Efficient Degradation of Rhodamine B Dye through Hand Warmer Heterogeneous Activation of Persulfate

Abstract

In this study, an innovative method for RhB (Rhodamine B) degradation in a persulfate (PS) and hand warmer heterogeneous activation system was investigated. The hand warmer showed better catalytic performance and excellent reusability in terms of PS activation. The reaction rate constants of RhB removal in the hand warmer/PS process (0.354 min−1) were much faster than those in other PS- and Fe-related processes (0.010–0.233 min−1) at pH 7. The iron in the hand warmer is the main active ingredient to catalyze PS, and activated carbon, salt, and H+/OH− accelerate the activated reaction due to the formation of micro-batteries in the solution. Moreover, the catalyst of the hand warmer showed excellent stability and reusability with a low level of iron leaching. This new, effective, inexpensive, repeatable, and environmentally friendly catalyst combined with PS has promising prospects for the removal of dyes from industrial wastewater.