Fabrication and heat storage properties of stearyl alcohol/expanded graphite composite phase change materials

doi:10.16085/j.issn.1000-6613.2020-0750

Abstract

Abstract:

The technology of phase change heat storage is one of the effective means to solve the heat imbalance in time and space. The development of high-performance composite phase change material (PCM) has become the focus of current researchers. At present, the low thermal conductivity and poor cyclic stability of stearyl alcohol(SAL) and other organic PCM limit their practical application. Herein, SAL was used as PCM and expanded graphite(EG) as porous matrix of high thermal conductivity. Sixteen kinds of SAL/EG composite PCMs (EG content was 7%, 14%, 21%, 28%(mass), sample density was 700kg/m³, 800kg/m³, 900kg/m³, 1000kg/m³) were prepared by adsorption form-stable process. The microstructure, thermal storage capacity, thermal conductivity, cycle stability and heat storage/release properties of the composite PCMs were studied and analyzed. The results show that SAL is completely filled in the porous network of EG. The horizontal thermal conductivity of the sample with sample density of 900kg/m³ and EG content of 28%(mass) is the highest, with a value as high as 28.58W/(m ? K), which is 74 times higher than pure SAL[0.38W/(m ? K)], which is about 4.8 times of the corresponding vertical thermal conductivity[5.99W/(m?K)]. In addition, the heat storage/release performance at the center of the sample was studied on the heat storage experiment system. The results show that the sample density is 900kg/m³ and the sample with the EG content of 28%(mass) has the maximum heat storage/release rate. The time of latent heat storage and release stages is 53minutes and 20minutes. At the same time, the thermal conductivity and melting-solidification characteristics of the samples are verified, which shows that SAL/EG composite PCMs has stable and reliable heat storage/release performance.

Key words: stearyl alcohol, expanded graphite, phase change material (PCM), thermal conductivity, heat storage capacity

摘要：

相变储热技术是解决热量在时空上分配不平衡问题的有效手段之一，研制高性能的复合相变材料（phase change material, PCM）成为当前研究者关注的重点。硬脂醇（stearyl alcohol, SAL）等有机PCM目前主要存在热导率偏低以及循环稳定性较差等问题而限制了实际应用。以SAL作为PCM，膨胀石墨（expanded graphite, EG）为高导热多孔基质，采用吸附定形工艺制备了16种SAL/EG复合PCMs[EG含量为7%、14%、21%、28%（质量）；样品密度为700kg/m³、800kg/m³、900kg/m³、1000kg/m³]。对复合PCMs样品的微观结构、储热能力、导热性能、循环稳定性及充放热性能进行研究与分析。结果表明：SAL完全填充于EG的多孔网络。当样品密度为900kg/m³，EG质量分数为28%的水平热导率最高，其值为28.58W/(m ? K)，相比于纯SAL[0.38W/(m ? K)]提高了74倍，该值大约是相对应垂直热导率[5.99W/(m ? K)]的4.8倍。另外在构建的充放热性能试验台上研究了样品中心位置的储/放热性能，结果显示样品密度为900kg/m³，EG质量分数为28%的样品充放热速率最大，固-液潜热吸热和放热阶段所经历的时间分别为53min和20min。与此同时验证了样品的导热性能和熔化-凝固特性，说明SAL/EG复合PCMs具有稳定可靠的储/放热性能。

关键词: 硬脂醇, 膨胀石墨, 相变材料, 导热性能, 储热能力

CLC Number:

TB332

KUAI Zihan, YAN Ting, WU Shaofei, ZHOU Yuxiang, PAN Weiguo. Fabrication and heat storage properties of stearyl alcohol/expanded graphite composite phase change materials[J]. Chemical Industry and Engineering Progress, 2021, 40(S1): 301-310.

蒯子函, 闫霆, 吴韶飞, 周宇翔, 潘卫国. 硬脂醇/膨胀石墨复合相变材料的制备及储热性能[J]. 化工进展, 2021, 40(S1): 301-310.

Figures/Tables 12

References 37

1	谢标. 复合相变材料储能及热控的理论和实验研究[D]. 合肥: 中国科学技术大学, 2016.
	XIE B. Theoretical and experimental study on energy storage and thermal control of composite phase change materials[D]. Hefei: University of Science and Technology of China, 2016.
2	FARAJ K, KHALED M, FARAJ J, et al. Phase change material thermal energy storage systems for cooling applications in buildings: a review[J]. Renewable and Sustainable Energy Reviews, 2020,119: 109579.
3	LAMIDI R O, JIANG L, PATHARE P B, et al. Recent advances in sustainable drying of agricultural produce: a review[J]. Applied Energy, 2019, 233/234: 367-385.
4	SHENG N, RAO Z, ZHU C, et al. Enhanced thermal performance of phase change material stabilized with textile-structured carbon scaffolds [J]. Solar Energy Materials and Solar Cells, 2020, 205: 110241.
5	WENG Y C, CHO P H, CHANG C C, et al. Heat pipe with PCM for electronic cooling[J]. Applied Energy, 2011, 88: 1825-1833.
6	BEHI H, GHANBARPOUR M, BEHI M. Investigation of PCM-assisted heat pipe for electronic cooling[J]. Applied Thermal Engineering, 2017, 127: 1132-1142.
7	郭启霖. 膨胀石墨/赤藓糖醇相变复合材料的制备与热性能研究[D]. 哈尔滨: 哈尔滨工业大学, 2015.
	GUO Q L. Preparation and thermal properties of expanded graphite/erythritol phase change composite[D]. Harbin: Harbin Institute of Technology, 2015.
8	于海涛. 硬脂酸/膨胀石墨相变储热材料的制备与应用[D]. 北京: 北京林业大学, 2016.
	YU H T. Preparation and application of stearic acid/expanded graphite phase change heat Storage material [D]. Beijing: Beijing Forestry University, 2016.
9	赵义清. 定形相变材料的制备及其定形效果的研究[D]. 上海: 复旦大学, 2011.
	ZHAO Y Q. Study on the preparation and shaping effect of shaped phase change materials [D]. Shanghai: Fudan University, 2011.
10	满亚辉. 相变潜热机制及其应用技术研究[D]. 长沙: 国防科学技术大学, 2010.
	MAN Y H. Study on latent heat mechanism of phase change and its application technology[D]. Changsha: National University of Defense Science and Technology, 2010.
11	QIAN T, LI J, MIN X, et al. Radial-like mesoporous silica sphere: a promising new candidate of supporting material for storage of low-, middle-, and high-temperature heat[J]. Energy, 2016, 112: 1074-1083.
12	JI R, WEI S, XIA Y, et al. Enhanced thermal performance of form-stable composite phase-change materials supported by novel porous carbon spheres for thermal energy storage[J]. Journal of Energy Storage, 2020, 27: 101134.
13	WANG J, HUANG X, GAO H, et al. Construction of CNT@Cr-MIL-101-NH₂ hybrid composite for shape-stabilized phase change materials with enhanced thermal conductivity[J]. Applied Thermal Engineering, 2018, 350: 164-172.
14	FENG D, FENG Y, QIU L, et al. Review on nanoporous composite phase change materials: fabrication, characterization, enhancement and molecular simulation[J]. Renewable and Sustainable Energy Reviews, 2019, 109:578-605.
15	JIN M Y, LIN Y, LIAO Y, et al. Development of highly-efficient ZIF-8@PDMS/PVDF nano-fibrous composite membrane for phenol removal in aqueous-aqueous membrane extractive process[J]. Journal of Membrane Science, 2018, 568: 121-133.
16	NUNTANG S, YOUSATIT S, YOKOI T, et al. Tunable mesoporosity and hydrophobicity of natural rubber/hexagonal mesoporous silica nano-composites[J]. Microporous and Mesoporous Materials, 2019, 275:235-224.
17	CHEN G, SHI T, ZHANG X, et al. Polyacrylonitrile/polyethylene glycol phase-change material fibres prepared with hybrid polymer blends and nano-SiC fillers via centrifugal spinning[J]. Polymer, 2019, 186: 122012.
18	张飞, 陶则超, 郭全贵. 压缩膨胀石墨/石蜡相变复合材料微观结构与强化传热研究[J]. 化工新型材料, 2016, 44(6): 135-137.
	ZHANG Fei, TAO Zechao, GUO Quangui. Microstructure and enhanced heat transfer of compression expanded graphite/paraffin phase change composite[J]. New Chemical Materials, 2016, 44(6): 135-137.
19	WU S F, YAN T, KUAI Z H, et al. Thermal conductivity enhancement on phase change materials for thermal energy storage: a review[J]. Energy Storage Materials, 2020, 25:251-295.
20	WU S, LI T, TONG Z, et al. High performance thermally conductive phase change composites by large size oriented graphite sheets for scalable thermal energy harvesting[J]. Advanced Materials, 2019,31(49): 1905099.
21	ZHAO Y, JIN L, ZOU B, et al. Expanded graphite-paraffin composite phase change materials: effect of particle size on the composite structure and properties[J]. Applied Thermal Engineering, 2020, 171: 115015.
22	ZHANG S, WU W, WANG S, et al. Experimental investigations of alum/expanded graphite composite phase change material for thermal energy storage and its compatibility with metals[J]. Energy, 2018, 161: 508-516.
23	TANG J, YANG M, YU F, et al. 1-octadecanol@hierarchical porous polymer composite as a novel shape-stability phase changematerial for latent heat thermal energy storage[J]. Applied Energy, 2017, 187: 514-522.
24	刘孟然, 王攀, 李建立, 等. 膨胀石墨基定型相变材料研究进展[J]. 化工新型材料, 2018, 46(12): 6-10.
	LIU Mengran, WANG Pan, LI Jianli, et al. Research progress of expanded graphite based phase change materials[J]. New Chemical Materials, 2018, 46(12): 6-10.
25	殷淑霞, 王琛, 雷圣宾, 等. 十八醇在石墨表面吸附组装结构的理论研究[J]. 电子显微学报, 2001, 20(5): 565-568.
	YIN Shuxia, WANG Chen, LEI Shengbin, et al. Theoretical study on the adsorption and assembly structure of n-octadecanol on graphite surface[J]. Journal of Chinese Electron Microscopy Society, 2001, 20(5): 565-568.
26	吴韶飞, 闫霆, 蒯子函,等. 高导热膨胀石墨/棕榈酸定形复合相变材料的制备及储热性能研究[J]. 化工学报, 2019,70(9): 3553-3564, 3207.
	WU Shaofei, YAN Ting, KUAI Zihan, et al. Study on the preparation and thermal storage properties of high thermal conductivity expanded graphite/palmitic acid form-stable composite phase change materials[J]. CIESC Journal, 2019, 70(9): 3553-3564, 3207.
27	翟天尧, 李廷贤, 仵斯, 等. 高导热膨胀石墨/硬脂酸定形相变储能复合材料的制备及储/放热特性[J]. 科学通报, 2018, 63(7): 674-683.
	ZHAI Tianyao, LI Tingxian, WU Si, et al. Preparation and heat storage/release characteristics of high thermal conductivity expanded graphite/stearic acid shaped phase change energy storage composite[J]. Chinese Science Bulletin, 2018, 63(7): 674-683.
28	KE H. Investigation of the effects of nano-graphite on morphological structure and thermal performances of fatty acid ternary eutectics/polyacrylonitrile/nano-graphite form-stable phase change composite fibrous membranes for thermal energy storage[J]. Solar Energy, 2018, 173: 1197-1206.
29	王涛. 环氧树脂包覆二十烷/膨胀石墨相变复合材料的制备与性能研究[D]. 哈尔滨: 哈尔滨工业大学, 2019.
	WANG T. Preparation and properties of eicosane/expanded graphite phase change composite coated with epoxy resin[D]. Harbin: Harbin Institute of Technology, 2019.
30	MHIKE W, FOCKE W W, MACKENZIE J, et al. Stearyl alcohol/palm triple pressed acid-graphite nanocomposites as phase change materials[J]. Thermochim Acta, 2018, 663: 77-84.
31	FU X, LIU Y, JIANG X, et al. Form-stable phase change nanocomposites for thermal energy storage based on hyper-crosslinked polymer nanospheres[J]. Thermochim Acta, 2018, 665: 111-118.
32	LV P, DING M, LIU C, et al. Experimental investigation on thermal properties and thermal performance enhancement of cctadecanol/expanded perlite form stable phase change materials for efficient thermal energy storage[J]. Renewable Energy, 2019, 131: 911-922.
33	TANG Y, LIN Y, JIA Y, et al. Improved thermal properties of stearyl alcohol/high density polyethylene/expanded graphite composite phase change materials for building thermal energy storage[J]. Energy Buildings, 2017, 153: 41-49.
34	袁维烨, 章学来, 华维三, 等. 膨胀石墨/三水乙酸钠复合相变材料储热的性能[J]. 化工进展, 2018, 37(11): 4405-4411.
	YUAN Weiye, ZHANG Xuelai, HUA Weisan, et al. Thermal storage performance of sodium acetate trihydrate/expanded graphite composite phase change material[J]. Chemical Industry and Engineering Progress, 2018, 37(11): 4405-4411.
35	顾庆军, 费华, 王林雅, 等. 癸酸-十六醇作为相变储能材料的相变特性[J]. 化工进展, 2019, 38(11):5033-5039.
	GU Qingjun, FEI Hua, WANG Linya, et al. Phase transition properties of capric acid-hexadecanol as phase change energy storage material[J]. Chemical Industry and Engineering Progress, 2019, 38(11):5033-5039.
36	李传常, 李琦, 姜竹, 等. 碳酸锂钠共晶盐复合相变材料的储放热特性[J]. 储能科学与技术, 2017(6):655-661.
	LI Chuanchang, LI Qi, JIANG Zhu, et al. Energy storage science and technology of lithium sodium carbonate eutectic composite phase change materials[J]. Energy Storage Science and Technology, 2017(6): 655-661.
37	孙婉纯, 冯锦新, 张正国, 等，相变储热技术用于被动式建筑节能的研究进展[J]. 化工进展, 2020, 39(5):1824-1834.
	SUN Wanchun, FENG Jinxin, ZHANG Zhengguo, et al. Research progress of phase change heat storage technology for passive energy conservation in buildings[J]. Chemical Industry and Engineering Progress, 2020, 39(5):1824-1834.

预设密度 /kg ? m^-3	实际密度/kg · m^-3
预设密度 /kg ? m^-3	7% EG	14% EG	21% EG	28% EG
700	698.36(A1)	697.95(B1)	695.83(C1)	704.16(D1)
800	796.18(A2)	800.89(B2)	799.78(C2)	796.09(D2)
900	898.20(A3)	897.16(B3)	899.89(C3)	898.21(D3)
1000	998.09(A4)	999.53(B4)	1000.03(C4)	999.83(D4)

预设密度 /kg ? m^-3	实际密度/kg · m^-3
预设密度 /kg ? m^-3	7% EG	14% EG	21% EG	28% EG
700	698.36(A1)	697.95(B1)	695.83(C1)	704.16(D1)
800	796.18(A2)	800.89(B2)	799.78(C2)	796.09(D2)
900	898.20(A3)	897.16(B3)	899.89(C3)	898.21(D3)
1000	998.09(A4)	999.53(B4)	1000.03(C4)	999.83(D4)

PCM	多孔支撑材料	制备方法	热导率/W ? m^-1 ? K^-1	潜热值/J ? g^-1	参考文献
硬脂醇+棕榈三压酸	10%（质量分数）石墨纳米板	混合加热搅拌	1.687	~158	［30］
硬脂醇	28.6%（质量分数）高交联聚合物纳米碳球	真空熔融，搅拌吸附	—	134.1	［31］
硬脂醇	膨胀珍珠石	真空浸渍法	6.623	140.2	［32］
硬脂醇	25%（质量分数）多孔聚合物	浸渍法	—	169.2	［23］
硬脂醇	聚乙烯+膨胀石墨	熔融吸附搅拌	0.6698	约200	［32］
硬脂醇	2%（质量分数）石墨烯	熔融混合，自组装法	0.37	202.8	［33］
硬脂醇	28%（质量分数）膨胀石墨	吸附定形	28.58	181.48	本工作

PCM	多孔支撑材料	制备方法	热导率/W ? m^-1 ? K^-1	潜热值/J ? g^-1	参考文献
硬脂醇+棕榈三压酸	10%（质量分数）石墨纳米板	混合加热搅拌	1.687	~158	［30］
硬脂醇	28.6%（质量分数）高交联聚合物纳米碳球	真空熔融，搅拌吸附	—	134.1	［31］
硬脂醇	膨胀珍珠石	真空浸渍法	6.623	140.2	［32］
硬脂醇	25%（质量分数）多孔聚合物	浸渍法	—	169.2	［23］
硬脂醇	聚乙烯+膨胀石墨	熔融吸附搅拌	0.6698	约200	［32］
硬脂醇	2%（质量分数）石墨烯	熔融混合，自组装法	0.37	202.8	［33］
硬脂醇	28%（质量分数）膨胀石墨	吸附定形	28.58	181.48	本工作

样品	固态显热吸热时间/min	固-液潜热吸热时间/min	液态显热吸热时间/min	液态显热放热时间/min	固-液潜热放热时间/min	固态显热放热时间/min
ρ=900kg ? m^-3，7% EG	43.5	56.5	37	9.5	34.5	44
ρ=900kg ? m^-3 14% EG	38	56	31.5	8.5	32.5	41.5
ρ=900kg ? m^-3 21% EG	33.5	55.2	21.5	9.5	30	40.5
ρ=900kg ? m^-3，28% EG	32.5	53	14	8	20	20.5