the surface tension at 25°C of the total concentrations below, but near to the critical micelle concentration (CMC) in the mixtures mentioned. These were obtained as a function of different proportions of surfactants in the mixture and different chain lengths of nonionic polyoxyethylenated surfactant. The total surface excess concentrations of the surfactant mixtures and the average of molecular area per surfactant species at the aqueous solution/air interface were calculated. Finally, the values were analyzed vs the above parameters. Presented at the XDCth Meetings of CED/AID, Granada, Spain, March, 1988.     

磺基咪唑啉甜菜碱表面活性剂的合成和性能

以２－溴乙基磺酸钠为亲水基物料和烷基咪唑啉合成了磺基咪唑啉甜菜碱表面活性剂,讨论了该化合物在水中的结构,并对其水溶液的表面张力、起泡性能、临界胶束浓度进行了测试和分析。     

Recovery of Phenols Using Liquid Surfactant Membranes Prepared with Newly Synthesized Surfactants

Abstract

Extraction and stripping equilibrium of phenol, p-cresol, and p-chlorophenol were studied with an organic solution containing a newly synthesized surfactant and an aqueous alkaline solution as a stripping phase. A cationic surfactant showed the highest extraction ratio of phenol among several surfactants used in this study. The magnitude of phenol extracted from water was in the order phenol < p- chlorophenol < p-cresol. The stripping of phenol extracted in the organic solution was quantitatively accomplished with an alkaline solution of high concentration except for the case of cationic surfactants. Extraction of phenol and its derivatives by liquid surfactant membranes containing a newly synthesized surfactant as an emulsifier was carried out in a stirred cell. The effects of various parameters (such as a surfactant and alkaline concentration, the kind of surfactant, and the alkali composition) on the extraction efficiency of phenol were examined along with demulsification of W/O emulsions. On the basis of the stability of surfactants against alkaline solutions used as a receiving phase, cationic surfactants which did not involve an ester or amide bond in their molecule appeared to be among the best surfactants available for phenol removal in liquid membrane operations. The efficiency of phenol recovery with sodium hydroxide as a stripping agent was much higher than that with sodium carbonate; however, the demulsification efficiency of the emulsions decreased with an increase in the content of sodium hydroxide in the mixed alkaline solutions of sodium hydroxide and sodium carbonate. In the design of an efficient recovery process of phenols by LSMs, the composition of the alkaline solution was one of the key factors. Under optimal conditions, phenolic derivatives could be recovered in a few minutes.

     

Methods for Determining the Marangoni Numbers in Studying the Absorption in the Operation of a Heat Pump

It is analyzed whether or not experimental data on the surface tension of an aqueous lithium bromide solution with or without surfactants can be used to study the heat and mass transfer in the operation of the absorber of a heat pump. Examples of the erroneous determination of the Marangoni numbers under these conditions are given. A method for calculating the interfacial tension gradients and the Marangoni numbers is proposed. It is argued that it is necessary to perform additional experimental investigations for determining the interfacial tension under the conditions of equilibrium in the surfactant-containing aqueous lithium bromide solution-water vapor system at constant water vapor pressure.     

The interaction between co-polymer of vinylpyrrolidone and vinylacetate and anionic surfactants in aqueous solutions

The interaction of co-polymers of vinylpyrrolidone-vinylacetate with anionic surfactants, such as lithium dodecyl sulfate (LiDS), lithium perfluorooctane sulfonate (LiFOS) in aqueous solution, has been studied. When the content of vinylacetate in the co-polymers increases, reduction in the surface tension of co-polymers alone becomes significant. In mixtures of co-polymers and surfactants, co-polymer-LiFOS complexes are formed at lower surfactant concentration than that of co-polymer-LiDS. The micropolarity of the co-polymers-surfactant complexes depends on the composition of co-polymers and is higher for co-polymer-LiFOS than that for co-polymer-LiDS. Further, the solubilization behavior of α-(o-tolylazo-)-β-naphthylamine (Yellow OB) (Tokyo Kasei Co., Ltd., Tokyo, Japan) in the co-polymer-surfactant complexes is almost independent of the co-polymer composition, but different from the surfactants, where a very low solubilized amount of Yellow OB is observed for co-polymer-LiFOS.     

碳酸锂在碳酸钠溶液中的溶解度与热力学

采用等温溶解平衡法开展碳酸锂在碳酸钠溶液中(278.15～358.15 K)的溶解平衡实验研究,测定平衡体系碳酸锂溶解度和平衡溶液密度,利用E-DH方程对碳酸锂溶解度实验数据进行关联,标准偏差小于0.01;利用Connaughton方程对液相密度数据进行关联,标准偏差小于2×10^-3。实验和计算研究结果表明：在同离子和盐效应协同影响下,碳酸锂在Na₂CO₃-H₂O体系中溶解度随碳酸钠浓度增加先降低后降低趋势变缓,在278.15～358.15 K温度范围内,溶解度转变折点为碳酸钠浓度约为0.1 mol·kg^-1;通过溶解热力学计算,得到碳酸锂在碳酸钠中的溶解焓变(ΔH_d)、熵变(ΔS_d)和Gibbs自由能变(ΔG_d),结果表明溶解过程为放热、熵减的非自发过程,溶解焓变和熵变随着碳酸钠浓度增加而增加,Gibbs自由能变在0.6 mol·kg^-1出现最大值,且溶解过程为熵控制过程。研究结果将为卤水提锂碳化沉锂过程设计提供基础数据。     

Rapid Room Temperature Synthesis of Hexagonal Mesoporous Silica Using Inorganic Silicate Sources and Cationic Surfactants under Highly Acidic Conditions

The room-temperature synthesis of mesoporous silica was investigated by using cationic surfactants and inorganic Si sources, like sodium silicate and colloidal silica. Mesoporous silica analogous to the hexagonal MCM-41 could be obtained over a wide range of pH below ca. 11 within short synthesis time (3 h), when the Q⁴-state Si was absent in the Si source solution prior to mixing with an aqueous solution of cationic surfactants. It was suggested that the strongly acidic conditions (pH < 1) were favorable to give mesoporous silica materials with higher surface area and larger mesopore volume.     

Characteristics of an aqueous rechargeable lithium battery (ARLB)

Electrochemical performance of an aqueous rechargeable lithium battery (ARLB) containing a LiV₃O₈ (negative electrode) and LiCoO₂ (positive electrode) in saturated LiNO₃ aqueous electrolyte was studied. These two electrode materials are stable in the aqueous solution and intercalation/deintercalation of lithium ions occurs within the window of electrochemical stability of water. The obtained capacity of this cell system is about 55 mAh/g based on the mass of the positive electrode, which is lower than the corresponding one in the non-aqueous lithium ion battery. However, its specific capacity can be compared with those of the lead acid and Ni-Cd batteries. In addition, initial results show that this cell system is good in cycling.     

Electrochemical behavior of LiCoO2 in a saturated aqueous Li2SO4 solution

The electrochemical behavior of a commercial LiCoO₂ with spherical shape in a saturated Li₂SO₄ aqueous solution was investigated with cyclic voltammetry and electrochemical impedance spectroscopy. Three redox couples at E_SCE = 0.87/0.71, 0.95/0.90 and 1.06/1.01 V corresponding to those found at ELi/Li⁺=4.08/3.83, 4.13/4.03 and 4.21/4.14 V in organic electrolyte solutions were observed. The diffusion coefficient of lithium ions is 1.649 × 10⁻¹⁰ cm² s⁻¹, close to the value in organic electrolyte solutions. The results indicate that the intercalation and deintercalation behavior of lithium ions in the Li₂SO₄ solution is similar to that in the organic electrolyte solutions. However, due to the higher ionic conductivity of the aqueous solution, current response and reversibility of redox behavior in the aqueous solution are better than in the organic electrolyte solutions, suggesting that the aqueous solution is favorable for high rate capability. The charge transfer resistance, the exchange current and the capacitance of the double layer vary with the charge voltage during the deintercalation process. At the peak of the oxidation (0.87 V), the charge transfer resistance is the lowest. These fundamental results provide a good base for exploring new safe power sources for large scale energy storage.     

表面活性剂对孪尾缔合聚合物水溶液表观黏度的影响

用黏度法研究了孪尾疏水缔合水溶性聚合物聚（丙烯酰胺／丙烯酸钠／N,N-二己基丙烯酰胺）[P（AM／NaAA／DiC6AM）]与十二烷基硫酸钠（SDS）、十六烷基三甲基溴化铵（CRAB）、OP-10的相互作用。结果表明,水溶液的表观黏度随SDS、CTAB质量浓度的增加急剧上升,超过一定浓度后水溶液黏度又急剧下降;黏度上升的幅度随疏水单体用量的增加、表面活性剂与疏水单体的摩尔比率（SMR值）的减小而增大;随水解度的增加,黏度上升的幅度较小。P（AM／NaAA／DiC6AM）的临界缔合浓度cac约为30g/mL,当加入SDS、CTAB时,能显著地降低。随OP-10质量浓度的增加,水溶液表观黏度几乎不变。表明P（AM／NaAA／DRAM）与SDS、CTAB的疏水缔合作用较强,而与OP-10的疏水缔合作用较弱。