Cyclopentane hydrates – A candidate for desalination?

Abstract

This article presents a systematic review on the past developments of Hydrate-Based Desalination process using Cyclopentane as hydrate guest. This is the first review that covers all required fundamental data, such as multiphase equilibria data, kinetics, morphology, or physical properties of cyclopentane hydrates, in order to develop an effective and sustainable desalination process. Furthermore, this state-of-the-art describes research and commercialization perspectives. When compared to traditional applications, cyclopentane hydrate-based desalination process could be a promising solution. Indeed, it operates under normal atmospheric pressure, lower operation energies are required, etc… However, there are some challenges yet to overcome. A decision aid in the form of a diagram is proposed for a new cyclopentane hydrates-based desalination process. Hopefully, concepts reviewed in this study will suggest new ideas to advance technical solutions in order to make commercial hydrate-based desalination processes a reality.

A novel stirred microcalorimetric cell for DSC measurements applied to the study of ice slurries and clathrate hydrates

“…The arithmetic mean of the results obtained from 4 experiments carried out under stirred conditions gives the following robust estimation for the two properties: T diss = 6.9 ± 0.4 • C and H diss = 109,900 ± 4600 J mol −1 of CP (359 ± 15 J g −1 of water). Our experimental CP-hydrate dissociation temperature value is in perfect agreement with literature data, as the most reliable equilibrium temperature range for these hydrates is considered to be between 6.6 and 7.2 • C (Ho- Van et al, 2019).The dissociation enthalpy value is also in very good agreement with those of Nakajima et al (2008) (106,900 J mol −1 of CP) and Delroisse et al (2018) (115,400 ± 7600 J mol −1 of CP), but substantially higher than the values proposed by Zhang et al (2004) and Lee et al (2019). In addition to the assumptions given by Nakajima et al (2008) to explain the difference between their enthalpy value and that of Zhang et al (2004) (i.e.…”

“…In some cases, even when the protocol includes up to dozens of temperatures cycles, the systems might remain heterogeneous during the cooling phase (Sales Silva et al, 2016) and the water not completely converted to hydrates (Egenolf-Jonkmanns et al, 2017). Cyclopentane (CP) hydrates can form at atmospheric pressure at temperatures below ∼6−8 • C (Ho- Van et al, 2019). Owing to this very interesting property, CP hydrates are considered as a model system for various studies and applications.…”

Simultaneous Crystallization of Cyclopentane Hydrate and Sodium Chloride for Desalination and Salt Manufacture

“…2 The seawater desalination utilizing clathrate hydrates is a possible candidate for the optimum process and was extensively investigated in the last decade. 7,8 Clathrate hydrates, abbreviated hydrates hereafter, are icelike solid compounds formed by a reaction between water and guest compounds. 9 The water molecules comprise a cage-like structure and the guest molecules occupy it.…”

“…The hydrate-based seawater desalination technology utilizes the abovementioned characteristics. 7,8 When hydrates form by the reaction between seawater and a guest compound, water and the guest compound constitute the hydrates, whereas the electrolytes are concentrated in the remaining seawater. After the extraction of hydrates, freshwater could be obtained by hydrate decomposition, followed by the removal of the guest compound.…”

“…The requirements for guest compounds to be working media for hydrate-based seawater desalination are low solubility in water and low energy consumption for hydrate formation. Carbon dioxide, 10 hydrofluorocarbons, 11 and cyclopentane 8,10 are the representatives of the guest compounds for the hydrate-based seawater desalination that satisfy the abovementioned requirements. The disposal of wastewater is a serious problem, and improved wastewater management could generate social, environmental, and economic benefits essential for sustainable development.…”