Use of domestic minerals for vegetable oil bleaching

Thesis (Master)--Izmir Institute of Technology, Food Engineering, Izmir, 2004Includes bibliographical references (leaves: 58)Text in English; Abstract: Turkish and Englishxiii, 68 leavesIn this thesis, acid activation and characterization studies were conducted for different clay samples and bleaching capacity of the selected acid activated clay samples for sunflower oil were determined. The samples selected for this study were naturally occuring clays from Ankara and Eskiehir regions. The acid activated zeolite was also used for the purpose to compare its bleaching performance with commercial bleaching clay, Tonsil and the acid activated clays.The clay minerals were activated with hydrochloric acid (HCl) at three acid concentrations (1 N, 3 N, 5 N), activation times (1h, 2h, 3h) and different dry clay/acid ratios. The clay samples from the Ankara and Eskiehir regions were defined as montmorillonite according to X- ray diffraction (XRD). XRD results proved that acid activation caused structural changes in the treated montmorillonites, montmorillonite peaks gradually disappearing and yielding to an amorphous montmorillonite structure.The TGA results showed a significant weight loss between 30 C - 200 C ( 15%) for the Ankara clay and between 20 - 200 (12%) for the Eskiehir clay. This was most probably due to the removal of free and hydrogen-bonded water molecules. Maximum surface area was obtained for the acid activated Ankara clay treated with 1 N HCl for 3 hours. It was determined to be 849.1 m2/g. Also, maximum surface area was 269.7 m2/g for the acid activated Eskiehir clay treated with 5 N HCl for 1hour. Then the surface area of the acid activated clays decreased sharply with the acid activation. The chemical compositions of the solutions and clays after acid activation were determined using ICP and EDX analysis, respectively. According to the results, the dissolution amount of CaO, Na2O, MgO, K2O, Fe2O3 and Al2O3 increased along with increasing acid concentration and treatment time. The SiO2 content and the Si02/Al2O3 ratio increased as a result of dissolving of aluminium ions. This ratio increased from 6.0 to 7.5 for the acid activated Eskiehir clay and from 2.7 to 3.9 for acid activated Ankara clay.Acid activated clays were tested for the assessment of their bleaching efficiency for sunflower oil in the laboratory. Bleaching tests were carried out with earths prepared at different acid activation conditions such as acid concentration and activation times. The absorbance value was measured at 455 nm and found to be 0.429 for the neutralized sunflower oil. Peroxide value and free-fatty acid content of the neutralized oil were found to be 16.8 meq/kg and 0.07 %, respectively. The oil bleached with the acid activated Ankara clay had a peroxide value of 46.2 meq/kg first, which decreased to 22.4 meq/kg and the free-fatty acid content was observed to be around 0.08 %. For acid activated Eskiehir clay, peroxide value of the bleached oil initially increased up to 31.2 meq/kg, then decreased under the peroxide value of neutralized oil (16.8 meq/kg) and free-fatty acid content of bleached oil approximately was around 0.09 %.The bleaching parameters which were used for testing were 1 % earth concentration and 30 minutes contact time at 100°C bleaching temperature. At these selected parameters, acid activated Eskiehir clay (5 N 1h HCl treatment), Ankara clay (1 N 3h HCl treatment) and zeolite (2 N 6h HNO3 treatment) were compared with the commercial bleaching clay, Tonsil. The smallest value of absorbance and bleaching efficiency were found to be 0.084 and 80 %, respectively with the Eskiehir clay and these values were determined to be 0.083 and 81 % with the Tonsil under the same conditions. The absorbance value and bleaching efficiency of the bleached oil with acid activated Ankara clay were determined to be 0.114 and 73 %, respectively using the selected bleaching parameters. Bleaching performance of Ankara clay was found to be lower when compared with the result of Eskiehir clay.At the selected bleaching point, results of lovibond red and yellow color of bleached oil indicated that the Eskiehir clay and Tonsil were close to each other in bleaching efficiency (Red color: 0.8 and 1.1; yellow color: 20 and 20 for Tonsil and Eskiehir clay, respectively). Zeolite did not reach the required bleaching performance.The bleaching efficiency was 25 % with raw zeolite and it hardly increased to 46 % with the acid activated zeolite. In addition, red and yellow color values were higher than the other clays (red color:2.6; yellow color: 30).As a result, Eskiehir clay gave a better bleaching performance compared to Ankara clay and Zeolite. Maximum bleaching efficiency was achieved after 30 minutes of contact time with 1 % earth concentration at 100 °C bleaching temperature following 5 N 1h HCl treatment for Eskiehir clay

Sorption of N2, Co2 and CH4 On the ultrasound enhanced cation exchanged x zeolites

Thesis (Doctoral)--Izmir Institute of Technology, Chemical Engineering, Izmir, 2011Includes bibliographical references (leaves: 133-140)Text in English; Abstract: Turkish and Englishxv, 169 leavesLi+, Ca2+ and Ce3+ ions exchange on NaX zeolite under ultrasonic irradiation and the N2, CO2 and CH4 sorption on the zeolites obtained by using Zero Length Coulumn (ZLC) technique were studied. The kinetic and equilibrium of ion exchange were applied in the concentration range of 3-9 fold equivalent excess at 50 oC and 70 oC. The results obtained from the ultrasonic method was compared with the traditional method. Maximum exchange percent was obtained under ultrasonic irradiation as 76, 72 and 66 for Li+, Ca2+ and Ce3+ ions exchange, respectively. The kinetics of the ion exchange of Li+, Ca2+, Ce3+ ions into NaX zeolite has been investigated with models; pseudo first order, pseudo second order reaction models, intraparticle and external diffusion models. At initial, ion exchange is very fast kinetically and completed within about 15 min. After that both mechanism: intraparticle and external resistance are dominant which are proved with Biot number. The experimental conditions in zero length column are adjusted to control the adsorption under diffusion. The adsorbents selected for adsorption in ZLC have the convenient average pore diameters for CO2, N2 and CH4 adsorption. The kinetic gas selectivities, S(CO2/CH4), S(CO2/N2), S(N2/CH4) at 30 oC, 60 oC and 90 oC are lower than 5 for all the adsorbents. The lowest selectivity is obtained for NaX zeolite. The CO2 selectivity over CH4 and N2 are higher than N2 selectivity over CH4 for all the adsorbents S(CO2/CH4), S(CO2/N2) S(N2/CH4). This can be explained with the high electrostatic interaction and the low kinetic diameter of CO2 than the other gases

Enhancement of cerium exchange with ultrasound

In this study the effect of ultrasound of the cerium exchange was studied. The results were compared to those obtained from traditional batch exchange method. Contact time, initial cation concentration (fold equivalent excess) and the types of the ultrasound were studied. Ultrasonic probe, which is the most effective method, enhanced the replacement of Na+ ion with Ce3+ ion in the extra-framework of zeolite up to 73 % by applying 5 consecutive ion exchanges. The cerium in the solution caused to be formed cerium oxides on the crystal surface occluding the pores. Thus the specific surface area of cerium exchanged zeolite was decreased due to formation of cerium complexes on the surface and into the pores. © 2018, Turkish Chemical Society. All rights reserved.Izmir Institute of Technology (Project number: 2006IYTE31) and State Planning Organization of Turkey (DPT

Sociotropic personality traits positively correlate with the severity of social anxiety

Aim. To investigate sociotropic-autonomic personality characteristics and their clinical implications in social anxiety disorder (SAD).  Methods. The study included 68 consecutive patients who were either being followed up on an outpatient basis or presented for the first time to the psychiatric clinics of Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery or Trakya University School of Medicine between May 2012 and May 2013, and were diagnosed primarily with generalised SAD according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) diagnostic criteria. Beck Depression Inventory (BDI), Sociotropy-Autonomy Scale (SAS), Symptom Checklist-90-R (SCL-90-R), Liebowitz Social Anxiety Scale (LSAS) and a sociodemographic data collection form designed by the authors were used as primary assessment instruments.  Results. The mean age (standard deviation (SD)) of the sample group was 23.73 (8.85) years; 37 (54.4%) were female and 31 (45.6%) were male. LSAS mean (SD) total fear score was 63.51 (13.74), mean total avoidance score was 61.24 (14.26), BDI mean score was 16.99 (9.58), SAS mean sociotropy score was 71.06 (16.79), and mean autonomy score was 63.22 (16.04). A statistically significant positive correlation was found between SAS sociotropy scores and LSAS fear and avoidance total scores, BDI scores and all subscales of SCL-90-R (p<0.01). There were no statistically significant correlations between SAS autonomy scores and LSAS fear and avoidance total scores, BDI scores and all subscales of SCL-90-R (p>0.05).  Conclusion. Sociotropic personality characteristics in patients with SAD have been found to positively correlate with depression and social anxiety levels. Addressing this finding during treatment sessions and helping the patient increase flexibility in appraisal of social life events may have a positive impact on treatment outcome

Association of Serum Adropin Levels with Nutritional Status and Lipid Profile in Patients with Kidney Failure with Replacement Therapy

Objective. This study aimed to determine serum adropin levels and to examine the relationship of serum adropin levels with nutritional status and lipid profile in patients with kidney failure with replacement therapy (KFRT). Methods. The study consisted of 88 subjects, including 30 patients treated with hemodialysis (HD), 29 patients treated with peritoneal dialysis (PD), and 29 patients who had undergone kidney transplantation (TX). The study included assessing anthropometric measurements, handgrip strength, bioelectrical impedance analysis, malnutrition-inflammation score, dietary intake, resting energy expenditure, and biochemical parameters. The patients’ food consumption was recorded for three days. The malnutrition-inflammation score (MIS) was calculated to assess the patients’ nutritional status. Blood samples were collected for serum adropin and other biochemical parameters. Results. Adropin levels were significantly higher in the TX group when compared to the HD group. Patients with low adropin levels had higher MIS, serum ferritin, and lower low-density lipoprotein-cholesterol (LDL-C) and total cholesterol (total-C) levels. Serum adropin levels were negatively correlated with the MIS and positively correlated with total-C, LDL-C, and HDL-C levels. Multiple linear regression analyses showed that the MIS (β=-0.25 p=0.038) and LDL-C level (β=0.29, p=0.007) were associated with serum adropin. Conclusions. Adropin may be considered as a new marker of nutritional status and possibly plays a role in the pathophysiological mechanisms and complications of patients with KFRT

Use of domestic minerals for vegetable oil bleaching

Thesis (Master)--Izmir Institute of Technology, Food Engineering, Izmir, 2004Includes bibliographical references (leaves: 58)Text in English; Abstract: Turkish and Englishxiii, 68 leavesIn this thesis, acid activation and characterization studies were conducted for different clay samples and bleaching capacity of the selected acid activated clay samples for sunflower oil were determined. The samples selected for this study were naturally occuring clays from Ankara and Eskiehir regions. The acid activated zeolite was also used for the purpose to compare its bleaching performance with commercial bleaching clay, Tonsil and the acid activated clays.The clay minerals were activated with hydrochloric acid (HCl) at three acid concentrations (1 N, 3 N, 5 N), activation times (1h, 2h, 3h) and different dry clay/acid ratios. The clay samples from the Ankara and Eskiehir regions were defined as montmorillonite according to X- ray diffraction (XRD). XRD results proved that acid activation caused structural changes in the treated montmorillonites, montmorillonite peaks gradually disappearing and yielding to an amorphous montmorillonite structure.The TGA results showed a significant weight loss between 30 C - 200 C ( 15%) for the Ankara clay and between 20 - 200 (12%) for the Eskiehir clay. This was most probably due to the removal of free and hydrogen-bonded water molecules. Maximum surface area was obtained for the acid activated Ankara clay treated with 1 N HCl for 3 hours. It was determined to be 849.1 m2/g. Also, maximum surface area was 269.7 m2/g for the acid activated Eskiehir clay treated with 5 N HCl for 1hour. Then the surface area of the acid activated clays decreased sharply with the acid activation. The chemical compositions of the solutions and clays after acid activation were determined using ICP and EDX analysis, respectively. According to the results, the dissolution amount of CaO, Na2O, MgO, K2O, Fe2O3 and Al2O3 increased along with increasing acid concentration and treatment time. The SiO2 content and the Si02/Al2O3 ratio increased as a result of dissolving of aluminium ions. This ratio increased from 6.0 to 7.5 for the acid activated Eskiehir clay and from 2.7 to 3.9 for acid activated Ankara clay.Acid activated clays were tested for the assessment of their bleaching efficiency for sunflower oil in the laboratory. Bleaching tests were carried out with earths prepared at different acid activation conditions such as acid concentration and activation times. The absorbance value was measured at 455 nm and found to be 0.429 for the neutralized sunflower oil. Peroxide value and free-fatty acid content of the neutralized oil were found to be 16.8 meq/kg and 0.07 %, respectively. The oil bleached with the acid activated Ankara clay had a peroxide value of 46.2 meq/kg first, which decreased to 22.4 meq/kg and the free-fatty acid content was observed to be around 0.08 %. For acid activated Eskiehir clay, peroxide value of the bleached oil initially increased up to 31.2 meq/kg, then decreased under the peroxide value of neutralized oil (16.8 meq/kg) and free-fatty acid content of bleached oil approximately was around 0.09 %.The bleaching parameters which were used for testing were 1 % earth concentration and 30 minutes contact time at 100°C bleaching temperature. At these selected parameters, acid activated Eskiehir clay (5 N 1h HCl treatment), Ankara clay (1 N 3h HCl treatment) and zeolite (2 N 6h HNO3 treatment) were compared with the commercial bleaching clay, Tonsil. The smallest value of absorbance and bleaching efficiency were found to be 0.084 and 80 %, respectively with the Eskiehir clay and these values were determined to be 0.083 and 81 % with the Tonsil under the same conditions. The absorbance value and bleaching efficiency of the bleached oil with acid activated Ankara clay were determined to be 0.114 and 73 %, respectively using the selected bleaching parameters. Bleaching performance of Ankara clay was found to be lower when compared with the result of Eskiehir clay.At the selected bleaching point, results of lovibond red and yellow color of bleached oil indicated that the Eskiehir clay and Tonsil were close to each other in bleaching efficiency (Red color: 0.8 and 1.1; yellow color: 20 and 20 for Tonsil and Eskiehir clay, respectively). Zeolite did not reach the required bleaching performance.The bleaching efficiency was 25 % with raw zeolite and it hardly increased to 46 % with the acid activated zeolite. In addition, red and yellow color values were higher than the other clays (red color:2.6; yellow color: 30).As a result, Eskiehir clay gave a better bleaching performance compared to Ankara clay and Zeolite. Maximum bleaching efficiency was achieved after 30 minutes of contact time with 1 % earth concentration at 100 °C bleaching temperature following 5 N 1h HCl treatment for Eskiehir clay

Sorption of N2, Co2 and CH4 On the ultrasound enhanced cation exchanged x zeolites

Thesis (Doctoral)--Izmir Institute of Technology, Chemical Engineering, Izmir, 2011Includes bibliographical references (leaves: 133-140)Text in English; Abstract: Turkish and Englishxv, 169 leavesLi+, Ca2+ and Ce3+ ions exchange on NaX zeolite under ultrasonic irradiation and the N2, CO2 and CH4 sorption on the zeolites obtained by using Zero Length Coulumn (ZLC) technique were studied. The kinetic and equilibrium of ion exchange were applied in the concentration range of 3-9 fold equivalent excess at 50 oC and 70 oC. The results obtained from the ultrasonic method was compared with the traditional method. Maximum exchange percent was obtained under ultrasonic irradiation as 76, 72 and 66 for Li+, Ca2+ and Ce3+ ions exchange, respectively. The kinetics of the ion exchange of Li+, Ca2+, Ce3+ ions into NaX zeolite has been investigated with models; pseudo first order, pseudo second order reaction models, intraparticle and external diffusion models. At initial, ion exchange is very fast kinetically and completed within about 15 min. After that both mechanism: intraparticle and external resistance are dominant which are proved with Biot number. The experimental conditions in zero length column are adjusted to control the adsorption under diffusion. The adsorbents selected for adsorption in ZLC have the convenient average pore diameters for CO2, N2 and CH4 adsorption. The kinetic gas selectivities, S(CO2/CH4), S(CO2/N2), S(N2/CH4) at 30 oC, 60 oC and 90 oC are lower than 5 for all the adsorbents. The lowest selectivity is obtained for NaX zeolite. The CO2 selectivity over CH4 and N2 are higher than N2 selectivity over CH4 for all the adsorbents S(CO2/CH4), S(CO2/N2) S(N2/CH4). This can be explained with the high electrostatic interaction and the low kinetic diameter of CO2 than the other gases