A new approach to continuous soap making-constant composition control

Summary A new continuous process for the manufacture of soap is described, detailing the three main operations in soapmaking, that is, saponification, washing, and fitting. In the new process all operations involved in the production of soap are carried out in a hermetically closed system. The amounts of lye necessary for the saponification as well as of brine for the washing and fitting operations are regulated by the automatic constant-composition control system, which eliminates the older method of control of the soapmaking process by cumbersome chemical analyses. The process is based on the use of the Hermetic separator, a centrifuge of special design which allows the regulation of the separation efficiency during operation and which prevents any admixture or contact of the soap with air and consequently any oxidation of the product during processing. All type of soap, high grade toilet soap as well as laundry soap and industrial soaps, can be produced by this process, which is characterized by high flexibility, low operation-costs, and a high quality of the finished product. Presented at the fall meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958.     

Prüfung desinfizierender Handwaschmittel

Examination of Disinfecting Hand Cleaning Agents 8 disinfecting hand cleaning agents marketed in Germany and a conventional liquid soap were compared with respect to their ability for reducing the germ count in hand washing tests. Under identical conditions of application (identical quantity of product and duration of application) only three of the agents proved to be significantly superior to the conventional liquid soap. Compared to the liquid soap these three agents showed an improvement of germ reduction in the order of three to hundred times of the basic value.     

Discoloration of Nylon 6.6—A Comparison of some Contributory Factors

A wear trial of full-length white nylon underskirts was conducted to compare the contributions to discoloration due to changes in the nylon polymer, to the spin finish, to a fluorescent brightener, to the soap used in washing, to skin fat, and to air-borne dirt. The underskirts, in absence and in presence of spin finish and of brightener, were worn according to a schedule and washed in a standardised way using a low concentration of soap. Greyness and yellowness increased steadily, the greyness being greater in the upper than in the lower parts of the garments. After the wear trial, retained fat was extracted from the garments with organic solvents, weighed and analysed. The high discoloration found in all garments was due mainly to the absorption of skin fat and soap and the associated retention of particulate dirt. Fat and yellow colouring matter could be transferred during washing. Spin finish and fluorescent brightener usually only slightly affected the discoloration. There was negligible discoloration due to the storage of the nylon, repeated washing of clean fabric, and repeated exposure to dirty air followed by washing.     

Challenging the Traditional Counter‐Current Water Circulation System Case: Washing of Soap in a Kraft Pulp Fibreline

Would it be possible to challenge the traditional counter‐current water circulation system in a way that enables better soap washability, and thus improves process runnability in the kraft pulp fibreline? New water circulation alternatives were simulated in order to find ways to modify dissolved solids contents in the liquors and thus to improve soap washability. An application of using different fractions of liquors in dilution washing proved to be an interesting alternative. The presented modification principles should be applicable also in other branches of the chemical industry, especially when solubility is a limiting factor in washing.     

Ein Membrantrennverfahren zur NaOH-Rückgewinnung

Membrane Process for Caustic Soda Recycling In the list of the largest volume chemical consumed worldwide caustic soda ranks in the top ten. Sodium hydroxide is being consumed among other applications for the edible oil and fat refining, in the soap industry as well as in the beverage industry (bottle washing). Most of the caustic soda is produced by electrolysis, where for every kg of caustic 890 gramms of chlorine are produced. Recent measures of environmental protection and diminishing acceptance of products containing chloride leads to reduction in chlorine demand. Consequently, a shortage in caustic supply is unavoidable. KREBS SWISS has been engaged since some time with a new membrane process for caustic soda recycling, based on the principle of ultrafiltration resp. nanofiltration. Some fields of application are listed. Finally the way how to proceed as well as some results are presented.     

Seifenspaltung – kontinuierlich und umweltfreundlich

Soap Splitting – Continuous and Ecologically Harmless In the classical refining of vegetable oils the free fatty acids are saponified and separated from oil by centrifuging. The centrifuged soap solution also contains neutral oil and non hydrationable sliming substances. The resulting emulsion impedes splitting and the separation of the aqueous phase from the oily fatty acid phase. Therefore you often work with high surplus of sulphuric acid and direct vapour for heating and stirring. The direct vapour carries away fatty acid and sulphuric acid as aerosol and must be washed before drawing out into the enviroment. If the mixture from the centrifuges undergoes a saponification reaction, splitting can be continuously carried out by addition of sulphuric acid, regulated by the pH-value, without direct vapour. Thus an important requirement for an ecologically harmless procedure of soap splitting is given.     

The germicidal activity of rosin soap and fatty acid-rosin soap as indicated by hand-washing experiments

Summary and Conclusions Price’s procedure as slightly modified (4) was used for studying the germicidal action of cleaning agents on the hands and showed that rosin soap and a commercial soap containing rosin were more active germicidally on the bacteria normally found on human skin than the usual commercial fatty acid soaps free from rosin soap. The experiments indicate that the lather of a 10-percent coconut oil soap solution and of a 10-percent coconut oil-rosin soap solution are germicidally active against the organisms removed. However, three 2-minute washes with these soap solutions had little effect on the bacteria not removed from the hands. The use of a 10-percent rosin soap solution in the same manner had a marked germicidal effect against both the organisms removed and those remaining. The lather of a commercial soap containing rosin soap was shown to be germicidally active, but three 2-minute washes had only a slight effect on the resident flora. However, the regular use of this soap daily for one week led to substantial reduction of both the transient and resident flora of the hands. The evidence of germicidal activity of rosin soaps and soaps containing rosin, both with regard to these hand-washing experiments and the “in vitro” (7) experiments, indicates that wider consideration might well be given this type of soap where germicidal activity is of importance. L. S. Stuart was employed in the Industrial-Farm Products Research Division when this work was done.     

Polyhydric alcohol esters of α-sulfo fatty acids

Direct esterification of α-sulfopalmitic and α-sulfostearic acids with excess ethylene glycol, glycerol, pentaerythritol and 2-methoxyethanol was carried out in carbon tetrachloride to give products containing essentially monoesters. Surface active properties of these compounds were measured with emphasis on washing ability in combination with soap. The detergency of these esters was compared with those of hexitol and sucrose α-sulfo fatty acid esters. Although the esters had moderate lime soap dispersing ability, their detergency showed synergism when combined with soap. Deceased. East. Market. Nutr. Res. Div., ARS, USDA.     

Resistance to Hardness of Water as an Analytical Parameter of Soap Quality

Resistance of soap to hardness of water as reflected by its ability to lather in hard water has been tried as as analytical parameter to assess the quality and hence effectiveness of the soap. The resistance of a soap to hardness of water can be considered to be the sum total effect of four factors: 1. Composition of the fat base, 2. solubility of the soap at the washing temperature, 3. polymorphism of soap crystals and 4. nature and proportions of additives in the soap. The method thus helps in assessing the quality of the soap with regard to these factors and in working out the economics of its use.     

Desorption of hydrolysed reactive dyes from wool

The desorption of the hydrolysed forms of nine reactive dyes from wool has been examined in soap solution (ISO 2 test) and in urea-surfactant solution. It was found that the desorption of the hydrolysed dyes was slower in soap solution than in the urea-surfactant solution. After the standard 45 min of the ISO 2 washing test equilibrium was not reached, while after 60 min in the urea-surfactant solution equilibrium desorption was reached with most of the hydrolysed dyes. These findings clearly explain the discrepencies which sometimes occur between the two methods when used to assess wash fastness in relation to fixation ratios. If the time of the ISO 2 test is extended until equilibrium desorption is achieved then the two methods give essentially the same results. It was also found that the desorption rate constants appear to be inversely related to the molecular weights of the hydrolysed dyes.     

Soap-based detergent formulations: VIII. N-Alkylsulfosuccinamates as lime soap dispersants

A series of sodium methyl N-alkylsulfosuccinamates was prepared by the reaction of methyl N-alkylmaleamates with sodium bisulfite in aqueous ethanol. The surface-active properties and detergency of these derivatives were compared with those of a series of disodium N-alkylsulfosuccinamates prepared by the reaction of sodium sulfite with N-alkylmaleamic acid in water. The ester derivatives generally showed good lime soap dispersing requirement and washing ability in combination with soap, where-as the disodium salts were somewhat deficient in these properties and exhibited good washing ability only at 0.2% concentration with the surfactant as the sole component.     

Ethanolysis of Refined Soybean Oil Assisted by Sodium and Potassium Hydroxides

The ethanolysis of refined soybean oil was investigated through a 2³ experimental design that was carried out under the following levels: ethanol:oil molar ratios (MR) of 6:1 and 12:1, NaOH concentrations of 0.3 and 1.0 wt% in relation to the oil mass, and reaction temperatures of 30 and 70 °C. The ethanol:oil MR and the alkali concentration had an almost equivalent influence on the reaction yield, whereas the influence of increased reaction temperatures was very limited and higher catalyst concentrations led to greater yield losses due to the formation of soap. Ethyl ester yields of 97.2% were obtained at 70 °C, MR of 12:1 and 0.3 wt% NaOH. Replacement of 0.3 wt% NaOH by 1.0 wt% KOH under the same reaction conditions led to lower ester yields. Likewise the former, KOH provided the maximum ester yield (95.6%) at the highest molar ratio (12:1), with the reaction temperature having little influence on the catalyst performance. Ester yields beyond 98% were only achieved when a second ethanolysis stage was included in the process. In this regard, the application of 2 wt% Magnesol^® after the first ethanolysis stage eliminated the need for water washing prior to the second ethanolysis stage and helped to generate a final product with less contaminating unreacted glycerides.     

Some problems involved in the water wash of neutralized vegetable oils

Summary An investigation of the removal of soap from neutralized vegetable oils by washing with water has shown that some oils are obtained practically soap-free after only one water wash whereas the soap in other oils cannot be removed even by repeated washing. Coconut, palm, and olive oils are easily washed whereas linseed and rapeseed oils are not. Peanut, sunflowerseed, soybean, and cottonseed oils are sometimes washable and sometimes not. With unwashable oils different methods for soap determination give inconsistent results because calcium and magnesium soaps, or other naturally-occurring compounds of these metals, are not determined to the same extent by these methods. Calcium and magnesium in the crude oils are probably combined with phosphatides or other lipids and remain to some extent in this state after neutralization. Calcium and magnesium present as soaps or as any other compound may be detected easily in crude, neutralized, and washed oils by the titration method of Wolff. Washability of neutralized oils may be improved in a number of ways; the most efficient is pre-treatment with concentrated phosphoric acid or re-refining with a mixture of sodium hydroxide and sodium carbonate. Either of these treatments can be applied in batch or continuous refining processes. To prevent contamination of washable oils with calcium and magnesium, soft water should be used for washing and in preparation of refining solutions.     

Soap-based detergent formulations: X. Nature of detergent deposits

The cumulative deposition of detergent residue on unsoiled cotton and polyester-cotton permanent press finish cloth was determined for a variety of detergent formulations after washing 25 consecutive times in 300 ppm hard water in a laboratory Tergotometer. Included in this study were: a phosphate-built laundry detergent, two carbonate-built detergents, tallow soap and various tallow soap formulations with anionic and amphoteric lime soap dispersing agents, and a glassy sodium silicate. Sample swatches washed with each formulation were analyzed for calcium, magnesium, and organic acid content. Fabric washed with the carbonate detergents showed the highest calcium and magnesium content, while those washed with the phosphate detergent and the soap-lime soap dispersant-builder formulations had the lowest. Fabric washed with soap alone had a much higher fatty acid residue than those washed with the other detergent formulations. However, the amount of organic acids left on the fabric after washing with a soap-lime soap dispersing agent formulation was no greater than that produced by phosphate- and carbonate-built detergents. The presence or absence of deposits also was verified visually with a scanning electron microscope. Each formulation also was tested for detergency by measuring the soil buildup in a multiwash procedure. Generally, the buildup of soil paralleled the deposit of detergent residue on the unsoiled cloths.     

Rosin/acid oil-based liquid soap

Soapstock was converted into a liquid soap from its acid oil and formulated with varying amounts of rosin. The characteristics of the acid oil and rosin were experimentally estimated. Liquid soaps were characterized by density, pH, total fatty matter, free caustic alkali, critical micelle concentration, foaming capacity, wetting power, and washing performance. The foaming results indicated that the liquid soap is best used as an ingredient in a washing-machine detergent. The dark aspect of a formulation with 10% rosin precluded higher substitution.     

铬污染土壤修复技术研究

Cr(Ⅵ)是世界公认的有毒致癌物,对人类健康有严重危害。随着铬化工行业的发展,铬污染问题,尤其是土壤的铬污染问题,越来越严重。描述了铬在土壤中的形态变化及土壤对铬的吸附特性,详细介绍了隔离包埋法、固化稳定法、化学还原法、土壤淋洗法、电化学修复法、微生物修复法和植物修复法等多种铬污染土壤的修复方法,并展望了当前土壤铬污染治理的发展趋势,为科学合理地处理土壤修复问题提供了方向。     

PCB电镀中极化曲线的应用

通过对PCB镀铜液的阴极极化曲线的测量,研究了添加剂的作用及其影响规律;分析了极化曲线与镀层质量的关系.通过极化曲线,可以分析镀液是否受污染,若已被污染,则可以确认污染源;确定适宜的工作电流密度,从而保证镀层质量.     

Local Whittle estimation of the memory parameter in presence of deterministic components

We discuss the estimation of the order of integration of a fractional process that may be contaminated by a time‐varying deterministic trend or by a break in the mean. We show that in some cases the estimate may still be consistent and asymptotically normally distributed even when the order of magnitude of the spectral density of the fractional process does not dominate the one of the periodogram of the contaminating term. If trimming is introduced, stronger deterministic components may be neglected. The performance of the estimate in small samples is studied in a Monte Carlo experiment.     

Über die Entwicklung neuer,verbesserter Enzyme für den Gebrauch in Waschmitteln

Development of New Improved Enzymes for Application in Washing Agents The author deals with microbiological screening for suitable bacilli, taxonomic investigations, optimization of growth parameters, isolation of proteolytic enzymes produced during the metabolism of various bacteria, chemical investigation of isolated enzymes, as well as practical assay of their effectiveness in various compositions of washing agents. Toxicological studies too are carried out in certain cases, as required. Moreover, the technical properties of these surfactant additives are described.     

Kontaminationsmöglichkeiten durch Anwendung von Kosmetika

Possible Contaminations by the Use of Cosmetics Modern hygienic manufacturing processes ensure that cosmetics free of pathogenic germs are delivered by the producer to the consumer. In this respect the situation has changed compared to past years. Possible contaminations occur today mainly at the consumer's side, for example if cosmetics in open containers are used commonly, as practiced in families. Conditions that lead to skin infection are discussed. Pyodermia resulting from contaminated cosmetics have not been observed by the author during the past 24 years.