Investigation of the kinetics of TBAB + carbon dioxide semiclathrate hydrate in presence of tween 80 as a cold storage material

• Published in: Journal of molecular liquids Vol. 293; p. 111433
• Main Authors: Mohammadi, Abolfazl, Jodat, Amin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2019
• Subjects: Air conditioning; CO2; Cold storage; Kinetics; Semiclathrate hydrates; TBAB; Air conditioning; TBAB; Kinetics; Cold storage; Semiclathrate hydrates; CO2
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2019.111433

Because of large cold storage capacity and suitable freezing temperature of hydrate slurries, these materials could be used as a medium to store the cold energy in air conditioning systems. Semiclathrate hydrates of tetra n-butylammonium bromide (TBAB) are favorable phase change materials (PCMs), due to their moderate hydrate formation conditions. The kinetics of carbon dioxide - TBAB semiclathrate hydrate formation in presence and absence of tween 80 as a non-anionic surfactant is investigated in this research. The experiments were performed in a 169 cm3 stirred batch reactor at initial pressure of 3.2 MPa and isothermal condition of 276.15 K. Aqueous solutions of TBAB with concentrations of 0–15 wt% in presence and absence of tween 80 with concentrations of 500 and 1500 ppm are tested. The results revealed that utilization of TBAB with concentrations of 5–15 wt%, inhibits the kinetics of formed hydrates. By increasing the concentration of TBAB the amount and rate of gas uptake and storage capacity (SC) of formed hydrates decreases. Tween 80 with a concentration of 500 ppm presented a slight positive effect on the kinetics of hydrate formation in presence and absence of TBAB. While 1500 ppm of this additive inhibited the kinetics of formed hydrates. •CO2-TBAC semiclathrate hydrate was introduced as a cold storage medium.•The kinetics of CO2-TBAB semiclathrate hydrate was studied.•Storage capacity of CO2-TBAB semiclathrate hydrate was measured.•The effect of tween 80 on the kinetics of CO2-TBAB semiclathrate hydrate was studied.•Initial rate of CO2-TBAB semiclathrate hydrate formation was evaluated.