Mercury from the traditional gold mining activities in Aceh Jaya Regency causes water source and thus residents are exposed to mercury metals. In organic and inorganic conditions, mercury is toxic to the human body, causes damage to the nerve system, kidney failure, heart failure, blood pressure disorders, and damage to the immune system. The problem of mercury contamination can be chemically solved in various ways. This research uses polyurethane foam to adsorb mercury from water. The adsorption and selectivity of polyurethane foam adsorption can be improved through modification with Chitosan. In this research, preheating temperature, glycerol and toluene di-isocyanate (TDI) compositions greatly affect the physical form of foam. The condition under which optimal glycerol composition used for synthesizing the polyurethane foams is 20% (w/w of mixture A). This glycerol composition results in polyurethane foams with an optimum ratio of the mixture A/TDI/distilled water of 2 : 1 : 1. The best adsorption is obtained with polyurethane foam added by 2.5% Chitosan. The optimum mercury adsorption 25% is resulted from the operating time of 60 minutes with adsorption capacity of 0.313 mg/g. For Chitosan modified polyurethane foam, research points out that the reaction is the second order reaction. The result concluded that the polymer has semi crystalline crystallization and melting temperatures.

Modification of chitosan using amino acids (AA) obtained from the protein hydrolysis process of tofu wastewater (TW) and TiO2 had been successfully prepared and applied in methylene blue (MB) removal from aqueous solutions. Based on the XRD results, the addition of AA and TiO2 slightly changed the crystallinity properties of chitosan. FT-IR results confirmed the formation of Chitosan-amino acid/TiO2 films (CATF). The results of TGA and DSC showed that the addition of AA decreased the thermal stability of the film, but the addition of TiO2 was able to increase the thermal stability of the film. The addition of AA and TiO2 to chitosan improved the mechanical characteristics of chitosan, according to the tensile strength data. Based on the adsorption kinetics, the removal of MB followed a pseudo second order model (PSO). The isotherm model in the adsorption process follows the Langmuir isotherm model and the maximum adsorption capacity is 64.95 mg/g. Based on the regeneration test, the CATF could be regenerated.

The fabrication of Cellulose nanocrystals (CNCs) from sugarcane baggasse (SCB) using acid hydrolysis at various concentrations (5, 10, 20, 25, and 30%) and ultrasound-assisted is presented in this paper. The fabricated CNCs were also thoroughly analyzed using Fourier Transform Infrared Spectroscopy (FTIR) to investigate surface functional groups and X-ray diffraction (XRD) to investigate structural properties. The particle size distribution following the ultrasonication procedure was also measured using a particle size analyzer (PSA) in this investigation. The content of hemicellulose and lignin will decrease as the concentration of HCl in the hydrolysis process increase. On the other hand, the α-cellulose content was increasing. The best concentration of HCl is 20%. FTIR data shows that a sharper increase in intensity can be seen in the HCl 10% and HCl 20% samples. XRD data revealed that the crystal size was 2.732 nm and the index crystallinity of CNCs was 63,57%, while PSA analysis revealed that the average particle size was 125.1 nm.