Construction of novel phytic acid-based lignin for highly efficient treatment of low-level radioactive wastewater: Synthesis, performance, and mechanistic insights

Abstract

Low-level radioactive wastewater exhibits a serious jeopardize to the ecology, natural environment, and human health. Hence, this study constructed a novel adsorbent (PA-EHL) via a simple grafting reaction by using enzymatic hydrolysis lignin waste (EHL) and phytic acid (PA) as raw materials. The adsorption capacity of PA-EHL was evaluated using Ce(III) and La(III) as the representative nuclides. PA grafting significantly promoted the formation of good textural properties, high crystalline stability, and abundant phosphorous/oxygen-containing functional groups on lignin surface, thus appreciably strengthening the adsorption performance. The PA-EHL exhibited high adsorption capacity for Ce(III) with 743.16 and for La(III) with 735.60 mg/g within 240 min. In addition, the efficient ability of PA-EHL for adsorbing Ce(III) and La(III) displayed superior anti-ions interference abilities, excellent reusability, and extremely low operational fees. The P-O on PA-EHL surface as the main active site, displayed strong binding affinity for Ce(III) and La(III) via electrostatic attraction-dominated physisorption and complexation-dominated chemisorption, respectively. In summary, the constructed PA-EHL addresses the drawback of conventional adsorbents in view of complicated fabrication process, low adsorption capacity, inferior anti-ions interference abilities, and expensive cost, which makes it as a potential adsorbent in industrial application for the highly efficient treatment of low-level radioactive wastewater.