Yazar "Aydemir, Deniz" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    Lignin activated carbon obtained by a environmentally friendly green production process using deep eutectic solvents
    (Wiley, 2024) Aydemir, Deniz; Ergun, Mehmet Emin; Gulsoy, Sezgin Koray; Ozan, Zeynep Eda; Gunduz, Gokhan
    The aim of this study was to produce activated carbon (AC) from lignin obtained with deep eutectic solvents (DESs) of choline chloride-lactic acid. For this, lignin particles were produced using the DES. The DES lignin (DES-Lig) was modified with zinc dichloride, and the lignin activated carbon (lig-AC) was produced by carbonization at 600 and 900 degrees C. In this study, the AC obtained from the commercial lignin was also used to determine the changes in the lig-AC from the lignin obtained with the DES. The material properties were investigated using Brunauer-Emmett-Teller (BET) surface analysis, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), and the structural properties were investigated with X-ray diffractometry (XRD) of the lig-ACs. The commercial and DES-Lig exhibited different microscopic morphologies. The surface area of the samples generally ranged from 504 to 698 g/cm2, and they included both micro- and mesopores according to SEM characterization. The XRD analysis showed that the ACs obtained have an amorphous structure, and thermogravimetric analysis of the ACs exhibited similar thermal behavior to that in the literature. The best morphological structure was found in the ACs prepared from lignin with the DES at 900 degrees C according to the results of SEM, TGA, XRD and BET analysis. The proximate analysis showed that the best ACs contain 1.5% moisture, 6.5% volatile matter, 5.5% ash content and 86.5% fixed carbon. According to the elemental analysis, the amounts of essential elements, including C, H, N and O were investigated, and the best activated carbon was determined to be the DES-Lig at 900 degrees C according to BET and the proximate fixed carbon results.
  • [ X ]
    Öğe
    The Effect of Foamed Urea-Formaldehyde Adhesive on Physical and Mechanical Properties of Medium Density Fiberboards (MDF)
    (Zagreb Univ, Fac Forestry, 2024) Ozlusoylu, Ismail; Stek, Abdullah, I; Ergun, Mehmet Emin; Aydemir, Deniz
    center dot In this study, the effect of using foamed urea-formaldehyde (UF) adhesive in the production of medium-density fiberboard (MDF) on the properties of the board was investigated. A commercial foaming agent was used to increase the volume of UF adhesive by approximately 2.5 times. MDFs were produced using 6, 9 and 12 % adhesive and1 % ammonium chloride hardener relative to the dry weight of the adhesive. The thermal degradation behavior of the foamed and control adhesives was determined by thermal analysis i.e., thermogravimetric (TGA) and derivative thermogravimetric (DTG) analyses. It was found that the foaming agent did not affect the thermal degradation of the adhesive. Scanning electron microscope images showed that the volume of foamed adhesive and blending efficiency increased. It was determined that MDFs produced with foamed adhesive had better water absorption and thickness swelling properties than control boards. However, the internal bond strength (IB) and modulus of elasticity (MOE) were found to be 8-14 % and 3-16 % higher, respectively, compared to the control samples. As a result, it can be concluded that the foaming process had a positive effect on the board properties and had the potential to reduce the amount of adhesive used.