Study on Adsorption Characteristics of Lead in Simulates Apple Juice by L-lysine Functionalized Cellulose

L-lysine functionalized cellulose-based lead adsorbents were prepared. The microcrystalline cellulose (MCC) and cellulose nanofiber (CNF) were performed as the matrix and L-lysine was used as the grafted monomer. In this study, the adsorption performance of the adsorbents for lead in fruit juice was explored. And the effects of sugars and organic acids on adsorption properties in fruit juice were deeply explored. Both L-lysine functionalized sodium periodate-oxidized-MCC (L-g-POCM) and L-lysine functionalized tetramethylpiperidine system-oxidized-CNF (L-g-TOCF) had excellent adsorption efficiency on lead ions, reaching 77.36% and 96.16%, respectively. The sugar solution was neutral. It had weak competitive adsorption with lead ions. The organic acids with high acidity had strong competitive adsorption with lead ions. Compared with L-g-POCM, L-g-TOCF was less affected. At pH less than 4, the adsorption efficiency of L-g-TOCF was strongly inhibited, as low as 7.54%. When pH greater than 4, it reached up to 92.18%. Thus, L-g-TOCF have a promising prospect of removal heavy metals in low-acid fruit juices.