Huseyin Kara

New options for conversion of vegetable oils to alternative fuels

Biodiesel from transesterification of vegetable oils is an excellent alternative fuel. There is, however, a need to develop a direct process for conversion of vegetable oils into gasoline-competitive biodiesel and other petroleum products. Methyl esters of vegetable oils have several outstanding advantages among other new-renewable and clean engine fuel alternatives. The purpose of the transesterification process is to lower the viscosity of vegetable oil. Compared to No. 2 diesel fuel, all of the vegetable oils are much more viscous, whereas methyl esters of vegetable oils are slightly more viscous. The methyl esters are more volatile than those of the vegetable oils. Conversion of vegetable oils to useful fuels involves the pyrolysis and catalytic cracking of the oils into lower molecular products. Pyrolysis produces more biogasoline than biodiesel fuel. Soap pyrolysis products of vegetable oils can be used as alternative diesel engine fuel. The soaps obtained from the vegetable oils can be pyrolyzed into hydrocarbon-rich products. Zinc chloride catalyst contributed greatly to high amounts of hydrocarbons in the liquid product. The yield of ZnCl 2 catalytic conversion of the soybean oil reached the maximum 79.9% at 660 K.

Synthesis of p‐tert‐Butylcalix[4]arene Dinitrile Bonded Aminopropyl Silica and Investigating Its Usability as a Stationary Phase in HPLC

The chromatic separation of adenine, adenosine, cytosine, phenol, benzene, and toluene were investigated by using 5,11,17,23‐tert‐butyl‐25,27‐bis(cyanomethoxy)‐26‐(chloroformyl)‐28‐hydroxy‐calix[4]arene bonded aminopropyl silica (CDBAPS) as a stationary phase. The separation ability of the stationary phase was observed to be good for target species. The effect of non‐polar calix[n]arene network was observed in chromatographic processes, and it was thought that, thanks to the relatively polar nitrile groups, further selectivity would be obtained in various chromatographic separations.

Towards multimodal HPLC separations on humic acid-bonded aminopropyl silica: RPLC and LEC behavior

In the present study, metal binding property of humic acid (HA) was successfully adapted to the ligand-exchange concept, and metal-loaded immobilized humic acid was used as a ligand exchanger stationary phase for separation of some nucleosides. Humic-acid bonded aminopropyl silica (EC-HA-APS) was turned into ligand exchanger forms by loading aqueous solutions of Cu(2+), and Co(2+) to the column (4.6 × 150; as mm) packed with EC-HA-APS. Metal ion solutions were loaded to the column in a stepwise manner where the concentration of metal ion solution being loaded to the column was increased gradually between 5 and 100mM. The progress of metal loading process was monitored via the breakthrough curves propagated stepwise. Ligand-exchange chromatography (LEC) studies were performed on an HPLC system, and chromatographic behaviors of the studied nucleosides (i.e. uridine, Urd; thymidine, Tyd; cytidine, Cyd; adenosine, Ado; and guanosine, Guo) were investigated on Cu(2+) and Co(2+) loaded forms of the EC-HA-APS (Cu-EC-HA-APS and Co-EC-HA-APS). Effect of mobile phase composition, temperature, and the type of metal ion loaded to the column on the retentive behaviors of the compounds was studied, in detail. The studied solutes exhibited mixed-mode RPLC/LEC behavior on the stationary phase. Metal-loaded column (M-EC-HA-APS) was easily regenerated into its original form, EC-HA-APS, with 98 ± 2% metal recoveries, by using aqueous mixture of EDTA+NH(3) at pH=7.5. Thus, the stationary phase exhibited a high flexibility between RPLC and LEC modes. This property, also, made it possible to convert the stationary phase into various ligand exchanger forms by loading different metal ions. Hence, capacity and selectivity of the stationary phase towards the studied species was manipulated easily by loading different metal ions to the stationary phase. Baseline separation for the studied species was achieved on Cu-EC-HA-APS and Co-EC-HA-APS and some differentiations were observed in capacity and selectivity, depending on the type of metal loaded. Thus, being as the first endeavor on usability of immobilized HA as a ligand exchanger stationary phase, the present study is believed to be useful to understand multifunctional character of HA-based solid/stationary phases.

Evaluation of Fatty Acid Composition, Tocols Profile, and Oxidative Stability of Some Fully Refined Edible Oils

Present study includes evaluation of fatty acid composition, tocols profile, and oxidative stability of some fully refined edible oils. Fully refined sunflower, soybean, corn, hazelnut, peanut, and canola oils were analyzed for fatty acids by capillary gas liquid chromatography, tocols by normal phase-high performance liquid chromatography and oxidative stability by rancimat. Free fatty acid, peroxide value, and iodine value of investigated oils were determined by titrimetric methods. Saturated, mono-, and polyunsaturated fatty acids were found to be in the ranges between 2.03–18.58, 23.39–77.26, and 14.39–58.52%, respectively. Tocols and oxidative stability of the investigated oils were found to be in the ranges between 488.88–913.51 mg kg−1 and 3.05–4.99 h, respectively.

Application of multivariate chemometric techniques for simultaneous determination of five parameters of cottonseed oil by single bounce attenuated total reflectance Fourier transform infrared spectroscopy

Single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopy in conjunction with chemometrics was used for accurate determination of free fatty acid (FFA), peroxide value (PV), iodine value (IV), conjugated diene (CD) and conjugated triene (CT) of cottonseed oil (CSO) during potato chips frying. Partial least square (PLS), stepwise multiple linear regression (SMLR), principal component regression (PCR) and simple Beer׳s law (SBL) were applied to develop the calibrations for simultaneous evaluation of five stated parameters of cottonseed oil (CSO) during frying of French frozen potato chips at 170°C. Good regression coefficients (R(2)) were achieved for FFA, PV, IV, CD and CT with value of >0.992 by PLS, SMLR, PCR, and SBL. Root mean square error of prediction (RMSEP) was found to be less than 1.95% for all determinations. Result of the study indicated that SB-ATR FTIR in combination with multivariate chemometrics could be used for accurate and simultaneous determination of different parameters during the frying process without using any toxic organic solvent.

A simplified FTIR chemometric method for simultaneous determination of four oxidation parameters of frying canola oil

Transmission Fourier transform infrared (FTIR) spectroscopic method using 100 μm KCl cell was applied for the determination of total polar compounds (TPC), carbonyl value (CV), conjugated diene (CD) and conjugated triene (CT) in canola oil (CLO) during potato chips frying at 180 °C. The calibration models were developed for TPC, CV, CD and CT using partial least square (PLS) chemometric technique. Excellent regression coefficients (R(2)) and root mean square error of prediction values for TPC, CV, CD and CT were found to be 0.999, 0.992, 0.998 and 0.999 and 0.809, 0.690, 1.26 and 0.735, respectively. The developed calibration models were applied on samples of canola oil drawn during potato chips frying process. A linear relationship was obtained between CD and TPC with a good correlation of coefficient (R(2)=0.9816). Results of the study clearly indicated that transmission FTIR-PLS method could be used for quick and precise evaluation of oxidative changes during the frying process without using any organic solvent.

Sorption of Target Anions by Ligand Exchange

ABSTRACT: The sorption of anionic ligands such as I 0 ,Br 0 , and SCN 0 onto diamino-ethyl–sporopollenin (DAE–sporopollenin) was investigated in both column and batchexperiments at room temperature. The isotherm binding constants suggest that theresin is most efficient at the binding of I 0 compared with Br 0 or SCN 0 . The generalligand sorption affinity series observed was I 0 œBr 0 œSCN 0 . This ligand sorptioncould be described by considering the hydration of ions in the exchanger. The sorptionbehavior of the ligand exchanger and the possibilities of selectively removing and recov-ering ligands are discussed on the basis of their chemical and complexing properties. q 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 771–774, 1998 Key words: ligand exchange; sorption; anionic ligands; chelating polymers INTRODUCTION ficiently, are highly desirable for industrial appli-cations. 8–10 In particular, the sorption of contami-The ligand-exchange technique, which displays a nating inorganic ions such as thiocyanates andhigh selectivity for organic molecules and ions in cyanide is a major removalproblem from the pointan aqueous solution, has found extensive labora- of view of environmental pollution. Ligand-ex-tory and industrial application for removing tar- changeresins differfromthose ofcation andanionget contaminants.

Chemical Characterization of Canola and Sunflower Oil Deodorizer Distillates

Abstract In the present work deodorizer distillates of canola and sunflower oil were studied for their chemical characterization. Tocopherols, sterols, hydrocarbons and fatty acid composition were determined by Gas chromatography Mass spectrometry (GC-MS). Results indicated that deodorizer distillates of canola oil (DDCLO) studied had higher saponification value in the range of 164.2-175.8 mg/g and all deodorizer distillates of sunfl ower oil (DDSFO) had high iodine value of 126.2-127.1 g/100 g. Peroxide value and free fatty acids were present in the range between 7.0-8.9 mEq/Kg and 35.7-54.4 g/100 g in DDSFO and DDCLO samples, respectively. Contents of oleic acid (49.3-51.1 g/100 g) and linolenic acid (6.2-7.5 g/100 g) were significantly greater in DDCLO samples. Conversely, DDSFO contained concentrated amount of linoleic acid (52.8-53.3 g/100 g). Tocopherols and hydrocarbons were significantly higher in all DDSFO samples while, sterols were dominant in DDCLO samples. GC-MS provided excellent results for simultaneous determination of tocopherols, sterols, hydrocarbons and fatty acid composition of deodorizer distillates of canola and sunflower oil

DETERMINATION OF DEFENSIN HNP-1 IN HUMAN SALIVA OF PATIENTS WITH ORAL MUCOSAL DISEASES

Saliva is a biological fluid that is easily obtainable and that can give useful information both in systemic and oral diseases. In this study, a chromatographic method was applied to determine the amount of defensin HNP-1 in human saliva of patients with oral mucosal diseases before and after treatments and compared with controls. Defensin human neutrophil peptide-1 (HNP-1) was identified and confirmed. The concentration of HNP-1 in saliva was determined by comparing the area of eluted HNP-1 with that of HNP-1 standard. Linear calibration range of defensin HNP-1 was 0.10 to 0.90 μg/10 μL with R2 values of 0.996. The concentrations of HNP-1 in the saliva of patients with oral lichen planus, Behçets disease, and recurrent apthous stomatitis were 33.6 ± 10.6, 15.5 ± 7.6, and 36.3 ± 9.5 μg mL−1 (mean ± S.D.), respectively. The salivary defensin-1 concentration was significantly higher in patients with oral mucosal diseases than in healthy volunteers; furthermore, in patients with oral mucosal diseases, the concentration was significantly higher before treatment than after treatment.

A green approach for the production of biodiesel from fatty acids of corn deodorizer distillate

A novel alginic acid derived tin catalyst, tin alginate (Sn–Alg), was successfully synthesized, characterized and applied for methyl esterification. Initially, the amount of catalyst, methanol to fatty acid ratio and reaction time were optimized using an oleic acid standard for esterification. The optimal reaction conditions were found to be 4% catalyst, 1 : 12 oleic acid to methanol mole ratio and 2 h reaction time with 98.7% fatty acid methyl ester recovery. The capability of Sn–Alg beads to esterify the fatty acids of corn deodorizer distillate was evaluated. High recovery (97.6%) of esters was obtained after 8 cycles using reprocessed catalyst under the optimized parameters. The results of the present study indicated that based on the environmental pollution, reusability, avoiding the use of potassium or sodium hydroxides or sulphuric or phosphoric acids, and ease of catalyst separation, the solid Sn–Alg catalyst has a great potential for biodiesel production from highly free fatty acid deodorizer distillates.