Ion-selective solar crystallizer with rivulets

Jihun Choi; Jaehyun Na; Sangmin Jeon

doi:10.1016/j.isci.2023.106926

Ion-selective solar crystallizer with rivulets

iScience. 2023 May 18;26(6):106926. doi: 10.1016/j.isci.2023.106926. eCollection 2023 Jun 16.

Authors

Jihun Choi¹, Jaehyun Na¹, Sangmin Jeon¹

Affiliation

¹ Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, Republic of Korea.

Abstract

Bulk evaporation of brine is a sustainable method to obtain minerals with the inherent advantage of selective crystallization based on ion solubility differences, but it has a critical drawback of requiring a prolonged time period. In contrast, solar crystallizers based on interfacial evaporation can reduce the processing time, but their ion-selectivity may be limited due to insufficient re-dissolution and crystallization processes. This study presents the first-ever development of an ion-selective solar crystallizer featuring an asymmetrically corrugated structure (A-SC). The asymmetric mountain structure of A-SC creates V-shaped rivulets that facilitate solution transport, promoting not only evaporation but also the re-dissolution of salt formed on the mountain peaks. When A-SC was employed to evaporate a solution containing a mixture of Na⁺ and K⁺ ions, the evaporation rate was 1.51 kg/m²h and the relative concentration of Na⁺ to K⁺ in the crystallized salt was 4.45 times higher than that in the initial solution.

Keywords: Applied physics; Solar terrestrial physics.