Detergency temperature effect

The present paper deals with kinetics of coagulation of Phthallylsulfathiazole stabilized xylene in water emulsion in the presence of some cationic detergents. Rate of flocculation, rate of coalescence and rate of creaming have been determined. To estimate the stability of the present systems their zeta potentials have been measured and stability factors calculated. Temperature effect on the system was also studied. 

It is evident from the date recorded in Table I that at higher temperature coalescence rate constant is higher, that is in order of kc30° < kc40° < c50° The temperature effect for all detergents was found to be in the order LPC < CTAB < CPC < CPB. This implies that in the presence of CPB the coalescence rate constant of the emulsions increases enormously (e.g. four to six times for every 10°C rise of temperature) with the rise of temperature whereas in the presence of LPC the increase in the rate is not that pronounced. 

Turro, N.J., Aikawa, M., Yekta, A. A comparison of intermolecular and intramolecular excimer formation in detergent solutions temperature effects and microviscosity measurements. J. Am. Chem. Soc. 1979, 101(3), 772-774. 

Fig. 2. Effect of wash temperature on removal of sebum, O lanolin, and lard from cotton (0.25% built detergent) (48). D, Represents sebum removal...

AH detergent proteases are destabilized by linear alkylbenzenesulfonate (LAS), the most common type of anionic surfactant in detergents. The higher the LAS concentration and wash temperature, the greater the inactivation of the enzyme. The presence of nonionic surfactants, however, counteracts the negative effect of LAS. Almost aH detergents contain some nonionic surfactant therefore, the stabHity of proteases in a washing context is not problematic. 

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