Yerel bitki özütlerinin biyodizel kristalleşme sıcaklıkları üzerindeki etkisinin Diferansiyel Taramalı Kalorimetri (DSC)ile incelenmesi

Year 2025, Volume: 45 Issue: 2, 136 - 148, 30.10.2025

Gediz Uğuz , Sevil Özkınalı , Selma Nacak , Nalan Türköz Karakullukçu , Sinem Kaya , Abdülvahap Çakmak

https://doi.org/10.47480/isibted.1526597

Abstract

Bu çalışmada, çeşitli bitki ekstraktlarının (Achillea millefolium L., Helichrysum arenarium L. Moench ve Rosa Canina L.) biyodizelin oksidatif kararlılığı üzerindeki doğal antioksidan etkinlikleri araştırılmıştır. Bitki ekstraktları Soxhlet yöntemi ile elde edilmiş ve biyodizel-dizel karışımları üzerindeki antioksidan aktiviteleri Yüksek Performanslı Sıvı Kromatografisi (HPLC) ve Fourier Dönüşümlü Kızılötesi Spektroskopisi (FT-IR) teknikleri ile değerlendirilmiştir. Achillea millefolium L.'nin FT-IR spektrumu, ekstrakt içerisinde ferulik asit, kafeik asit ve kumarik asit varlığını gösterirken, 2959 cm-1 ve 2923 cm-1'de tespit edilen C-H gerilme titreşimleri, ekstrakt içerisinde kateşin, taksifolin ve naringenin varlığını göstermiştir. Helichrysum arenarium L. Moench ve Rosa Canina L. IR Spectra'da kaempherol, naringenin, chrysin ve butein varlığı göstermiştir. 3000 ppm konsantrasyonlu bitki özleri, %20 biyodizel ve %80 dizelden oluşan biyodizel-dizel karışımlarına doğal antioksidanlar olarak eklendi. Karışım örnekleri D100, B20D80, B20D80A, B20D80H ve B20D80R olarak isimlendirilmiştir. Kristalleşme sıcaklıkları (Tcr), Diferansiyel Taramalı Kalorimetre (DSC) ile belirlenmiştir ve sonuçlar D100, B20D80, B20D80A, B20D803000H, B20D80R için kristalleşme başlangıç ​​sıcaklıklarının sırasıyla -7,71 °C, -8,07 °C, -8,16 °C, -8,34 °C ve -8,61 °C olduğunu gösterdi. Antioksidan içeren numunelerin Tcr değerleri, antioksidan içermeyen biyodizel numunesine (B20D80) kıyasla azalmıştır. Ayrıca, numunelerin termofiziksel özellikleri belirlenmiştir ve sonuçlar, temel yakıt özelliklerinin baz yakıt numunesine bitki özlerinin eklenmesiyle hafif etkilendiğini gösterdmiştir.

Keywords

Achillea millefolium L. , Helichrysum arenarium L. Moench , Rosa Canina , Biyodizel , Doğal Antioksidan , Kristallenme Sıcaklığı

Investigation of local plant extracts on biodiesel crystallization temperatures using Differential Scanning Calorimetry (DSC)

Abstract

In this study, the natural antioxidant efficiencies of various plant extracts (Achillea millefolium L., Helichrysum arenarium L. Moench, and Rosa Canina L.) on the oxidative stability of biodiesel were investigated. Plant extracts were obtained by Soxhlet method and their antioxidant activities on biodiesel-diesel blends were evaluated by High Performance Liquid Chromatography (HPLC) and Fourier Transform Infrared Spectroscopy (FT-IR) techniques. FT-IR spectrum of Achillea millefolium L., indicates the presence of ferulic acid, caffeic acid and coumaric acid in the extract and C-H stretching vibrations detected at 2959 cm-1 and 2923 cm-1 showed the presence of catechin, taxifolin and naringenin in the extract. Helichrysum arenarium L. Moench and Rosa Canina L. IR Spectra were shown the presence of kaempherol, naringenin, chrysin and butein. The plant extracts with 3000 ppm concentration were added to biodiesel-diesel blends consisting of 20% biodiesel and 80% diesel as natural antioxidants. The blend samples were coded as D100, B20D80, B20D80A, B20D80H and B20D80R. The crystallization temperatures (Tcr) were determined by Differential Scanning Calorimety (DSC) and the results show that the crystallization onset temperatures for D100, B20D80, B20D80A, B20D803000H, B20D80R were −7.71°C, −8.07°C, −8.16°C, −8.34°C and −8.61°C respectively. Tcr values of samples with antioxidant were decreased compared to the non-antioxidant biodiesel sample (B20D80). Additionally, the thermophysical properties of the samples were determined, and results showed that the basic fuel properties were slightly affected by the addition of plant extracts to the base fuel sample.

Keywords

Achillea millefolium L. , Biodiesel , Cyrstallisation temperature , Helichrysum arenarium L. Moench , Natural antioxidant , Rosa Canina

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