Preparation and Performance Analysis of Modified Sodium Acetate Trihydrate

Abstract

In order to solve undercooling and phase separation of sodium acetate trihydrate (SAT), experimental screening method was used to select nucleating agents and thickeners that are suitable for SAT, and the optimal ratio was identified. Through screening experiments of nucleating agents, it is found that disodium hydrogen phosphate can be used as an effective nucleating agent for SAT. When the weight content of disodium hydrogen phosphate in SAT is 2%, the degree of undercooling was reduced to approximately 2 K. The addition of 1–1.5% (weight) of xanthan gum (XG) to SAT can effectively inhibit the phase separation. Since the properties of SAT changes after the modification, the corresponding comparison analysis was performed. The results showed that XG has a significant influence on the SAT performance of SAT. With the addition of 1.5 wt % of XG in pure SAT, the latent heat of fusion and solid/liquid volume expansion reduce by 5.2% and 5.4% respectively, and the thermal conductivity and solid/liquid density also decreases accordingly.

Nanocellulose-based composite phase change materials for thermal energy storage: status and challenges

“…Conventionally, synthetic polymers, such as poly (acrylamideco-acrylic acid) partial sodium salt, sodium polyacrylate, and polyvinyl alcohol, have been applied to address the phase separation issue of salt hydrate PCMs. [153][154][155][156] However, the non-sustainability and expensiveness limit their wide applications in energy storage applications. Although carboxyl methyl cellulose (CMC) as a cellulose derivative has been considered as the most prevailing thickening agent for preparing form-stable composite PCM slurries, developing more cost-effective substitutes remains warmly welcomed.…”

Preparation of Cellulose Nanofibrils/Salt Hydrate Composite Phase Change Materials for Thermal Energy Storage

“…Phase separation occurs due to the difference of densities of salt hydrate and water in the melting process, and this can be addressed by adding thickening agents such as polyacrylic amide, poly (acrylamide-co-acrylic acid) partial sodium salt, sodium polyacrylate, and polyvinyl alcohol [15][16][17][18]. These materials are soluble in aqueous phase, and increase the viscosity of salt hydrate solution so that flowing or precipitation of salt hydrate is hindered.…”

Preparation and Thermal Performance Analysis of New Composite Phase Change Materials of Sodium Acetate Trihydrate and Different Additives.

“…[19] Many scholars have conducted many studies on the supercooling of SAT, and the main method for suppressing this supercooling is the addition of hydrated salts or nanonucleating agents. Hua et al [20] added 1.5 wt% xanthan gum and 2 wt% DHPD to SAT and found that for the new composite of SAT/1.5 wt% XG/2 wt% DHPD, the supercooling degree was only 1.5 K, and the latent heat of phase change was 245.3 kJ/ kg. Wang et al [21] showed that the supercooling degree of SAT composited with 2 wt% Na 4 P 2 O 7 ⋅ 10H 2 O and 1.5 wt% polyacrylamide (PAM) was less than 5 °C.…”