Molecular design targets and optimization of low-temperature thermal desalination systems

Abstract

Directional solvent extraction (DSE) is an emerging membrane-free liquid-liquid extraction process to desalinate water using low-grade heat. Several unique features make DSE a potentially disruptive desalination technology: 1) it is thermally driven and utilizes low-grade heat; 2) it does not require the use of membranes; 3) there are opportunities to intensify, modularize and customize

Computational and experimental study of different brines in temperature swing solvent extraction desalination with amine solvents

“…Separating the biphasic mixture recovers the purified water and simultaneously regenerates the solvent [8]. Several different solvents have been evaluated for TSSE, including long-chain fatty acids [16][17][18], secondary and tertiary amines [11][12][13][14]19], and imidazolium-based ionic liquids [20].…”

Process intensification in Desalination operation in mesoscale systems

“…The application of infra red radiation in preheating section and the meso scale reactor shall reside in an enclosure consisting of infrared heating device of 100 W and 220 V, [27] the process will increase the working temperature for the DSE process, cooling is planned to achieve via a heat exchanger or a chiller or, atmospheric cooling. The total exergy and energy calculations will be conducted to see the energy requirement for the process [23,2]. Water inlet salinity will be kept around e.g.…”

“…Directional solvent extraction (DSE) is an emerging membrane-free liquid-liquid extraction process to desalinate water using low-grade heat [1,2,3,4]. Several unique features make DSE a potentially desalination technology: a) it is thermally driven and utilizes low-grade heat; b) it does not require the use of membranes; c) there are opportunities to intensify, modularize and customize the process; d) there is a vast solvent molecular design space [5,6].…”

“…The features of DSE are several and distinct and the solvent can be reutilized. (i) DSE processis a membrane free operation, (ii) DSE operates in liquid state which reduces the size and complexity of the equipment, (iii) DSE can be paired with state-of-art and economic heat sources such as infra red assisted heater[27,2,28,29]…”

1-Propyl-4(5)-Methylimidazole Isomers for Temperature Swing Solvent Extraction

“…However, this technique did not gain much traction at that time due to the significant amount of residual solvent in the final product water. Over the past decade, a number of studies have revived the TSSE technique by utilizing long chain carboxylic acids (e.g., octanoic, decanoic) instead of amines [ 1 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. The benefit of using these carboxylic acids is the residual levels of solvent in the final product water are at or below the concentrations of these solvents found in dairy products (i.e., FDA approved levels).…”