TY - JOUR

T1 - Development of “salt in porous matrix” composites based on LiCl for sorption thermal energy storage

AU - Frazzica, A.

AU - Brancato, V.

AU - Caprì, A.

AU - Cannilla, C.

AU - Gordeeva, L. G.

AU - Aristov, Y. I.

N1 - Funding Information: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 764025 (SWS-HEATING). The Russian authors thank the budget project AAAA-A17-117041110045-9 of the Boreskov Institute of Catalysis for partial financial support. The authors acknowledge the support of Dr. Massimiliano Lo Faro (CNR-ITAE) for the XRD analysis performed. Funding Information: The EU-funded research project SWS-Heating [25] aims at the development of an innovative solar heating system based on sorption storage embedding a high density SWS. Starting from the reported literature review, this paper focuses on the performed activity for the preparation and characterization of optimal composite sorbents, based on LiCl and commercial mesoporous silica gels, aiming at the maximization of the salt content, according to well-defined boundary conditions under which the STES will operate. Particularly, two cost effective silica gels were identified and compared. Furthermore, also technical grade LiCl was used to reduce the overall cost of the final product. Two nominal salt quantities were investigated, namely, 30 wt% and 35 wt%, to identify the best solution. Dedicated characterizations were performed to verify the properties of the developed materials as well as to optimize the synthesis process in order to limit possible leakage effects. Finally, preliminary calculations of the achievable STES densities were performed to compare the results with other materials reported in the literature.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 764025 (SWS-HEATING). The Russian authors thank the budget project AAAA-A17-117041110045-9 of the Boreskov Institute of Catalysis for partial financial support. The authors acknowledge the support of Dr. Massimiliano Lo Faro (CNR-ITAE) for the XRD analysis performed. Publisher Copyright: © 2020 The Authors Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/10/1

Y1 - 2020/10/1

N2 - In this study, the development and characterization of composite sorbents based on commercial mesoporous silica gels and LiCl for seasonal thermal energy storage (STES) applications is described. The reported activity aims at validating the operation of sorption STES in various cold climatic zones in Europe. Accordingly, the reference boundary conditions were identified by means of a climatic analysis in two climatic zones, namely, Central and Northern Europe. The acquired mesoporous silica gels were characterized, to evaluate the textural properties, i.e. specific pore volume and pore size, needed to define the optimal salt solution compositions to maximize the amount of salt embedded. The synthesized samples were firstly investigated using scanning electron microscopy and nitrogen physisorption that demonstrate the presence of a small quantity of salt over the external surface rather than inside the pores. A hydrothermal treatment, based on slow adsorption followed by a slow desorption step, was defined to solve this issue. Finally, starting from the measured equilibrium isobars, the expected STES density at material level was evaluated, obtaining values as high as 1080 J/g under cold Northern European climatic condition, corresponding to 650 MJ/m3.

AB - In this study, the development and characterization of composite sorbents based on commercial mesoporous silica gels and LiCl for seasonal thermal energy storage (STES) applications is described. The reported activity aims at validating the operation of sorption STES in various cold climatic zones in Europe. Accordingly, the reference boundary conditions were identified by means of a climatic analysis in two climatic zones, namely, Central and Northern Europe. The acquired mesoporous silica gels were characterized, to evaluate the textural properties, i.e. specific pore volume and pore size, needed to define the optimal salt solution compositions to maximize the amount of salt embedded. The synthesized samples were firstly investigated using scanning electron microscopy and nitrogen physisorption that demonstrate the presence of a small quantity of salt over the external surface rather than inside the pores. A hydrothermal treatment, based on slow adsorption followed by a slow desorption step, was defined to solve this issue. Finally, starting from the measured equilibrium isobars, the expected STES density at material level was evaluated, obtaining values as high as 1080 J/g under cold Northern European climatic condition, corresponding to 650 MJ/m3.

KW - Adsorption

KW - Composite sorbent

KW - Solar energy

KW - Thermal energy storage

KW - DENSITY

KW - WATER-ADSORPTION

KW - SORBENTS

KW - HEAT TRANSFORMATION

KW - TECHNOECONOMIC ANALYSIS

KW - OF-THE-ART

UR - http://www.scopus.com/inward/record.url?scp=85087996661&partnerID=8YFLogxK

U2 - 10.1016/j.energy.2020.118338

DO - 10.1016/j.energy.2020.118338

M3 - Article

AN - SCOPUS:85087996661

VL - 208

JO - Energy

JF - Energy

SN - 0360-5442

M1 - 118338

ER -