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AZERBAIJAN CHEMICAL JOURNAL № 1 2019
UDC 542.943, 547.313.3 OXIDATIVE CONVERSION OF PROPYLENE TO ACROLEIN ON METAL ZEOLITE
CATALYSTS
A.M.Aliyev, U.M.Najaf-Guliyev, T.I.Huseynova, V.M.Yariyev, E.M.Kazimova*
M.Nagiyev Institute of Catalysis and Inorganic Chemistry, NAS of Azerbaijan * Azerbaijan University of Architecture and Construction
Received 28.11.2018
Catalytic activity of modified zeolites in the reactions of oxidative conversion of propylene to acrolein was studied. It was established that Ni-clinoptilolite (1% Ni2+) exhibits high activity in the studied reaction. The influence of the reaction temperature and volume rate on product yield on the active catalyst was investigated.
Keywords: oxidative conversion, acrolein, Ni-clinoptilolite, mordenite, activity, NaY, NaX, NaA.
https://doi.org/10.32737/0005-2531-2019-1-28-31
Introduction
Acrolein is an initial raw material for obtaining a wide range of valuable products. The main direction of processing acrolein is the production of acrylic acid used to produce effective sorbents, acrylic emulsions in lacquer dye industry, drilling reagents, polyacrylonitrile fiber and acrylate rubbers, construction mixtures and glues. Acrolein is used as an intermediate product in production of synthetic glycerin, plastics and other important products. For example, me-thionine or y-methylthiol-a-aminobutyric acid which is an effective fodder addition for poultry is obtained from acrolein.
For the first time acrolein was produced by condensation of acetaldehyde with formaldehyde. Presently the only and almost important way of its synthesis is oxidation of propylene which has clear advantages over previous method [1].
Preparation of catalysts directing the oxidation towards primary formation of acrolein was of great importance for a selective performance of the process. The first of them was cuprous oxide on carriers (0.1-1.5% Cu2O on pumice, a carborundum SiC or Al2O3) or even copper tubes of the reactor. Disadvantage of the process is that reaction goes at a high temperature and degree of conversion of propylene to acrolein is very low.
Contacts were developed later from bismuth molybdate (Bi2O3 MoO3) and bismuth phosphormolybdate (Bi2O3MoO3P2O5) containing promotors. On these catalysts rather high
selectivity is achieved at a short time of contact and moderate temperature. Disadvantage of the process is that reaction proceeds at a high temperature and yield of acrolein is very low [2].
From literature data studied by us it was found out that the reaction of oxidative conversion of propylene to acrolein is mainly performed with the presence of catalysts modified by various metals and containing oxides Bi-Mo. However, oxidative conversion of propyl-ene to acrolein on metalzeolite catalysts belongs to insufficiently known heterogeneous-catalytic reactions which proceeds with oxygen.
The present work provides the research results of oxidative conversion of propylene to detect the conditions of selective formation to acrolein in the presence of modified zeolite catalysts. The role of many modifiers used for the preparation of zeolite-containing catalysts has not been clarified. Great problem is the stability of the work of zeolite-containing catalysts which depends on many factors, including resistance to coke formation and regenerability, as well as fixation of modifying additions on zeolite support.
Experimental part
The reaction was performed on the laboratory-scale flowing unit with quartz reactor under stationary layer of a catalyst at atmospheric pressure in the temperature range of 320-3800C, volume rate of 700-1400 h-1 and molar ratio C3H6:O2=1.8:(1-1.8).
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In the work we used synthetic zeolites NaY (SiO2/Al2O3=X=4.2), NaX (X=2.9), NaA (X=2.0) and natural zeolites - clinoptilolite (X=10) and mordenite (X=9.6) from the deposits of Azerbaijan modified by different cations of transition and nontransition elements (Ni, Zn, Cu, Co, Cr, Mn, Fe, Mg, Mn, Bi, Pd and so on).
Catalysts were synthesized using ionexchange method [3]. Before ion-exchang natural zeolites were processed by 0.5 N HCl. The amount of introduced elements into the composition of zeolite was determined by ion spectral analysis on "ICP-MS Agilent 7700" and was 0.1-2% from zeolite mass. In the work we used catalysts with the size of particles 0.25-0.63 mm, 99.2% propylene, 99.3% oxygen, 99.9% helium.
Analysis of raw materials and reaction products was performed on gas chromatograph connected directly with a reactionary unit. Separation of reaction products was conducted in a column of 3 m in length filled with paropac-PC under the conditions of linear programmed rise
Table 1. Oxidative conversion of propylene to acrolein i 1.8:1)_
of temperature of thermostat chromatograph from 50 to 2000C.
Reaction products were also analyzed on gas chromatograph "Agilent 7890" with mass detector "Agilent 5975" with column HP-5 MS of 30 m in length.
Results and discussion
At first catalytic activity of primary zeolites in oxidative conversion reaction of propyl-ene was studied. Table 1 shows the results of studies on zeolites which do not contain metal cations. The results of studies confirmed that Na-forms (NaY, NaX) of zeolites are not practically activated in this reaction. Unlike wide-pore narrow-pore zeolites characterized with less surface (8.0-20.0 m /g) and small sizes of pores (4.2-4.9A) facilitate conversion of propylene to acrolein.
As follows from Table 1 among cation forms of narrow-pore zeolites the highest yield of acrolein is observed on natural clinoptilolite.
different initial zeolites (7=380°C, V0=700 h-1, C3H6:O2=
Zeolite x, % 5, % Yield of reaction products, %
CO2 HCOH C3H4O HCOOH
NaY 24.7 - 21.5 3.2 - -
NaX 20.5 - 18.4 2.1 - -
NaA 11.49 12.18 2.1 7.9 1.4 0.09
Mordenite 13.11 14.49 2.8 8.3 1.9 0.11
Clinoptilolite 19.9 21.1 3.5 10.4 4.2 1.8
Note: x - conversion of propylene, 5 - selectivity of the process by acrolein
Table 2. Oxidative conversion of propylene to acrolein on modified natural clinoptilolite (7=3800C, V0=700 h-1, CsH6:O2=1.8:1)_
Number of experiment Composition of zeolite, mass.% x, % 5, % Yield of reaction products, %
CO2 HCOH C3H4O HCOOH
1 Zn (0.2%) 37.5 5.25 22.13 13.4 1.97 -
2 Cu (0.5%) 58.27 - 38.65 19.6 - -
3 Co (0.5%) 59.81 - 46.37 13.44 - -
4 Mg (1%) 63.03 68.47 8.86 10.31 43.16 0.66
5 Pd (1%) 60.37 - 53.37 7 - -
6 Ni (1%) 94.72 85.44 5.44 5.75 80.93 2.6
7 Ni (3%) 69.83 68.85 11.96 4.19 48.08 5.6
8 Ni (5%) 74.36 48.95 25.74 8.02 36.04 4.2
9 CuFe (0.5: 0.25) 56.03 18.03 29.8 15.7 10.1 0.4
10 CuPd (0.5: 0.25) 50.53 - 50.03 - - -
11 CoBi (0.5: 1) 53.83 26.56 24.09 15.07 14.3 0.37
12 ZnCoCr (02:0.5:0.25) 68.35 65 14.96 8.4 44.43 0.56
13 CuPdZn (2:1:2) 64.52 - 65.52 - - -
14 CuMnCo (1:0.5:0.5) 51.41 16.69 33.25 9.34 8.58 0.24
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A.M.ALIYEV et al.
Introducting different cations of transition and nontransition metals (Ni, Zn, Cu, Co, Cr, Mn, Fe, Mg, Mn, Bi, Pd and so on) into clinop-tilolite leads to the change of activity of this catalyst. It has been established that the effect of cations of these metals is not similar, since each of these cations behave differently in the reaction (Table 2). As a result of studies it is established that the highest yield of acrolein is observed on catalyst Ni-clinoptilolite containing Ni =1% (exper. No 6). Increase in concentration of this cation in the composition of catalyst decreases the yield of acrolein (exper. No 7, 8).
The influence of reaction temperature and volume rate on the yield of products on active catalyst was studied.
As Figure 1 shows when temperature is
increased from 320 to 380 C the yield of acrolein rises continuously and at 3800C reaches 80.93%, but at further increase in temperature it does not practically change. In studied temperature range at high temperature yield of other substances also increases.
When volume rate increases from 700 to 1400 h-1, the yield of acrolein and other reaction products decreases (Figure 2).
Thus, the studies showed the opportunity to convert propylene to acrolein on zeolite catalysts. We determined optimum composition of • 2+
cation (Ni=1%) introduced into clinoptilolite and optimum conditions for the reaction (T=3800C, Vo=700 h-1, C3H6:O2= 1.8:1) under which the yield of acrolein reaches 80.93%, in conversion of propylene it is 94.72%.
Fig. 1. Dependence of yield of A reaction products of acrolein (3), formaldehyde (2), carbon dioxide (1) and formic acid (4) on reaction temperature at molar ratio C3H6:O2=1.8:1 and Vq=700 h-1.
References
1. Iukelson I.I. Tekhnologiia osnovnogo organi-cheskogo sinteza. M.: Himiia, 1968. 507 s.
2. Kapkin V.D., Savinetckaia G.A., Chapurin V.I. Tekhnologiia organicheskogo sinteza M.: Himiia. 1987. S. 153-156.
Fig. 2. Effect of volume rate on the yield of A acrolein (3), formaldehyde (2), carbon dioxide (1) and formic acid (4) at molar ratio C3H6:O2=1.8:1 and T = 380qC.
3. Aliev A.M., Medzhidova S.M., Sarydzhanov A.A., Matiev K.I., Shabanova Z.A., Mamedova U.A., Aliev F.V., Nadzhaf-Kuliev U.M. Ionoobmennyi metod modifitcirovaniia tceolitov kationami me-tallov kak predelnaia model nanesennogo kata-lizatora // Azerb. xim. zhum 2011. № 4. S. 9-20.
METALSEOLIT KATALIZATORLAR UZORINDO PROPILENIN AKROLEINO OKSIDLO§DIRICI
ÇEVRiLMOSi
A.M.0liyev, U.M.Nacaf-Quliyev, T.i.Huseynova, V.M.Yariyev, E.M.Kazimova
Modifikasiya olunmuç seolit katalizatorlatn uzarinda propilenin akroleim oksidlaçdirici çevrilma reaksiyasinda katalitik aktivliklari tadqiq olunmuçdur. Muayyan olunmuçdur ki, Ni-klinoptilolit (Ni2+=1%) bu reaksiya uçun yuksak katalitik aktivlik gostarir. Aktiv katalizator uzarinda reaksiya mahsullannin çiximimn reaksiyanin temperaturu va hacmi suratdan asilligi ôyranilmiçdir.
Açar sozlar: oksidhçdirici çevrilma, akrolein, Ni-klinoptilolit, mordenit, aktivlik, NaY, NaX, NaA.
АЗЕРБАЙДЖАНСКИЙ ХИМИЧЕСКИЙ ЖУРНАЛ № 1 2019
ОКИСЛИТЕЛЬНОЕ ПРЕВРАЩЕНИЕ ПРОПИЛЕНА В АКРОЛЕИН НА МЕТАЛЦЕОЛИТНЫХ
КАТАЛИЗАТОРАХ
А.М.Алиев, У.М.Наджаф-Кулиев, Т.И.Гусейнова, В.М.Ярыев, Э.М.Кязимова
Исследована каталитическая активность модифицированных цеолитов в реакциях окислительного превращения пропилена в акролеин. Установлено, что №-клиноптилолит (1% №2+) проявляет высокую активность в рассматриваемой реакции. Изучено влияние температуры реакции и объёмной скорости на выход продуктов на активном катализаторе.
Ключевые слова: окислительное превращение, акролеин, Ы1-клиноптилолит, морденит, активность, ЫаУ, ЫаХ, ЫаА.
