Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Search Results

Now showing 1 - 3 of 3
  • Article
    Citation - Scopus: 8
    Biofuel Production From Nannochloropsis Oculata Microalgae in Seawater Without Harvesting and Dewatering Over Alumina-Silicate Supported Nickel Catalysts
    (Elsevier, 2018) Deliismail, Özgün; Özdoğru, Bertan; Şeker, Erol
    The aim of this work was to study the production of biofuels from marine Nannochloropsis oculata without harvesting and dewatering over the single step sol-gel made alumina-silicate supported nickel catalysts at 80 °C and 1.0 atm. Sulfuric acid, hydrochloric acid, and nitric acid were used in the sol-gel to study the effect of acid type on catalyst activities. The catalyst made using sulfuric acid resulted in 74% microalgae conversion as compared to the catalysts made with other acids. Treatment of this catalyst with ~35 g of NaCl per kg of water at 80 °C and 1.0 atm for 24 h increased microalgae conversion to 91.5% under the same reaction condition and the bio-fuels ranging from mono/polysaccharides, polyols to esters and fatty acids were produced. This study showed that nickel and 25.1 ?mol/g of total acidity and acidic strength having 130–380 °C of temperature range was necessary to achieve 91.5% conversion. © 2018 Elsevier Ltd
  • Article
    Citation - WoS: 12
    Citation - Scopus: 16
    Carotenoid Profile in Prochlorococcus Sp. and Enrichment of Lutein Using Different Nitrogen Sources
    (Springer Verlag, 2016) Erdoğan, Ayşegül; Demirel, Zeliha; Eroğlu, Ahmet Emin; Conk Dalay, Meltem
    Various carotenoids of the cyanobacterium Prochlorococcus sp. are identified using chromatographic/spectroscopic techniques and quantified using HPLC-DAD. In the present study, β-apo-8′-carotenal was used as internal standard. Identification of carotenoids was carried out by comparing the retention time, absorption spectra, and mass spectra of unknown peaks with reference standards. All-trans-lutein was found to be the major carotenoid in this cyanobacterium, and, therefore, algal productivity and the potential for lutein accumulation were analyzed as a function of different nitrogen sources such as nitrate, nitrite, ammonia, and urea for cultivation. Among them, urea clearly led to the best lutein accumulation. According to the experimental evidence, lutein increased from 2.54 to 3.34 mg g−1 in the cyanobacteria when urea was used as the nitrogen source. © 2016, Springer Science+Business Media Dordrecht.
  • Article
    Citation - WoS: 273
    Citation - Scopus: 327
    Transesterification of Nannochloropsis Oculata Microalga's Lipid To Biodiesel on Al2o3 Supported Cao and Mgo Catalysts
    (Elsevier Ltd., 2009) Umdu, Emin Selahattin; Tuncer, Mert; Şeker, Erol
    In this study, we present the activities of Al2O3 supported CaO and MgO catalysts in the transesterification of lipid of yellow green microalgae, Nannochloropsis oculata, as a function of methanol amount and the CaO and MgO loadings at 50 °C. We found that pure CaO and MgO were not active and CaO/Al2O3 catalyst among all the mixed oxide catalysts showed the highest activity. Not only the basic site density but also the basic strength is important to achieve the high biodiesel yield. Biodiesel yield over 80 wt.% CaO/Al2O3 catalyst increased to 97.5% from 23% when methanol/lipid molar ratio was 30.