Na2S2O3·5H2O复合材料的制备及循环稳定性能  

Preparation and cyclic stability of Na2S2O3·5H2O composites

作　　者：张永一川 章学来[1] 徐笑锋 刘璐 ZHANG Yongyichuan;ZHANG Xuelai;XU Xiaofeng;LIU Lu(Institute of Cold Storage Technology,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]上海海事大学蓄冷技术研究所

出　　处：《化工进展》2019年第7期3304-3310,共7页Chemical Industry and Engineering Progress

摘　　要：为了解决Na2S2O3·5H2O存在的过冷度过大导致不结晶的问题,提高复合相变材料的循环稳定性并抑制相分离现象,以CaSO4和1-萘酚(C10H8O)为成核剂;聚丙烯酸钠(PAAS)和羧甲基纤维素钠(CMC)为增稠剂进行改良,通过步冷曲线和差示扫描量热法(DSC)对复合相变材料进行了研究。实验结果表明:加入质量分数为1%和5%的CaSO4、0.5%和3%的C10H8O对Na2S2O3·5H2O有较好的成核作用。萘酚体系在加入增稠剂后降温冷却时不出现结晶现象。对于CaSO4体系,增稠剂PAAS效果优于CMC,Na2S2O3·5H2O+1%CaSO4+2%PAAS复合材料相变温度47.7℃,相变潜热为200.4J/g;Na2S2O3·5H2O+5%CaSO4+2%PAAS复合材料相变温度48.2℃,相变潜热为213.4J/g;经过100次高低温循环后,1%CaSO4的复合材料相变温度47.6℃,相变潜热为192.4J/g,相较循环前相变潜热降低了3.99%。5%CaSO4的复合材料相变温度47.8℃,相变潜热211.2J/g,相比循环前下降1.03%。5% CaSO4体系较优于1% CaSO4体系,循环前后潜热值、相变温度变化不大,循环稳定性良好。This study is aimed to deal with the non-crystallization caused by condensate depression of Na2S2O3·5H2O,to improve the cycle stability of composite phase change materials,and to inhibit phase separation.In solving these problems,CaSO4 and 1-naphthol (C10H8O) are used as nucleating agents,and PAAS and CMC as thickeners.Composite phase change materials are analysed by the cooling curve and DSC.The experiments show that adding CaSO4 with mass fraction of 1% and 5% and C10H8O of 0.5% and 3% can help enormously in the nucleation of Na2S2O3·5H2O.When the thickeners are added,the naphthol system would not crystallize after cooling.For the CaSO4 system,the effect of the PAAS thickener is better than that of CMC.The phase transition temperature of Na2S2O3·5H2O+1%CaSO4+2%PAAS composite is 47.7℃,and the latent heat of phase change is 200.4J/g.The phase transition temperature of Na2S2O3·5H2O+5% CaSO4+2% PAAS composite is 48.2℃,and the latent heat of phase change is 213.4J/g.After high-low temperature cycle test,the phase transition temperature of 1% CaSO4 composite is 47.6℃,and the latent heat of phase change is 192.4J/g,which is decreased by 3.99% compared with the precirculation phase change.The phase transition temperature of the composite material of 5% CaSO4 is 47.8℃ and the latent heat of phase change is 211.2J/g,which is 1.03% lower than that before the cycle.The 5% CaSO4 system is better than the 1% CaSO4 system.The latent heat value and phase transition temperature change little before and after cycling,showing good cycling stability.

关 键 词：五水硫代硫酸钠 硫酸钙 1-萘酚 羧甲基纤维素钠 聚丙烯酸钠 循环稳定性 过冷度 相分离 

分 类 号：TK02[动力工程及工程热物理]