Investigating the Mechanism and Performance of Cellulose Fibers Recovered from Newspaper Waste and Functionalized with Amino Groups in Removal of Crystal Violet Dye

Crystal violet is known as one of the most famous and common dyes, widely used as a colored substance in the leather, textile and paper industries. Crystal violet is toxic and dangerous for humans and animals at concentration even lower than 1 ppb; it has carcinogenic and mutagenic properties as well as harmful effects on the skin. So, this study was conducted with the aim of investigating the removal of crystal violet (CV) dye using cellulose recovered from waste paper and functionalized with amine groups.The study was performed in three general stages: 1) preparation of the adsorbent, 2) designing the experiments with R software 3) experimental study and data analysis. Absorption tests were carried out considering the desired range of influencing factors in absorption, including dye concentration, pH, adsorbent dose and contact time at room temperature. Eventually, the obtained results were statistically analyzed using R software.In some of experiments, the variables of adsorbent dose, pH, dye concentration and reaction time were investigated to remove CV dye from the aqueous phase. The response surface method (RSM) was selected to study the effect of interaction independent input variables and a dependent output response variable (crystal violet removal efficiency). The Results including p-value (2.2 × 10-16), high F-value (560.633), multi. R2 (0.9929), adj. R-squad (0.9882) and absence of significance of the model's lack-of fit (0.147) showed that the diminished second order- model is very significant for the elimination of crystal violet dye by the adsorbent. The most removal efficiency of crystal violet dye was found to be 95.1%, under optimal operational parameters including: absorbent cycle rate of 0.125 g/liter, pH equal to 9, contact time 92.5 min, and CV concentration of 14 mg/liter. In addition, the results indicated that the pseudo second order kinetic model is the most suitable model for dye absorption on cellulose absorbent, and the absorption behavior of crystal violet dye on functionalized cellulose follows the Freundlich model (R2=0.9955).Overall, the results showed that the adsorbent created from waste newspaper is an efficient and cheap method to remove crystal violet from aqueous solutions.