Shella Permatasari Santoso, Artik Elisa Angkawijaya, Vania Bundjaja, Chang-Wei Hsieh, Alchris Woo Go, Maria Yuliana, Hsien-Yi Hsu, Phuong Lan Tran-Nguyen, Felycia Edi Soetaredjo, Suryadi Ismadji
The development of porous adsorbent materials from renewable resources for water and wastewater treatment has received considerable interest from academia and industry. This work aims to synthesize composite hydrogel from the combination of guar gum (a neutral galactomannan polysaccharide) and TiO2. The TiO2-embedded guar gum hydrogel (TiO2@GGH) was utilized to remove methylene blue through adsorption and photodegradation. The presence of TiO2 particles in the hydrogel matrix (TiO2@GGH) was confirmed by scanning electron microscopy-energy dispersive X-ray and X-ray photoelectron spectroscopy analysis. The mercury intrusion and N2 sorption isotherm indicate the macroporous structure of the TiO2@GGH composite, showing the presence of pore sizes ~420 μm. The dye removal efficiency of the GGH and TiO2@GGH was evaluated in batch mode at ambient temperature under varying pH. The effect of UV radiation on the dye removal efficiency was also assessed. The results demonstrated that the highest dye removal was recorded at pH 10, with the equilibrium condition achieved within 5 h. UV radiation was shown to enhance dye removal. The maximum adsorption capacity of TiO2@GGH is 198.61 mg g−1, while GGH sorbent is 188.53 mg g−1. The results imply that UV radiation gives rise to the photodegradation effect. © 2021 Elsevier B.V.
Chemical Engineering Department, Faculty of Engineering, Widya Mandala Surabaya Catholic University, Jl. Kalijudan No. 37, Surabaya, 60114, East Java, Indonesia; Chemical Engineering Department, National Taiwan University of Science and Technology, #43 Keelung Rd., Sec. 4, Da'an Dist., Taipei, 10607, Taiwan; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, #43 Keelung Rd., Sec. 4, Da'an Dist., Taipei, 10607, Taiwan; Department of Food Science and Biotechnology, National Chung Hsing University, No. 145 Xingda Road, 402, South District, Taichung City, Taiwan; School of Energy and Environment, Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon Tong, Hong Kong; Shenzhen Research Institute of City University of Hong Kong, Shenzhen, 518057, China; Mechanical Engineering Department, Can Tho University, 3/2 Street, Ninh Kieu Dist., Can Tho City, Viet Nam