Influence of NaOH concentration on the decolorization of crystal violet dyed cotton fabric

Mardenborough, Kristen; Florentino, Maya; Haxhari, Robert; Lin, Yu-Chung; Rafailovich, Miriam; Halada, Gary; Jung, Hye Jung; Kim, Taejin

doi:.0..

DOI: https://doi.org/10.4491/eer.2021.643

Influence of NaOH concentration on the decolorization of crystal violet dyed cotton fabric

Kristen Mardenborough¹, Maya Florentino¹, Robert Haxhari¹, Yu-Chung Lin¹, Miriam Rafailovich¹, Gary Halada¹, Hye Jung Jung²^†, and Taejin Kim¹^†

¹Department of Materials Science and Chemical Engineering, Stony Brook University, New York 11794, United States
²DaVinci College of General Education, Chung-Ang University, Seoul, South Korea

Corresponding Author: Hye Jung Jung ,Tel: +82-10-8861-1980; +1-631-632-8433, Fax: +82-2-826-6029; +1-631-632-8052, Email: jayjung@cau.ac.kr (H.J.J); taejin.kim@stonybrook.edu (T.K)
Taejin Kim ,Tel: +82-10-8861-1980; +1-631-632-8433, Fax: +82-2-826-6029; +1-631-632-8052, Email: jayjung@cau.ac.kr (H.J.J); taejin.kim@stonybrook.edu (T.K)

Received: December 28, 2021; Accepted: April 17, 2022.

ABSTRACT

Synthetic dye removal is a topic of increasing interest as textile recycling has become more popular in industries. While methods involving dye removal from wastewater effluent have been widely studied and reported on, research on decolorization of fabric itself remains quite unknown. In regard to the lack of research, this study presents cotton fabric samples dyed with crystal violet (CV) that were treated with varying concentrations of sodium hydroxide (NaOH). Fabric decolorization was studied using several characterization methods. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy data showed that the cellulose structure remained unchanged after CV and NaOH treatment. Characteristic CV peaks in the FTIR and Raman spectra were apparent only in the control sample, while the spectra of NaOH-treated samples were very similar to that of the cotton fabric. X-ray diffractometry (XRD) data also confirmed that the crystallite size of cellulose was not affected by CV and NaOH treatment. A visible violet hue remained in all NaOH-treated samples, though CV intensity was inversely proportional to NaOH concentration. The L*a*b* values were utilized to complement characterization results. As the concentration of NaOH was increased, the CIELAB parameters aligned more with those of the plain untreated fabric.