Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

Abstract

There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

Valorization of Agro-industrial Waste from Peanuts for Sustainable Natural Dye Production: Focus on Adsorption Mechanisms, Ultraviolet Protection, and Antimicrobial Properties of Dyed Wool Fabric

“…The specific rate of adsorption decreases from 0.94 to 0.37 with an increase in temperature from 50 to 90 °C, confirming the electrostatic and exothermic effects of this particular adsorption process. Very low rate constants ( k 2 ) and a very low adsorption rate ( r i ) are associated with a large half-time of dyeing ( t 1/2 ) due to the presence of a thin protective wax layer on the wool surface resulting in limited propagation or diffusion of color components to the interior of the fiber …”

“…Very low rate constants (k 2 ) and a very low adsorption rate (r i ) are associated with a large half-time of dyeing (t 1/2 ) due to the presence of a thin protective wax layer on the wool surface resulting in limited propagation or diffusion of color components to the interior of the fiber. 56 Adsorption Isotherms. Isotherm parameters for wool dyeing with peanut skin dye were designed by fitting the adsorption data to Langmuir, Freundlich, Hill, and Sips isotherm models.…”

“…The Sips isotherm represents the limiting behavior of Langmuir and Freundlich adsorption models. 56 This model takes into account localized forces without adsorbate− adsorbate interactions. Low C e values reduce the Sips equation to the Freundlich model with van der Waals forces as the sole interactions.…”

Ultrasonic-Aided Co-Precipitation of Tannins and Chitosan Ammonium Salt on Cotton Fabric for Antimicrobial and Ultraviolet-Shielding Properties: An Efficient, Colourless, and Eco-Finishing Strategy

“…In general, the whole adsorption process was a rate-controlling type which indicated the chemisorption mechanism [29]. As the temperature rose from 70 • C to 90 • C, the t 1/2 decreased dramatically, whilst k 2 and hi increased.…”

Development of Arduino Uno-Based TCS3200 Color Sensor and Its Application on the Determination of Rhodamine B Level in Syrup

“…The wool thread was used to extract rhodamine B-containing samples in an acidic environment. A comparative study has reported that wool thread has the highest dye adsorption as compared with silk and nylon [25]. Adsorption of dye analyte in wool thread is determined by its O-and N-containing functional groups, which has been reported in many published papers [26][27][28].…”