首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Synthesis and properties of sulfated alkanolamides   总被引:2,自引:0,他引:2  
High purity alkanolamides were prepared by the sodium catalyzed reaction of methyl stearate, methyl palmitate and methyl laurate with ethanolamine, 2-hydroxypropylamine, 3-hydroxypropylamine and N-methyl N-hydroxyethylamine. The effect of structure on the surface active properties of the sulfation products was investigated. Stability studies showed that sulfated N-methyl N-hydroxyethylstearamide hydrolyzed rapidly by first order kinetics in acid or base. Sulfated hydroxyalkyl primary amides hydrolyzed slower in basic media following second order kinetics. Methyl groups attached to the N atom or to C in the short aliphatic chain improved solubility but had little effect on critical micelle concentration. The alkanolamides of palmitic and stearic acids were good detergents and lime soap dispersing agents. Presented at the AOCS Meeting in Minneapolis, Minn., October 1969. E. Utiliz. Res. Dev. Div., ARS, USDA  相似文献   

2.
Sulfated alkanolamides of hydrogenated tallow fatty acids have been shown to possess excellent lime soap dispersing and detergent properties. However the high melting points of the alkanolamides and their relative insolubility in organic solvents such as dichloroethane make sulfation on an industrial scale awk ward. This difficulty has been overcome by the use of a eutectic mixture of the N-(2-hydroxypropyl)amide and N-(2-[2-hydroxyethoxy]ethyl)amide of unhydrogenated tallow fatty acids. The sulfation of such a mixture can be carried out at or slightly above room temperature, and only a small amount of a chlorinated solvent is required in order to keep the sulfation mixture fluid. The resulting sulfated mixed alkanolamide is an excellent lime soap dispersing agent, which is formulated readily with tallow soap and a glassy silicate into an effective heavy duty detergent.  相似文献   

3.
Nine anionic detergents from five general classes (alcohol sulfates, ether alcohol sulfates, sulfated alkanolamides, α-sulfo esters and alkylbenzenesul-fonates) were rapidly screened for biodegradability under aerobic and microaerophilic conditions in river water at 25 and 35 C. In decreasing order, the ease of biodegradation under microaerophilic conditions at 35 C was as follows: alcohol sulfates, sulfated alkanolamides, α-sulfo fatty acid esters and ether alcohol sulfates. Linear alkylbenzenesulfonate did not degrade. Presented at the AOCS Meeting, New Orleans, April 1970.  相似文献   

4.
Fractions of cyclic fatty acid monomers (CFAM) were isolated from linseed oil heated at 275°C for 12 hr under nitrogen, at 240°C for 10 hr under nitrogen and at 240°C for 10 hr under air. Cyclic fatty acid monomers fractions were also isolated from a sunflower oil heated at 275°C for 12 hr under nitrogen and at 200°C for 48 hr in a commercial fryer. The CFAM fractions were hydrogenated and their composition studied by gas liquid chromatography coupled with mass spectrometry (GC-MS). The CFAM in the fraction isolated from heated linseed oil samples were a mixture (1:1) ofcis andtrans cyclopentyl and cyclohexyl isomers, while the CFAM in the fractions isolated from heated sunflower oils were mostly cyclopentyl isomers. The major cyclopentyl isomers weretrans andcis methyl 7-(2′-hexylcyclopentyl) -heptanoate, methyl 9-(2′-butyl-cyclopentyl)-nonanoate and methyl 10-(2′-propylcyclo-pentyl)-decanoate. The major cyclohexyl isomers were thetrans andcis methyl 9-(2′-propylcyclohexyl)-nonanoate which represented about 50% of the CFAM isomers isolated from heated linseed oil samples. For part II in this series see Ref. 1.  相似文献   

5.
合成了以SN1为代表的脂肪酸烷基醇酰胺硫酸酯烷醇胺盐.并以SN1为例对合成工艺、与月挂酸钠的复配体系进行了研究。  相似文献   

6.
Four soybean oils (SBO) with different fatty acid (FA) compositions were tested for stability during intermittent heating and frying of bread cubes. None of the oils was hydrogenated or contained any additives. Two of the oils were from common commercial varieties. The other two oils were from seed developed in a mutation breeding program and included the line A5, which contained 3.5% linolenate, and the line A6, which contained 20% stearate. Each oil (450 g) was heated to 185 C in a minifryer. Bread cubes were fried at the beginning of heating, and half were stored at −10 C to preserve freshness. The second half was stored at 60 C for 14 days. Heating was continued for 10 hr/day for four days. After 40 hr of heating, an additional 30 g of bread cubes were fried. According to sensory evaluations of the fried bread cubes, peroxide values of oil extracted from the cubes and conjugated diene values of the oils, the A5 and A6 oils were more stable than those from the commercial varieties. Small differences occurred in the flavor and oxidative stability of the cubes fried after 40 hr of heating the oils. Large differences between A5 and A6 and the commercial varieties occurred after storage of bread cubes for 14 days.  相似文献   

7.
Silk fibroin (Bombyx mori) was sulfated with an aqueous sulfuric acid solution. The sulfated fibroin was characterized by Fourier transform infrared spectroscopy (FTIR), amino acid analysis, and gel filtration chromatography (GFC). Maximum yield was obtained at around 2–4 h, and it decreased at 6 h and more. The molecular size decreased and dispersed with sulfation, and the molecular weight was estimated at around 10,000 by GFC using protein standards. The amino acid composition indicated that the crystal region of the fibroin molecule remained in sulfated fibroin until a sulfation reaction time of 4 h. The incorporation of sulfate groups was confirmed by FTIR and the amount of sulfate groups introduced for 4 h sulfation was estimated in 0.3 mmol/g by acidimetric titration. The efficiency of sulfation was calculated at 15.7%. Blood coagulation was prevented by 20 mg of sulfated fibroin in 1 mL of blood, while original fibroin did not show the effect. This result indicates that sulfate group introduction results in addition of anticoagulant function to silk fibroin. Although a variety of polymer backbones have been used for synthesis of sulfated polymers as anticoagulant materials, no reports are available concerning a sulfated polymer based on a protein backbone. Sulfated fibroin is a new type of anticoagulant material having a protein backbone. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2377–2382, 2003  相似文献   

8.
A low-temperature synthesis of fatty alkanolamides, fatty diamides and fatty aralkylamides directly from triglycerides and primary amines provides essentially quantitative yields of the various products. The reactions run to completion in 3–12 h at temperatures of 50–60°C, approximately 100°C lower than employed in present conventional practice. The amines are used in excess and serve as solvent, reagent and, perhaps, as catalyst. The amides were characterized by melting point and spectroscopic (infrared and nuclear magnetic resonance) methods. If the mixed amides produced from the various natural triglyceride mixtures of fats and oils are acceptable products, this synthetic method provides these products in satisfactory quality while conserving energy and avoiding the intermediate production of free fatty acids or their esters.  相似文献   

9.
Heat treatment of rapeseed (primor) and soybean oils resulted in the geometrical isomerization of linolenic acid. The geometrical isomers were isolated from a rapeseed oil heated at 240 C for 10 hr by a combination of thin layer chromatography (TLC) of the methoxy bromomercuric adducts of the total methyl esters and AgNO3-TLC. Three major isomers were identified after hydrazine reduction followed by ozonolysis in BF3-MeOH as 18:3Δ9c, 12c, 15t, 18:3Δ9t, 12c, 15c and 18:3Δ9t, 12c, 15t. These were accompanied by minor amounts of 18:3Δ9c, 12t, 15c, 18:3Δ9c, 12t, 15t and 18:3Δ9t, 12t, 15c. The 18:3 isomers were detected in both soybean and rapeseed oil heated at 240 C for 10 hr. At this temperature, the increase in time of the heat treatment from 10 to 40 hr resulted in a relative increase of the di-trans and in a decrease of the mono-trans isomers. Only minor quantities of these isomers were detected in the oils heated at 200 C for 10 hr. At this temperature, the increase in time of the heat treatment resulted in an increase of both the mono- and di-trans isomers. Presented in part at the I.S.F. Congress, October 1983, Budapest, Hungary.  相似文献   

10.
The effect of sulfate on the crystal structure of zirconia   总被引:1,自引:0,他引:1  
Zirconia can be prepared to produce either tetragonal phase or predominantly monoclinic phase upon calcination at 500 °C. The precursors for each phase of zirconias was treated with 1N H2SO4 to produce a sulfated material. The results reveal that sulfation causes the tetragonal phase to be formed for both types of zirconia contrary to the data before sulfation, and sulfation increases the crystallization exotherm by 150 °C.  相似文献   

11.
Hydroxy unsaturated glycerides were sought from safflower and linseed oils by partial sulfation with sulfuric acid, followed by hydrolysis of sulfate to hydroxy groups. Sulfation of oleicrich oils or their fatty acids and subsequent hydrolysis (effected conveniently with acidified barium chloride) yielded hydroxy products corresponding to 50–70% of the monoene content. Sulfation of a mixture of methyl oleate and linoleate with 78% w/w of sulfuric acid was directed mainly at the oleate component. Safflower oil was partially sulfated without side reactions using 78% or 79% w/w of sulfuric acid, the hydrolyzed products showing hydroxyl value (HV) of about 35 for a loss of 13 units of iodine value (IV). Use of more concentrated sulfuric acid, and subsequent hydrolysis, led to sulfur-containing products which include sultones. Treatment of atrans,trans, but not of acis,trans conjugated diene with sulfuric acid led to sultone formation. It is postulated that when linoleate is sulfated with strong acids, acidisomerization to atrans,trans conjugated diene occurs, probably followed by 1,4-addition of -OH and -SO3H and quick dehydration of these moieties to give a 1,4-sultone. Linseed oil was apparently sulfated without side reactions using 80% w/w sulfuric acid at 0–5 C and then hydrolyzed to a product of HV 77 and IV 159.  相似文献   

12.
Linseed and sunflower oils were heated at 275 C for 12 hr under nitrogen. The sunflower oil was also heated in a commercial fryer at 200 C for 48 hr using a 2-hr daily cycle. The cyclic fatty acid monomers (CFAM) formed during the heat treatment of the linseed oil were isolated by a combination of saponification, esterification, column chromatography on silicic acid and urea fractionation. The isolated CFAM fraction was 99% pure, the balance being some 12:2ω6. Another step was necessary to isolate the CFAM from heated sunflower oils. The urea adduct fractionation resulted in the isolation of a nonurea adduct fraction which contained a mixture of CFAM and 18:2ω6. These were further separated using high performance liquid chromatography (HPLC) on a C18 reverse phase column. Each fraction was analyzed by gas liquid chromatography and hydrogenated to determine the content of the C18 straight chain fatty acids. Presented in part at the AOCS meeting in May 1985 in Philadelphia, PA.  相似文献   

13.
Laboratory washing tests using two different kinds of standard soiled cotton were made to compare built solutions of hydrogenated tallow alcohol sulfate (HTAS), sodium methylα-sulfotallowate (NaMeαST) and linear alkylbenzenesulfonate (LAS) in hard water of 300 ppm at 60 C. Most of the experiments were at 0.25% total concentration (0.05% active ingredient plus 0.20% builder). Phosphate reduction, without loss in detergency, can be accomplished in some cases but not in others, depending both upon the detergent and the test cloth. Both cloths have shown with HTAS as the active ingredient, that reduction in phosphate builder is possible without loss in detergency. The effect of other changes in formulation has been determined. Presented at the AOCS Meeting, Minneapolis, October 1969. Deceased. ARS, USDA.  相似文献   

14.
Alkali‐metal doped sulfated zirconia catalysts were tested for the oxidative dehydrogenation of ethane into ethene. The effects of metal precursor compounds and acidic anion promoters on the catalytic activity in this reaction were studied. It was found that sulfation of zirconia increases the selectivity of ethane towards ethene. Lithium‐, sodium‐, and potassium‐doped sulfated zirconia catalysts showed quite different activities in this reaction. Sulfated zirconia doped with lithium catalysts were found to be effective for the oxidative dehydrogenation of ethane, giving over 90% selectivity to ethene and 25% ethene yield at 650 °C. © 1999 Society of Chemical Industry  相似文献   

15.
A series of sulfated silica-doped tin oxides with large surface areas (113–188 m2/g) have been successfully prepared from hydrothermal synthesis, followed by sulfation and calcination. These samples are characterized by XRD, FT-IR, TEM, nitrogen isotherms, and TG techniques, and obtained results indicate that the samples are composed of tetragonal nanocrystalline tin oxides and amorphous silica. Very interestingly, catalytic tests show that these sulfated silica-doped tin oxides are much more active than conventional sulfated tin oxides for transesterification of triacetin with methanol.  相似文献   

16.
A thermal characterization of two coal samples from Ledo and Tikak collieries of Makum coalfield, Assam, India using XRD, FT-IR, and TGA was reported in this paper. The coal samples were heated for 20, 40 and 60 min in a 1000-watt heater (temperature ∼ 250 °C) in presence of air and characterized by XRD and FT-IR spectroscopy. Both the coals contain amorphous and crystalline phases. The raw coals also contain very small peaks due to quartz, calcite, gypsum, pyrite, and chlorite. The XRD patterns were found to change upon heating. In the coals heated for 20 and 40 min, it was observed that both amorphous and crystalline parts are common in them; crystalline part being the major one in the 40 min heated samples. The XRD patterns of the samples heated for 60 min indicate the presence of major quantities of α-quartz, hematite, and chlorite in them. They also show some new peaks, which are assigned to be kaolinite, illite, magnetite and very small in comparison to the amorphous portion in raw coals. α-quartz was found to be most stable crystalline phase of silica in the coals. The crystallinity % (X-ray) of the coals heat-treated for different times was determined and found to be increasing with time of heating. The FT-IR spectra of raw and heat-treated coal samples at 250 °C were also recorded and compared. The spectra were observed to be almost similar and it was observed that few functional groups disappear on heating at 250 °C. The same coal samples were also characterized by thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques. On heat treatment in air atmosphere up to 800 °C, 20–27% weight loss occurs due to removal of various volatile materials. DTA results indicate the chemical reactivity of the coal sample initially at 80–110 °C due to loss of water, and two other major reactions at around 420 and 530 °C due to primary and secondary volatization.  相似文献   

17.
The oxidative dehydrogenation of ethane over sulfated-zirconia-supported lithium chloride catalysts has been systematically investigated. The optimal experimental parameters were obtained. It is found that sulfation of zirconia increases the catalytic activity. 2–3.5 wt% lithium chloride on sulfated zirconia catalysts exhibit high catalytic activity for oxidative dehydrogenation of ethane, with particularly high activity for ethene production. 70% selectivity to ethene at 98% ethane conversion, giving 68% ethene yield, is achieved over 3.5 wt% LiCl/SZ at 650°C.  相似文献   

18.
Dielectric loss was measured on CaF2 single crystals heated in air at 750° C for 30 hr to introduce O2- ions. The loss measurements were made in parallel and in perpendicular directions to the CaF2 surface region which contained most of the O2-. The layer containing O2- was more conducting and therefore produced a space charge relaxation near 10 kcps at 210°C. A similar loss peak was previously reported as due to oxygen ion-fluorine vacancy dipole relaxation.  相似文献   

19.
Methyl esters of dimeric fatty acids were prepared by fractionating a mixture of conjugated linoleic and oleic acids that was heated for 24 hr at 300 C in the absence of air. Rats fed diets containing less than 1% dimers showed no significant difference (P<0.05) in the growth rate, feed efficiency, liver: body weight ratio, and lipid: liver weight ratio from those fed normal diets. A lymph cannulation study using14C labeled dimers showed that ca. 0.4% of the dimers fed were absorbed within 12 hr and were transported as free acids in the lymph. Within a 28 hr period, 2% of the labeled dimers fed by gastric intubation were oxidized to14CO2, and 1% radioactivity was recovered from the urine. The metabolism of methyl oleate appeared normal for rats prefed diets containing dimers.  相似文献   

20.
采用高效液相色谱法,使用C_(18)不锈钢柱,以乙腈+0.01 mol/L碳酸铵缓冲液(体积比60∶40)为流动相,在230 nm波长下对40%丙硫菌唑悬浮剂进行定量分析。结果表明:在质量浓度为101.5~903.8mg/L时,该方法的线性相关系数为0.999 7。方法的回收率为99.77%~100.04%,相对标准偏差为0.16%。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号