Dyeing Property and Adsorption Kinetics of Reactive Dyes for Cotton Textiles in Salt-Free Non-Aqueous Dyeing Systems

Abstract

In recent years, new concepts in textile dyeing technology have been investigated which aim to decrease the use of chemicals and the emission of water. In this work, dyeing of cotton textiles with reactive dyes has been investigated in a silicone non-aqueous dyeing system. Compared with conventional aqueous dyeing, almost 100% of reactive dyes can be adsorbed on cotton textiles without using any salts in non-aqueous dyeing systems, and the fixation of dye is also higher (80%~90% for non-aqueous dyeing vs. 40%~50% for traditional dyeing). The pseudo-second-order kinetic model can best describe the adsorption and equilibrium of reactive dyes in the non-aqueous dyeing systems as well as in the traditional water dyeing system. In the non-aqueous dyeing systems, the adsorption equilibrium of reactive dyes can be reached quickly. Particularly in the siloxane non-aqueous dyeing system, the adsorption equilibrium time of reactive dye is only 5–10 min at 25 °C, whereas more time is needed at 60 °C in the water dyeing system. The surface tension of non-aqueous media influences the adsorption rate of dye. The lower the surface tension, the faster the adsorption rate of reactive dye, and the higher the final uptake of dye. As a result, non-aqueous dyeing technology provides an innovative approach to increase dye uptake under a low dyeing temperature, in addition to making large water savings.

Inhibitive Effect of NaCl and Citric Acid on the Colour Yield of Acid Dye on Nylon Fabric

“…This shows that there is a high affinity between fiber and dye. 1) Pseudo-first-order-kinetic model The fitting of the pseudo first-order-kinetic model was done using Langergren's equation [16] ( ) q t (mg/g) and q e (mg/g) are quantity of dye adsorbed at different time t (min)of dyeing and at equilibrium, k 1 is the rate constant of the pseudo first order kinetic model. Using Equation (9) a graph of ( ) ln e t q q − versus t was plotted as shown in Figure 6 and was used to calculate R 2 the correlation coefficient.…”

“…2) Pseudo-second-order-kinetic model The pseudo second order kinetic model studied with the following equation [16]…”

Non‐aqueous dyeing of cotton fibre with reactive dyes: A review

“…With the aim of developing a whole system of D5 reactive dyeing of cotton fibre, Fu et al reported an optimised soaping process for cotton fabric dyed in a D5 suspension dyeing system using Hexadecyl trimethyl ammonium bromide (HTAB) as a soaping agent, and their results showed that the water consumption of the entire process was only 7‐fold that of fabric mass. With the use of different solvents as dyeing media, Wang et al studied the dyeing properties and adsorption kinetics of reactive dyes for cotton woven fabric in a dye/solvent non‐aqueous dyeing system, while Pei et al investigated the diffusion mechanism of an aqueous solution and the swelling of cotton and viscose yarns in a dye/solvent non‐aqueous dyeing system.…”

Impact of operating conditions for the continuous‐flow removal of dye effluents in a fixed‐bed reactor using light expanded clay aggregate as a green adsorbent with ultrasound‐assisted desorption

“…One of the major group of contaminant that should be avoided to discharge them in valuable water resources are dyes. Dyes are organic aromatic materials that have many applications in coloring wools, cottons, strings, and other cellulosic materials 2 and classified as basic, anthraquinon, azo, acid, metal complex, disperse, and mordant dyes. Their entrance in water resources causes many problems.…”