PREPARATION OF N-HEXADECANE/MONTMORILLONITE COMPOSITE PHASE CHANGE MATERIALS AND DETERMINATION OF ITS PROPERTIES

Öz

Phase change materials (PCMs) are important functional materials that allow heat to be stored as a latent heat at a constant temperature during phase change and to be released into the environment as when needed. Within phase change materials classified as organic, inorganic and eutectic according to the chemical composition, paraffins in the class of organic phase change materials are highly remarkable materials for use in thermal energy storage applications due to their high latent heat storage capacities, good phase change performance, and with possessed thermal and chemical stability. On the other hand, micro- or macro-sized encapsulation is required due to the large volume changes and possible leakage problems of these materials during phase change period. Furthermore, it is possible to increase the structural, chemical and thermal stability of these materials with nano fillers of various structures. In this study, n-hexadecane / modified montmorillonite composite phase change materials were prepared by phase inversion emulsification method. For this purpose, n-hexadecane as the phase change material was encapsulated in micro-size in the poly(styrene-co-divinylbenzene) copolymer shell in the presence of surface modified montmorillonite (MMT) clay, which was added to the emulsion system at different loading amounts. Thermal, morphological and structural properties of microcapsules were investigated. The results of the analysis showed that the obtained composite materials are the potential candidates for the storage of energy in heating and cooling systems operated at low temperature (18-30˚C) on account of their thermal energy storage capacities and suitable phase change temperatures as well as their high thermal stability. 

Anahtar Kelimeler

• Energy,Thermal Energy Storage,Phase Change Material,Microencapsulation,Thermal Analysis

N-HEKZADEKAN/MONTMORİLLONİT KOMPOZİT FAZ DEĞİŞTİREN MADDELERİN HAZIRLANMASI VE ÖZELLİKLERİNİN BELİRLENMESİ

Öz

Faz değiştiren maddeler (FDMler), ısıl enerjinin faz değişimi esnasında sabit sıcaklıkta gizli ısı olarak depolanmasına ve gerektiğinde ortama salınmasına izin veren önemli fonksiyonel malzemelerdir. Kimyasal bileşimine göre organik, inorganik ve ötektik olmak üzere sınıflandırılan faz değiştiren maddelerden organik faz değiştiren maddeler sınıfında yer alan parafinler, yüksek gizli ısı depolama kapasiteleri, iyi faz değişim performansları, ısıl ve kimyasal kararlılıklarıyla ısıl enerji depolama uygulamalarında kullanım amacıyla oldukça dikkat çeken malzemelerdir. Ancak, bu malzemelerin faz değişimi esnasında gösterdikleri büyük hacim değişimi ve muhtemel sızdırma probleminden ötürü mikro ya da makro boyutta kapsülasyon işlemine gerek duyulmaktadır. Bunun yanı sıra, çeşitli yapıda nano dolgularla bu malzemelerin yapısal, kimyasal ve ısıl olarak kararlılıklarının arttırılması da mümkündür. Bu çalışmada, n-hekzadekan/modifiye montmorillonit kompozit faz değiştiren maddeler faz inversiyon emülsifikasyonu yöntemiyle hazırlanmıştır. Bu amaçla, faz değiştiren madde olarak n-hekzadekan, farklı katkı oranlarında emülsiyon sistemine ilave edilen, yüzey modifiye montmorillonit (MMT) kili varlığında poli(stiren-ko-divinilbenzen) kopolimer kabuk içerisinde mikro boyutta kapsüllenmiştir. Hazırlanan mikrokapsüllerin ısıl, morfolojik ve yapısal özellikleri incelenmiştir. Analiz sonuçları, elde edilen kompozit malzemelerin sahip oldukları ısıl enerji depolama kapasiteleri ve uygun faz değişim sıcaklıkları yanında yüksek ısıl kararlılıklarıyla düşük sıcaklıktaki (18-30˚C) ısıtma ve soğutma sistemlerinde enerji depolanması amacıyla kullanılabilecek potansiyel birer aday olduğunu göstermiştir. 

Anahtar Kelimeler

• Enerji,Termal Analiz,Isıl Enerji Depolama,Faz Değiştiren Maddeler,Mikrokapsülasyon,Mikrokapsülasyon

Kaynakça

1. Alay, S., Göde, F., Alkan, C., 2009. Isıl Enerji Depolama için Poli(etil akrilat)/Hekzadekan Mikrokapsüllerinin Üretilmesi ve Karakterizasyonu. Tektil Teknolojileri Elektronik Dergisi, 3 (3), 33-46.
2. Alexandre, M., Dubois, P., 2000. Polymer-Layered Silicate Nanocomposites: Preparation, Properties And Uses Of New Class of Materials. Materials Science and Engineering, 28, 1-63.
3. Alic, B., Sebenik, U., Krajnc, M., 2012. Microencapsulation of Butyl Stearate with Melamine-Formaldehyde Resin: Effect of Decreasing the pH Value on the Composition and Thermal Stability of Microcapsules. Express Polymer Letters, 6, 826-836.
4. Alkan, C., Sarı, A., Karaipekli, A., Uzun, O., 2009. Preparation, Characterization, and Thermal Properties of Microencapsulated Phase Change Material for Thermal Energy Storage. Solar Energy Materials & Solar Cells, 93, 143-147.
5. Alkan, C., Sarı, A., Karaipekli, A., 2011. Preparation, Thermal Properties and Thermal Reliability of Microencapsulated N-Eicosane as Novel Phase Change Material For Thermal Energy Storage. Energy Conversion and Management, 52, 687-692.
6. Borreguero, A.M., Carmona, M., Luz, M., Sanchez, L., Valverde , J.L., Rodriguez, J.F., 2010. Improvement of the Thermal Behaviour of Gypsum Blocks By the Incorporation of Microcapsules Containing PCMs Obtained By Suspension Polymerization with an Optimal Core/Coating Mass Ratio. Applied Thermal Engineering, 30, 1164-1169.
7. Chen C., Liu X., Liu W., Ma M., 2014. A Comparative Study of Myristic Acid/Bentonite and Myristic Acid/Eudragit L100 Form Stable Phase Change Materials for Thermal Energy Storage. Solar Energy Materials and Solar Cells, 127,14–20.
8. Chen M., Zheng S., Wu S., Xu G., 2010. Melting Intercalation Method to Prepare Lauric Acid/Organophilic Montmorillonite Shape-Stabilized Phase Change Material. Journal of Wuhan University of Technology-Material Science and Edition, 25, 674–677.

9. Gao G. B., Qian C. X., Gao M. J., 2010. Preparation and Characterization of Hexadecane Microcapsule with Polyurea-Melanine Formaldehyde Resin Shell Materials. Chinese Chemical Letters, 21, 533-537.
10. Gondora W., Doudin K., Nowakowski D. J., Xiao B., Ding Y., Bridgwater T., Yuan Q., 2016. Encapsulation of Phase Change Materials Using Rice-Husk-Char. Applied Energy, 182, 274-281.
11. Fan, L.W., Fang, X., Wang, X., Zeng, Y., Xiao, Y.Q., Yu, Z.T., Xu, X., Hu, Y.C., 2013. Effects of Various Carbon Nanofillers on the Thermal Conductivity and Energy Storage Properties of Paraffin-Based Nanocomposite Phase Change Materials. Applied Energy, 110, 163-172.
12. Fang, G., Li, H., Chen, Z., Liu, X., 2010. Preparation and Characterization of Flame Retardant N-Hexadecane/Silicon Dioxide Composites as Thermal Energy Storage Materials. Journal of Hazardous Materials 181, 1004-1009.
13. Feng, L., Zheng, J., Yang, H., Guo, Y., Li, W., Li, X., 2011. Preparation and Characterization of Polyethylene Glycol/Active Carbon Composites as Shape-Stabilized Phase Change Materials. Solar Energy Materials & Solar Cells, 95, 644-650.
14. Hawlader, M.N.A., Uddin, M.S., Khin, M.M., 2003. Microencapsulated PCM Thermal Energy Storage System. Applied Energy,74, 195-202.
15. Jeong S-G, Jin Chang S., We S., Kim S., 2015. Energy Efficient Thermal Storage Montmorillonite with Phase Change Material Containing Exfoliated Graphite Nanoplatelets. Solar Energy Materials and Solar Cells, 139, 65–70.
16. Khadiran, T., Hussein, M.Z., Zainal, Z., Rusli, R., 2015. Shape-stabilised N-Octadecane/Activated Carbon Nanocomposite Phase Change Material for Thermal Energy Storage. Journal of the Taiwan Institute of Chemical Engineers, 55, 189-197.
17. Kim, S., Chang, S.J., Chung, O., Jeong, S. G., Kim, S., 2014. Thermal Characteristics of Mortar Containing Hexadecane/XGNP SSPCM and Energy Storage Behaviors of Envelopes Integrated with Enhanced Heat Storage Composites for Energy Efficient Buildings. Energy and Buildings, 70, 472-479.
18. Konuklu, Y., Paksoy, H.O., Ünal, M., 2015. Nanoencapsulation of N-Alkanes with Poly(Styrene-Co-Ethylacrylate) Shells for Thermal Energy Storage. Applied Energy, 150, 335-340.
19. Konuklu, Y., Paksoy, H.Ö., 2017. Polystyrene Based Caprylic Acid Microencapsulation for Thermal Energy Storage. Solar Energy Materials & Solar Cells, 159, 235-242.
20. Lashgari S., Arabi H., Mahdavian A. R., Ambrogi V., 2017. Thermal and Morphological Studies on Novel PCM Microcapsules Containing N-Hexadecane as the Core in a Flexible Shell. Applied Energy, 190, 612-622.
21. Lee, S.H., Yoon, S.J., Kim, Y.G., Choi, Y.C., Kim, J.H., Lee, J.G., 2007. Development of Building Materials by Using Micro-Encapsulated Phase Change Material. Korean Journal of Chemical Engineering, 24, 332-335.
22. Li, M., Wu, Z., 2013. Thermal Properties of the Graphite/N-Docosane Composite PCM. Journal of Thermal Analysis and Calorimetry, 111, 77-83.
23. Li, M., Guo, Q., Nutt, S., 2017. Carbon Nanotube/Paraffin/Montmorillonite Composite Phase Change Material for Thermal Energy Storage. Solar Energy, 146, 1-7.
24. Liu, L., Su, D., Tang, Y., Fang, G., 2016. Thermal Conductivity Enhancement of Phase Change Materials For Thermal Energy Storage: A Review. Renewable and Sustainable Energy Reviews 62, 305–317.
25. Lv, P., Liu, C., Rao, Z., 2017. Review on Clay Mineral-Based Form-Stable Phase Change Materials:Preparation, Characterization And Applications. Renewable and Sustainable Energy Reviews 68, 707–726.
26. Ma, S., Song, G., Li, W., Fan, P., Tang, G., 2010. UV Irradiation-Initiated MMA Polymerization to Prepare Microcapsules Containing Phase Change Paraffin. Solar Energy Materials & Solar Cells, 94, 1643-1647.
27. Mert, M.S., Sert, M., Mert, H.H., 2018. Isıl Enerji Depolama Sistemleri İçin Organik Faz Değiştiren Maddelerin Mevcut Durumu Üzerine Bir İnceleme. Mühendislik Bilimleri ve Tasarım Dergisi, 6(1), 161-174.
28. Mert, M.S., Mert, H.H., Sert, M., 2019a. Microencapsulated Oleic–Capric Acid/Hexadecane Mixture As Phase Change Material For Thermal Energy Storage. Journal of Thermal Analysis and Calorimetry, 2019, 136, 1551-1561.
29. Mert, M.S., Mert, H.H., Sert, M., 2019b. Investigation of Thermal Energy Storage Properties of A Microencapsulated Phase Change Material Using Response Surface Experimental Design Methodology. Applied Thermal Engineering, 149, 401-413.
30. Özonur, Y., Mazman, M., Paksoy, H. Ö, Evliya, H., 2006. Microencapsulation of Coco Fatty Acid Mixture for Thermal Energy Storage with Phase Change Material. International Journal of Energy Research, 30(10), 741-749.
31. Peng K., Fu L., Li X., Ouyanga J., Yang H., 2017. Stearic Acid Modified Montmorillonite as Emerging Microcapsules for Thermal Energy Storage. Applied Clay Science, 138,100–106.
32. Sami S., Etesami N., 2017. Thermal Characterization of Obtained Microencapsulated Paraffin Under Optimal Conditions for Thermal Energy Storage. Journal of Thermal Analysis and Calorimetry, 130,1961–1971.
33. Sanchez L., Rodriguez, J.F., Romero, A., Borreguero, A.M., Carmona, M., Sanche, P., 2010. Microencapsulation of PCM with a Styrene-Methyl Methacrylate Copolymer Shell By Suspension-Like Polymerization. Chemical Engineering Journal, 157, 216-222.
34. Sanchez, L., Sanchez, P., Lucas, A.D., Carmona, M., Rodriguez, J.F., 2007. Microencapsulation of PCMs with a Polystyrene Shell. Colloid and Polymer Science, 285 (12), 1377-1385.
35. Sanchez, L., Rodriguez, J.F., Carmona, M., Romero, A., Sanchez, P., 2011. Thermal and Morphological Stability of Polystyrene Microcapsules Containing Phase-Change Materials. Journal of Applied Polymer Science, 120, 291-297.
36. Sarı, A., Alkan, C., Karaipekli, A., Uzun, O., 2009. Microencapsulated N-Octacosane as Phase Change Material For Thermal Energy Storage. Solar Energy Materials & Solar Cells, 83(10), 1757-1763.
37. Sarı, A., Alkan, C., Karaipekli, A., 2010. Preparation, Characterization and Thermal Properties Of PMMA/N-Heptadecane Microcapsules as Novel Solid-Liquid Micropcm for Thermal Energy Storage. Applied Energy, 87, 1529-1534.
38. Sarı, A., Alkan, C., Altıntaş, A., 2014a. Preparation, Characterization and Latent Heat Thermal Energy Storage Properties of Micro-Nanoencapsulated Fatty Acids By Polystyrene Shell. Applied Thermal Engineering, 73, 1160-1168.
39. Sarı, A., Alkan, C., Döğüşcü, D.K., Biçer, A., 2014b. Micro/nano-encapsulated N-Heptadecane with Polystyrene Shell for Latent Heat Thermal Energy Storage. Solar Energy Materials & Solar Cells, 126, 42-50.
40. Sarı A., Alkan C., Biçer A., Bilgin C., 2014c. Latent Heat Energy Storage Characteristics of Building Composites Of Bentonite Clay And Pumice Sand With Different Organic PCMS. International Journal of Energy Research, 38, 1478–1491.
41. Sarıer N., Onder E., 2007. Thermal Characteristics of Polyurethane Foams Incorparated with Phase Change Materials. Thermochimica Acta, 454, 90-98.
42. Park, S.J., Kim, K.S., Hong, S.K., 2005. Preparation and Thermal Properties of Polystyrene Nanoparticles Containing Phase Change Materials as Thermal Storage Medium. Polymer Korea, 29(1),8-13.
43. Wang Y., Zheng H., Feng H.X, Zhang D.Y., 2012. Effect of Preparation Methods on the Structure and Thermal Properties of Stearic Acid/Activated Montmorillonite Phase Change Materials. Energy and Buildings, 47,467–473.
44. Yang, R., Xu, H., Zhang, Y., 2003. Preparation, Physical Property and Thermal Physical Property of Phase Change Microcapsule Slurry and Phase Change Emulsion. Solar Energy Materials & Solar Cells, 80(4),405-416.
45. Zhao, C.Y., Wu, Z.G., 2011. Heat Transfer Enhancement of High Temperature Thermal Energy Storage Using Metal Foams and Expanded Graphite. Solar Energy Materials & Solar Cells, 95, 636-643.
46. Zhao, C.Y., Zhang G.H., 2011. Review on Microencapsulated Phase Change Materials (MEPCMS):Fabrication, Characterization and Applications. Renewable and Sustainable Energy Reviews, 15, 3813-3832.
47. Zhou, D., Zhao, C.Y., 2011. Experimental Investigations on Heat Transfer in Phase Change Materials (PCM)s Embedded İn Porous Materials. Applied Thermal Engineering, 31, 970-977.