Enerji depolama uygulamaları için biyomakromolekül katkılı faz değiştiren madde kompozitlerin geliştirilmesi
Development of biomacromolecule-incorporated phase change material  composites for energy storage applications.
Yazar: BİLAL YILDIRIM
Danışman: PROF. DR. YELİZ KONUKLU ; DR. ÖĞR. ÜYESİ AYŞE
Niğde Ömer Halisdemir Üniversitesi / Fen Bilimleri Enstitüsü / Enerji Bilim ve Teknoloji Ana Bilim Dalı
Derece: Yüksek Lisans, 2024
Konu: Enerji = Energy

Özet:
Faz Değiştiren Maddeler (FDM), belirli bir sıcaklıkta faz değiştirerek (katı-sıvı veya sıvı- gaz) gizli ısıyı depolayıp veya serbest bırakan, böylece sıcaklık dalgalanmalarını önleyerek ısıl konfor sağlayan maddelerdir. Bu çalışmada termal enerji depolama uygulamalarında kullanılmak için bir biyomakromolekül olan hümik asit kullanılarak hümik asit katkılı faz değiştiren madde kompozitleri ve mikrokapsülleri geliştirilmiştir. Mikrokapsül işlemi esnasında oktadekan, parafin ve miristik asit kapsül çekirdek materyali ve hümik asit kapsüllerin dış duvar materyali olarak kullanılmıştır. Üretilen mikrokapsüllerin; erime donma özelliklerinin incelenmesi ve termal enerji depolama kapasitelerinin belirlenmesi amacıyla Diferansiyel Taramalı Kalorimetre (DSC) analizleri, termal stabilitelerini belirlemek amacıyla Termal Gravimetrik Analizleri (TGA), kimyasal özelliklerini belirlemek amacıyla Fourier Dönüşümlü Kızılötesi (FTIR) analizleri, morfolojik özelliklerinin belirlenmesi için Taramalı Elektron Mikroskobu (SEM) analizleri yapılmıştır. Ayrıca mikrokapsüllenmiş FDM'lerden oluşan peletlerin mekanik dayanım, termal iletkenlik ve termal performans özellikleri belirlenmiştir.

Abstract:
Phase change materials are substances that could change their physical forms within a certain temperature or pressure range. They cPhase change materials (PCMs) are substances that undergo a phase transition (solidliquid or liquid-gas) at a specific temperature, absorbing or releasing latent heat, thereby regulating temperature and enhancing thermal comfort. In this study, phase change material composites and microcapsules doped with humic acid, a biomacromolecule, were developed for use in thermal energy storage applications. During the microencapsulation process, octadecane, paraffine and myristic acid are used as the core material, and humic acid as the shell material of the capsules. The obtained microcapsules were analyzed for melting, freezing properties, and thermal energy storage capacity using differential scanning calorimetry (DSC). Thermal stability was determined through thermogravimetric analysis (TGA). Fourier-transform infrared spectroscopy (FTIR) was employed to assess chemical properties, while scanning electron microscopy (SEM) was used to examine morphological characteristics, Additionally, the mechanical strength, thermal conductivity, and thermal performance properties of pellets composed of microencapsulated PCMs were determinedan exist in solid, liquid, or gas form and can transition between these different forms. The phase transition of materials occurs through structural rearrangements at the molecular level. This study examines biopolymermodified phase change materials and microcapsules for energy storage applications to provide thermal management in thermal energy storage applications. During the microencapsulation process, octadecane, paraffine and myristic acid are used as the core, and humic acid as the shell of the capsules. The obtained microcapsules were analyzed for their leakage, melting, and freezing properties, and their thermal energy storage capacities were determined using differential scanning calorimetry (DSC) analyses, thermal stability was determined using thermal gravimetric analysis (TGA), chemical changes after long melting-freezing cycles were determined using Fourier-transform infrared spectroscopy (FTIR) analyses, scanning electron microscopy (SEM) analyses were conducted to determine morphological properties, and Brazilian tests were performed to determine tensile strength. Additionally, thermal conductivity analyses were conducted to determine the composite's heat conduction capability.