Current Analytical Chemistry    Vedat Tolga Özdemir 1 , Himmet Mert Tuğaç 1 and Özgür Arar 1,* 1 Department of Chemistry, Faculty of Science, Ege University, Izmir 35040, Turkey Abstract: Background: Cellulose is one of the most abundant, non-toxic, and renewable natural bi- opolymers. The presence of hydroxyl groups in cellulose leads to further modification of it. Prepara- tion and modification of cellulose-based sorbents and their applications on water treatment gained traction in recent years. Objective: A low-cost and eco-friendly biosorbent was designed and fabricated by introducing the acetate functional groups into cellulose for removing Beryllium (Be 2+ ) from an aqueous solution. The sorption of Be 2+ on acetate containing cellulose was evaluated for varying sorbent doses and initial solution pH values. Methods: The sorbent was prepared by a two-step oxidation process. In the initial step, cellulose re- acted with NaIO 4 and aldehyde groups were introduced to the cellulose. In the second step, newly obtained aldehyde groups were oxidized to create acetate groups. Results: The kinetics of the sorption process showed that Be 2+ uptake reached equilibrium in 3 minutes. The sorption isotherm was well fitted in the Langmuir model, and the maximum sorption capacity was 4.54mg/g. Moreover, the thermodynamic studies demonstrated that Be 2+ sorption was spontaneous and exothermic. Furthermore, the prepared sorbent can be regenerated by using 0.1 M HCl or H 2 SO 4 solutions. Conclusion: It is concluded that the removal of Be 2+ is pH-dependent and it is favorable at high solu- tion pH. The kinetics of the prepared sorbent were rapid and equilibrium attained in 3 minutes. The prepared sorbent can be regenerated with 0.1 M acid solution with > 99% efficiency. A R T I C L E H I S T O R Y Received: March 22, 2020 Revised: May 17, 2020 Accepted: June 10, 2020 DOI: 10.2174/1573411016999200719232310 Keywords: Beryllium, biopolymer, cellulose diacetate, ion-exchange, regeneration, water treatment. 1. INTRODUCTION Beryllium (Be) is a member of group IIA of the periodic table and is found in the Earth’s crust mainly as the silicate mineral beryl, Be 3 Al 2 [Si 6 O 18 ]. It is also found in many natu- ral minerals, including bertrandite, Be 4 Si 2 O 7 (OH) 2 [1, 2]. With its unmatched combination of unique properties, Be has become an indispensable metal for a wide variety of applica- tions in automotive electronics, telecommunications, aircraft industry, computers, aerospace, in modern X-ray technology, and defense equipment [3-7]. The primary source of Be compounds in water appears to be species that are released from coal-burning and other in- dustries using Be. Other sources of Be in surface water in- clude deposition of atmospheric Be and weathering of rocks and soils containing Be [8]. *Address correspondence to this author at the Department of Chemistry, Faculty of Science, Ege University, Izmir 35040, Turkey; Tel: +90323112248; E-mail: ozgurarar@gmail.com Chronic beryllium disease (CBD), which is a granuloma- tous lung disease that causes both restrictive and obstructive lung function abnormalities, is the most common chronic occupational reaction to beryllium and typically involves the lungs and skin, with isolated reports of granulomas in the liver, kidney, muscle, and lymph nodes. An important fea- ture of Be toxicity is a considerable latent period, which usu- ally lasts up to 6-10 years since significant attention to Be was paid to the occupational exposure, and yet mechanisms of Be toxicity remain to be elucidated [5, 9]. The sorption/biosorption [10-14], ion-exchange [15-17], reverse osmosis [18], and lime-neutralization [19] are the conventional methods for the removal of Be 2+ from water and wastewater. Ion exchangers are a class of functional materials that display ion exchange properties owing to the existence of fixed ionic sites bonded to their framework. They are water- insoluble, organic or inorganic, materials that capable of exchanging their active ions into those coming from the sur- 1875-6727/22 $65.00+.00 © 2022 Bentham Science Publishers Send Orders for Reprints to reprints@benthamscience.net 360 Current Analytical Chemistry, 2022, 18, 360-369 RESEARCH ARTICLE Two-pot Oxidative Preparation of Dicarboxylic Acid Containing Cellulose for the Removal of Beryllium (Be 2+ ) from Aqueous Solution