Chitosan (CH) and cellulose are the most abundant biopolymers which could be utilized for hazardous dye removal. By incorporating TiO2 onto cellulose/CH matrix, our research aimed to achieve high metanil yellow removal by means of synergetic adsorption/photodegradation mechanism. The cellulose particles were extracted from wild grass (Imperata cylindrica L.) to obtain grass-derived cellulose (GC). Simple blending method was used to prepare TiO2/GC/CH, in which the composition was determined by simple additive weighting method (SAW). TiO2/GC/CH was characterized by means of tensile strength test (also used for SAW), Fourier Transform-Infrared (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Metanil yellow removal using TiO2/GC/CH works very well at acidic pH range. The removal follows the pseudo-second-order kinetic (R 2 = 0.997) and Langmuir isotherm (R 2 = 0.998) modellings. High qm obtained from the metanil yellow removal under UV irradiation (qm = 171.527) proves the synergism between adsorption and photodegradation. The developed TiO2/GC/CH could be potentially used in the wastewater treatment for azo dye removal.

Cellulose from grass (imperata cylindrica) had been used as reinforcement in chitosan film preparation. Cellulose was obtained from grass through hydrolysis process. Hydrolysis was conducted with different concentration of sulfuric acid at room temperature for 2 h. The results show that the highest crystallinity of cellulose was obtained at sulfuric acid concentration of 40% (v/v) on hydrolysis process. The isolated cellulose with the highest crystallinity was used as reinforcement on chitosan film preparation. Mechanical test shows addition of isolated cellulose into chitosan film improved the tensile strength. The FTIR analysis confirmed the interaction between components in the film.

The bipolar neutrosophic set is a suitable instrument to tackle the information with vagueness, complexity, and uncertainty. In this study, we improved the original EDAS (the evaluation based on distance from average solution) with bipolar neutrosophic numbers (BNNs) for a multiple-criteria group decision-making (MCGDM) problem. We calculated the average solution under all the criteria by two existing aggregation operators of BNNs. Then, we computed the positive distance and the negative distance from each alternative to the average ideal solution and determined the appraisal score of alternatives. Based on these scores, we obtained the ranking result. Finally, we demonstrated the practicability, stability, and capability of the improved EDAS method by analyzing the influence parameters and comparing results with an extended VIKOR method.

Chitosan film has attracted attention due to its advantages; it is easily modified due to numerous active sites. However, the use of chitosan film alone has limited applications. Therefore, it is necessary to modify chitosan film. In this study, chitosan was modified through addition of titanium dioxide and cellulose, extracted from grass (imperata cylindrica). Chitosan-cellulose-titanium dioxide composite film was prepared with different compositions of chitosan, cellulose and titanium dioxide. The result of the tensile test showed the addition of cellulose and titanium oxide improved tensile strength of the chitosan film. FTIR and XRD analysis confirmed the formation of chitosan-cellulose-TiO2 composite film.

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