Mechanism of hysteresis for composite multi-halide and its superior performance for low grade energy recovery

Abstract

Sorption hysteresis commonly exists for different sorbents and has a great impact on the performance, and recently it was found that the multi-halide sorbents could reduce the hysteresis phenomena. Here we report the mechanism of the sorption hysteresis for multi-halide under equilibrium/non-equilibrium conditions and its superior performance for low grade energy recovery. We find that the inner reaction among different halides does not happen and contribute to sorption hysteresis in sorption/desorption phases under equilibrium conditions. While under non-equilibrium conditions, multi-halide sorbents reduce the hysteresis significantly (the average hysteresis temperature difference decreases from 23.4 °C to 7.8 °C at 4.41 bar). The phenomena is studied, and results show that the continuous reaction within different halides under heterothermic condition leads to an operable multi-stage reaction property, which corresponds to better flexibility and faster response to heat source. The utilization of solar energy as heat source for a cloudy day is analyzed, and multi-halide sorbent has much larger average refrigeration power (improved by 43%) and could work efficiently most of the time. Such characteristics are also prospective for other thermochemical reaction technologies, such as de-NOx and energy storage because of lower energy input and higher energy output features.

Cold-heat adaptive control for cross-season based on bi-salt composite sorbent

“…CaCl 2 [12~14] , SrCl 2 [10] , SrBr 2 [15~17] , NaBr [18] , NiCl 2 [19] , MgCl [Mn(NH 3 ) 2 ]Cl 2 [26] , 不同的吸附剂其反应热力学和动 力学不尽相同, 因此研究者首先对金属卤化物-氨工质 对的吸附热力学和动力学展开了深入研究, 其中 Younes等人 [27] 首先综述了吸附剂-吸附质的平衡等温 吸附模型用来估算吸附量. 此后An等人 [28] 系统地总结 了金属卤化物-氨工质对的非平衡反应动力学模型, 并 且利用实验与仿真相结合的方法研究了MnCl 2 , CaCl 2 , NH 4 Cl [29] 和SrCl 2 [30] [32] . 而Alyousef等人 [33] ( )…”