Electrochemical synthesis of zinc ricinoleate and its application in ammonia adsorption

Zinc ricinoleate (Zn(Ri)2) exhibits excellent selectivity and the capability to remove odor-active compounds, such as nitrous compounds (NH3 and organic nitrogen) and sulfurous compounds (H2S, organic sulfides, and mercaptans). In contrast with the conventional catalyst-(or enzyme)-aided process, in this study, Zn(Ri)2 was prepared on zinc foil by a facile electrochemical approach. The electrochemically synthesized Zn(Ri)2 was characterized and compared to commercially available Zn(Ri)2, which clearly indicated that the average size and the production yield are strongly dependent on the external bias and anodization time: an increase in the diameter from 9.3 µm at 30 V to 15.2 µm at 80 V. In particular, an external bias of 80 V afforded the most stable particle structure and highest production yield. During anodization, the particles agglomerate and grow to form larger particles. With a distinct spherical morphology, the increased surface area contributes to the enhanced odor-removing capacity of 88% in 30 min, which is 2.3 times stronger than that of the commercial product.