Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0366-5
Nuša Hojnik, M. Kristl, A. Golobič, Z. Jagličić, M. Drofenik
AbstractThis article reports the synthesis of novel, rare-earth coordination complexes with nicotinic acid. Three compounds with the general formula Ln2[(C5H4NCOO)6(H2O)4] (Ln = Yb, 1; Ln = Gd, 2; Ln = Nd, 3) were prepared from relatively cheap and readily available reactants. Their compositions and structure were characterized by IR spectroscopy and single-crystal X-ray diffraction. The magnetic and thermogravimetric properties were also studied. The complexes consist of centrosymetric, dimeric molecules having all six nicotinato ligands coordinated with the central atom in the bidentate mode. The coordination environment of the Ln3+ for all three compounds is 8. Here we describe the crystal structure of Yb and Gd complexes with nicotinic acid.
{"title":"The synthesis, structure and physical properties of lanthanide(III) complexes with nicotinic acid","authors":"Nuša Hojnik, M. Kristl, A. Golobič, Z. Jagličić, M. Drofenik","doi":"10.2478/s11532-013-0366-5","DOIUrl":"https://doi.org/10.2478/s11532-013-0366-5","url":null,"abstract":"AbstractThis article reports the synthesis of novel, rare-earth coordination complexes with nicotinic acid. Three compounds with the general formula Ln2[(C5H4NCOO)6(H2O)4] (Ln = Yb, 1; Ln = Gd, 2; Ln = Nd, 3) were prepared from relatively cheap and readily available reactants. Their compositions and structure were characterized by IR spectroscopy and single-crystal X-ray diffraction. The magnetic and thermogravimetric properties were also studied. The complexes consist of centrosymetric, dimeric molecules having all six nicotinato ligands coordinated with the central atom in the bidentate mode. The coordination environment of the Ln3+ for all three compounds is 8. Here we describe the crystal structure of Yb and Gd complexes with nicotinic acid.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"30 1","pages":"220-226"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86846860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0371-8
N. Velinov, K. Koleva, T. Tsoncheva, D. Paneva, E. Manova, K. Tenchev, B. Kunev, I. Genova, I. Mitov
AbstractCopper-cobalt ferrites with composition Cu1−xCoxFe2O4, where x= 0.2 and 0.8 were prepared by thermal treatment of co-precipitated precursor. The obtained materials were characterized by TG-DSC, XRD, Transmission and Conversion Electron Mössbauer spectroscopy and temperature programmed reduction with hydrogen. The catalytic properties of ferrites were tested in methanol decomposition to CO and hydrogen.
{"title":"Copper-cobalt ferrites as catalysts for methanol decomposition","authors":"N. Velinov, K. Koleva, T. Tsoncheva, D. Paneva, E. Manova, K. Tenchev, B. Kunev, I. Genova, I. Mitov","doi":"10.2478/s11532-013-0371-8","DOIUrl":"https://doi.org/10.2478/s11532-013-0371-8","url":null,"abstract":"AbstractCopper-cobalt ferrites with composition Cu1−xCoxFe2O4, where x= 0.2 and 0.8 were prepared by thermal treatment of co-precipitated precursor. The obtained materials were characterized by TG-DSC, XRD, Transmission and Conversion Electron Mössbauer spectroscopy and temperature programmed reduction with hydrogen. The catalytic properties of ferrites were tested in methanol decomposition to CO and hydrogen.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"45 1","pages":"250-259"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78619583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0361-x
Dawid Lewandowski, A. Olejnik, G. Schroeder
AbstractFunctionalized mesoporous MCM-41 silica was subjected to adsorption and release studies of encapsulated guest molecules of three chosen dyes. These mesoporous systems were composed of three different capping reagents introduced by grafting method on the silica surface to control the release of dye molecules at two different pH values. The amounts of dyes adsorbed on the silica surface were measured using ultraviolet-visible (UV-VIS) spectrophotometry. The efficiency of grafting was calculated on the basis of differential thermal analysis (TG) results and elemental analysis. The release profiles were determined for all obtained systems using USP Dissolution Apparatus 2. Adsorption of the two azo dyes used was the most efficient after the positively charged functionalization and lower after functionalization with neutral and negatively charged capping reagents, while the phthalocyanine dye adsorption was almost functionalization-independent. Grafting efficiency was the highest for neutral capping reagent and much lower for electrically charged molecules of other reagents. Release studies showed clearly that desorption was pH-dependent for azo dyes and pH independent for Alcian Blue. The adsorption and release seem to be connected with the electrical charge of all constituents of these systems. Results obtained can be used for further analysis of different electrically charged molecules.
{"title":"Adsorption studies and release of selected dyes from functionalized mesoporous MCM-41 silica","authors":"Dawid Lewandowski, A. Olejnik, G. Schroeder","doi":"10.2478/s11532-013-0361-x","DOIUrl":"https://doi.org/10.2478/s11532-013-0361-x","url":null,"abstract":"AbstractFunctionalized mesoporous MCM-41 silica was subjected to adsorption and release studies of encapsulated guest molecules of three chosen dyes. These mesoporous systems were composed of three different capping reagents introduced by grafting method on the silica surface to control the release of dye molecules at two different pH values. The amounts of dyes adsorbed on the silica surface were measured using ultraviolet-visible (UV-VIS) spectrophotometry. The efficiency of grafting was calculated on the basis of differential thermal analysis (TG) results and elemental analysis. The release profiles were determined for all obtained systems using USP Dissolution Apparatus 2. Adsorption of the two azo dyes used was the most efficient after the positively charged functionalization and lower after functionalization with neutral and negatively charged capping reagents, while the phthalocyanine dye adsorption was almost functionalization-independent. Grafting efficiency was the highest for neutral capping reagent and much lower for electrically charged molecules of other reagents. Release studies showed clearly that desorption was pH-dependent for azo dyes and pH independent for Alcian Blue. The adsorption and release seem to be connected with the electrical charge of all constituents of these systems. Results obtained can be used for further analysis of different electrically charged molecules.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"392 1","pages":"233-241"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76911567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0363-8
I. Pohrelyuk, O. Tkachuk, R. Proskurnyak
AbstractThe corrosion properties of Ti-6Al-4V alloy with oxidized thermodiffusion nitride coatings were investigated in isotonic 0.9% solution of NaCl at temperature of 40°C. It was shown that modification of nitride coatings by oxygen leads to a deterioration of the protective properties of nitrided surface of Ti-6Al-4V alloy. The protective properties of the alloy with nitride coatings modified by oxygen are determined by the composition of formed surface oxynitride film.
{"title":"Effect of oxidation of nitride coatings on corrosion properties of Ti-6Al-4V alloy in 0.9% NaCl at 40°C","authors":"I. Pohrelyuk, O. Tkachuk, R. Proskurnyak","doi":"10.2478/s11532-013-0363-8","DOIUrl":"https://doi.org/10.2478/s11532-013-0363-8","url":null,"abstract":"AbstractThe corrosion properties of Ti-6Al-4V alloy with oxidized thermodiffusion nitride coatings were investigated in isotonic 0.9% solution of NaCl at temperature of 40°C. It was shown that modification of nitride coatings by oxygen leads to a deterioration of the protective properties of nitrided surface of Ti-6Al-4V alloy. The protective properties of the alloy with nitride coatings modified by oxygen are determined by the composition of formed surface oxynitride film.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"57 1","pages":"260-265"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74378953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0369-2
T. Voronchak, Irena Nykulyshyn, Z. Pikh, Anna Rypka, Z. Gnativ
AbstractCooligomerization of liquid products of the C9 fraction of diesel fuel pyrolysis to produce cooligomers of wide application is suggested to be carried out with silica-alumina catalysts, among which the activated bentonite clay seems to be optimal. Cooligomerization of the mixture simulating the C9 fraction composition was studied to compare the suggested heterogeneous catalytic method with other methods of cooligomers production. Different methods have been compared in terms of yield of cooligomers and their properties, namely molecular weight and its distribution, density, unsaturation and colour. The ratio of monomer units in cooligomer has been determined and the monomers conversion degrees have been calculated for different cooligomerization methods. Reasons of structure and composition differences of cooligomers obtained by different methods are suggested.
{"title":"Cooligomerization of dominant monomers of C9 fraction of liquid pyrolysis products: comparison of heterogeneous catalytic approach with common methods","authors":"T. Voronchak, Irena Nykulyshyn, Z. Pikh, Anna Rypka, Z. Gnativ","doi":"10.2478/s11532-013-0369-2","DOIUrl":"https://doi.org/10.2478/s11532-013-0369-2","url":null,"abstract":"AbstractCooligomerization of liquid products of the C9 fraction of diesel fuel pyrolysis to produce cooligomers of wide application is suggested to be carried out with silica-alumina catalysts, among which the activated bentonite clay seems to be optimal. Cooligomerization of the mixture simulating the C9 fraction composition was studied to compare the suggested heterogeneous catalytic method with other methods of cooligomers production. Different methods have been compared in terms of yield of cooligomers and their properties, namely molecular weight and its distribution, density, unsaturation and colour. The ratio of monomer units in cooligomer has been determined and the monomers conversion degrees have been calculated for different cooligomerization methods. Reasons of structure and composition differences of cooligomers obtained by different methods are suggested.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"6 1","pages":"266-280"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79204086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0375-4
S. Khalameida, V. Sydorchuk, R. Leboda, J. Skubiszewska-Zięba, V. Zazhigalov
AbstractModified compositions in the system V2O5/(NH4)2Mo2O7 have been prepared by means of mechanochemical, hydrothermal, microwave and ultrasonic treatments in aqueous medium. Chemical and phase transformations occurring on the stages of modification and following calcinations have been studied with the help of XRD, DTA-TG, FTIR and UV-Vis spectroscopy, nitrogen adsorption, and SEM. It has been established that precursors of catalytically active phases possessing meso-macroporous structure have been formed during modification. The comparison of the properties of compositions prepared via different methods has been carried out. Particularly, precursors modified via various procedures possess different morphology.
{"title":"Physical-chemical transformations in the system V2O5/(NH4)2Mo2O7 under hydrothermal conditions","authors":"S. Khalameida, V. Sydorchuk, R. Leboda, J. Skubiszewska-Zięba, V. Zazhigalov","doi":"10.2478/s11532-013-0375-4","DOIUrl":"https://doi.org/10.2478/s11532-013-0375-4","url":null,"abstract":"AbstractModified compositions in the system V2O5/(NH4)2Mo2O7 have been prepared by means of mechanochemical, hydrothermal, microwave and ultrasonic treatments in aqueous medium. Chemical and phase transformations occurring on the stages of modification and following calcinations have been studied with the help of XRD, DTA-TG, FTIR and UV-Vis spectroscopy, nitrogen adsorption, and SEM. It has been established that precursors of catalytically active phases possessing meso-macroporous structure have been formed during modification. The comparison of the properties of compositions prepared via different methods has been carried out. Particularly, precursors modified via various procedures possess different morphology.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"51 1","pages":"140-152"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79539092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0367-4
K. Nieszporek, Tomasz Banach, P. Podkościelny
AbstractThe Non-Random Two-Liquid activity coefficient model is applied to describe the kinetics of pure gas adsorption on energetically heterogeneous solid surfaces. The surface energetic heterogeneity has been represented by the Gaussian-like function of the adsorption energy distribution. Two different kinetic isotherms have been presented. One of them, determined by using the statistical rate theory, has been critically discussed. The applicability of the presented approach has been demonstrated by a quantitative analysis of two sets of experimental data previously reported in the literature.
{"title":"Application of NRTL activity coefficient model to describe the kinetics of gas adsorption","authors":"K. Nieszporek, Tomasz Banach, P. Podkościelny","doi":"10.2478/s11532-013-0367-4","DOIUrl":"https://doi.org/10.2478/s11532-013-0367-4","url":null,"abstract":"AbstractThe Non-Random Two-Liquid activity coefficient model is applied to describe the kinetics of pure gas adsorption on energetically heterogeneous solid surfaces. The surface energetic heterogeneity has been represented by the Gaussian-like function of the adsorption energy distribution. Two different kinetic isotherms have been presented. One of them, determined by using the statistical rate theory, has been critically discussed. The applicability of the presented approach has been demonstrated by a quantitative analysis of two sets of experimental data previously reported in the literature.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"24 1","pages":"185-193"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88020345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0372-7
Ahmad Seif, Lila Torkashavand, F. Mohammadi
AbstractWe have investigated oxygen decorating in the (10, 0) aluminum nitride nanotube (AlNNT) by density functional theory. Band gaps, total (TDOS) and partial (PDOS) densities of state and chemical-shielding isotropic (CSI) and chemical-shielding anisotropic (CSA) have been calculated or determined in three models of the investigated (10, 0) AlNNT: pristine (model.0), O-decorating at the one ring in the middle of AlNNT (Model.1) and O-decorating at the nitrogen mouth of AlNNT (Model.2). The results indicated that the dipole moment does not detect the significant effects of dopant whereas TDOS, PDOS and band gap energies detect notable effects. The CSI and CSA values for the Al and N atoms-contributed to the Al-O bonds or those atoms close to the decorated region, in both models of O-decorated AlNNTs are changed.
{"title":"Oxygen decorating at the one ring and at the N-mouth of (10, 0) aluminum nitride nanotube: A DFT investigation","authors":"Ahmad Seif, Lila Torkashavand, F. Mohammadi","doi":"10.2478/s11532-013-0372-7","DOIUrl":"https://doi.org/10.2478/s11532-013-0372-7","url":null,"abstract":"AbstractWe have investigated oxygen decorating in the (10, 0) aluminum nitride nanotube (AlNNT) by density functional theory. Band gaps, total (TDOS) and partial (PDOS) densities of state and chemical-shielding isotropic (CSI) and chemical-shielding anisotropic (CSA) have been calculated or determined in three models of the investigated (10, 0) AlNNT: pristine (model.0), O-decorating at the one ring in the middle of AlNNT (Model.1) and O-decorating at the nitrogen mouth of AlNNT (Model.2). The results indicated that the dipole moment does not detect the significant effects of dopant whereas TDOS, PDOS and band gap energies detect notable effects. The CSI and CSA values for the Al and N atoms-contributed to the Al-O bonds or those atoms close to the decorated region, in both models of O-decorated AlNNTs are changed.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"132 1","pages":"131-139"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89235412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0364-7
Y. Tyvanchuk, V. Svitlyk, Mykola Pustovoychenko, Y. Kalychak
AbstractPolycrystalline Sm4Ni11In20 was obtained by arc-melting of metal ingots. A subsequent high temperature treatment was used for single crystal growth. The Sm4Ni11In20 crystal structure (U4Ni11Ga20 type; C2/m, a = 22.5457(3) Å, b = 4.34929(5) Å, c = 16.5479(2) Å, β = 124.592(2)°, R1 = 0.0358, wR2 = 0.0934) was determined by single crystal synchrotron radiation X-ray diffraction from 2014 independent reflections with I > 2σ(I). Sm4Ni11In20 extends the R4Ni11In20 (R = Y, Gd, Tb, Dy, Ho) series of phases. The R4Ni11In20 and RNi3In6 (LaNi3In6 type; R = La, Ce, Pr, Nd, Eu) series have similar compositions. Their structures share similar fragments; in particular the rare earth atom coordination polyhedra are pentagonal prisms with additional atoms.
摘要采用电弧熔炼法制备了Sm4Ni11In20多晶。随后的高温处理用于单晶生长。Sm4Ni11In20晶体结构(U4Ni11Ga20型;单晶同步辐射x射线衍射测定了2014年I > 2σ(I)独立反射的C2/m, a = 22.5457(3) Å, b = 4.34929(5) Å, c = 16.5479(2) Å, β = 124.592(2)°,R1 = 0.0358, wR2 = 0.0934。Sm4Ni11In20扩展了R4Ni11In20 (R = Y, Gd, Tb, Dy, Ho)系列相。R4Ni11In20和RNi3In6 (LaNi3In6型;R = La, Ce, Pr, Nd, Eu)系列具有相似的成分。它们的结构有相似的片段;稀土原子配位多面体是带有附加原子的五角形多面体。
{"title":"The crystal structure of Sm4Ni11In20 and its relation to other indium-rich compounds","authors":"Y. Tyvanchuk, V. Svitlyk, Mykola Pustovoychenko, Y. Kalychak","doi":"10.2478/s11532-013-0364-7","DOIUrl":"https://doi.org/10.2478/s11532-013-0364-7","url":null,"abstract":"AbstractPolycrystalline Sm4Ni11In20 was obtained by arc-melting of metal ingots. A subsequent high temperature treatment was used for single crystal growth. The Sm4Ni11In20 crystal structure (U4Ni11Ga20 type; C2/m, a = 22.5457(3) Å, b = 4.34929(5) Å, c = 16.5479(2) Å, β = 124.592(2)°, R1 = 0.0358, wR2 = 0.0934) was determined by single crystal synchrotron radiation X-ray diffraction from 2014 independent reflections with I > 2σ(I). Sm4Ni11In20 extends the R4Ni11In20 (R = Y, Gd, Tb, Dy, Ho) series of phases. The R4Ni11In20 and RNi3In6 (LaNi3In6 type; R = La, Ce, Pr, Nd, Eu) series have similar compositions. Their structures share similar fragments; in particular the rare earth atom coordination polyhedra are pentagonal prisms with additional atoms.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"71 1","pages":"227-232"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75439973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-02-01DOI: 10.2478/s11532-013-0368-3
P. Mierczyński, P. Kaczorowski, A. Ura, W. Maniukiewicz, M. Zaborowski, R. Ciesielski, A. Kedziora, T. Maniecki
AbstractTernary CuO-ZrO2-Al2O3 catalysts promoted by palladium or gold were prepared and tested in CO hydrogenation reaction at 260°C under elevated pressure (4.8 MPa). The promotion effect of palladium or gold addition on the physicochemical and catalytical properties of CuO-ZrO2-Al2O3 catalysts in methanol synthesis (MS) was studied. The catalysts were characterized by BET, XRD, TPR-H2, TPD-NH3 methods. The BET results showed that the ternary system CuO-ZrO2-Al2O3 had the largest specific surface area, cumulative pore volume and average pore size in comparison with the promoted catalysts. The yield of methanol can be given through the following sequence: 5%Pd/CuO-ZrO2-Al2O3 > CuO-ZrO2-Al2O3 > 2%Au/CuO-ZrO2-Al2O3. We also found that the presence of gold or palladium on catalyst surface has strong influence on the reaction selectivity. The high selectivity of gold doped ternary catalyst is explained by the gold-oxide interface sites created on the catalyst surface and the acidity of those systems. The higher selectivity to methanol in the case of the palladium catalyst is explained by the spillover effect between Pd and CuO.
{"title":"Promoted ternary CuO-ZrO2-Al2O3 catalysts for methanol synthesis","authors":"P. Mierczyński, P. Kaczorowski, A. Ura, W. Maniukiewicz, M. Zaborowski, R. Ciesielski, A. Kedziora, T. Maniecki","doi":"10.2478/s11532-013-0368-3","DOIUrl":"https://doi.org/10.2478/s11532-013-0368-3","url":null,"abstract":"AbstractTernary CuO-ZrO2-Al2O3 catalysts promoted by palladium or gold were prepared and tested in CO hydrogenation reaction at 260°C under elevated pressure (4.8 MPa). The promotion effect of palladium or gold addition on the physicochemical and catalytical properties of CuO-ZrO2-Al2O3 catalysts in methanol synthesis (MS) was studied. The catalysts were characterized by BET, XRD, TPR-H2, TPD-NH3 methods. The BET results showed that the ternary system CuO-ZrO2-Al2O3 had the largest specific surface area, cumulative pore volume and average pore size in comparison with the promoted catalysts. The yield of methanol can be given through the following sequence: 5%Pd/CuO-ZrO2-Al2O3 > CuO-ZrO2-Al2O3 > 2%Au/CuO-ZrO2-Al2O3. We also found that the presence of gold or palladium on catalyst surface has strong influence on the reaction selectivity. The high selectivity of gold doped ternary catalyst is explained by the gold-oxide interface sites created on the catalyst surface and the acidity of those systems. The higher selectivity to methanol in the case of the palladium catalyst is explained by the spillover effect between Pd and CuO.\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"4 1","pages":"206-212"},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78787905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}