Preparation of Mg-Al based solid base for the transesterification of propylene carbonate and methanol
-
摘要: 以共沉淀法制备了一系列不同价态过渡金属（Fe、Cu、Zr）改性的Mg-Al固体碱催化剂，考察了其对于甲醇与碳酸丙烯酯（PC）酯交换合成碳酸二甲酯的反应性能。采用XRD、N2吸附-脱附、FT-IR、XPS、CO2-TPD等手段对催化剂的物理化学性质进行了表征。结果表明，催化剂的碱强度、碱密度是影响催化活性的主要因素，不同价态过渡金属的加入可以调控Mg-Al固体催化剂的碱性。在考察的催化剂中，FeMgAl催化剂具有最高的表面碱密度，因此，表现出最好的催化性能。在温度为65 ℃、时间为4 h、甲醇与PC物质的量比为10：1、催化剂用量为4%的反应条件下，PC转化率可达66.2%。Abstract: A series of transition metals (Fe, Cu, Zr) modified Mg-Al solid bases were synthesized by co-precipitation method and characterized by XRD, N2 adsorption-desorption, FT-IR, XPS, CO2-TPD. The catalytic performances were investigated for the synthesis of dimethyl carbonate via transesterification of propylene carbonate (PC) and methanol. The results reveal that the surface basicity of the samples varies with the addition of different metals. The surface basic strength and density of the catalysts are the main factors affecting the catalytic activity. Among the catalysts studied, FeMgAl exhibits the highest surface basic density and thus shows the best catalytic performance. The conversion of PC can reach 66.2% under the temperature of 65 ℃, reaction time of 4 h, methanol/ester molar ratio of 10:1 and catalyst amount of 4% of the reactant.
-
Key words:
- transition metal /
- modification /
- Mg-Al based solid base /
- dimethyl carbonate /
- transesterification
-
图 7 表面中强碱密度之和β + γ随晶格氧O 1s的变化
Figure 7 Relationship between the basicity density and the O 1s binding energy of catalysts
图 8 PC转化率与催化剂碱性的关系
Figure 8 Relationship between PC conversion and basicity of catalysts
图 9 FeMgAl催化剂上(a)甲醇/PC物质的量比(b)反应时间(c)催化剂用量对催化活性的影响
Figure 9 Effect of reaction parameters on the catalytic activity over FeMgAl catalyst
(a): reaction temperature=65 ℃, reaction time=4 h, catalyst dose=4% of reactant; (b): reaction temperature=65 ℃, methanol/PC molar ration=10, catalyst dose=4% of reactant; (c): reaction temperature=65 ℃, reaction time=4 h, methanol/PC molar ration=10
表 1 催化剂的织构参数和碱性质
Table 1 Textural parameters and basic properties of catalysts
Catalyst Surface area
A/(m2·g-1)Pore volume
v/(cm3·g-1)Pore size
d/nmCO2 uptake /(mmol·g-1) CO2 uptake (×10-2 mmol·m-2) total α β+γ total MgAl 235 0.84 18.2 8.37 1.53 2.03 3.56 ZrMgAl 184 0.36 5.6 7.60 2.03 2.10 4.13 CuMgAl 72 0.34 17.1 4.05 3.01 2.61 5.62 FeMgAl 86 0.54 19.9 6.02 3.93 3.07 7.00 
下载: 导出CSV
表 2 催化剂的O 1s结合能和相对氧含量
Table 2 O 1s binding energy and relative oxygen content of catalysts
Catalyst Binding energy O 1sE/eV Surface oxygen molar ration of unit area /(×10-2) OⅠ OⅡ OⅢ OⅠ/O OⅡ/O OⅢ/O MgAl 530.3 531.6 532.4 0.18 0.12 0.12 ZrMgAl 530.2 531.4 532.2 0.26 0.18 0.11 CuMgAl 530.0 531.3 532.2 0.29 0.55 0.54 FeMgAl 529.9 531.2 532.0 0.30 0.56 0.30
下载: 导出CSV
表 3 催化剂的性能评价
Table 3 Catalytic performance for DMC synthesis
Catalyst Reaction time t/h Reaction temp. t/℃ PC con. x/% DMC sel. s/% Reference Blank 4.0 65 - - this work Al2O3 4.0 65 4.4 12.9 this work MgO 4.0 65 9.7 20.8 this work MgAl 4.0 65 10.7 20.9 this work ZrMgAl 4.0 65 51.6 81.9 this work CuMgAl 4.0 65 63.8 81.5 this work FeMgAl 4.0 65 66.2 82.6 this work Mg-Al-La 2.0 150 65.4 88.1 [18] MgO 6.0 140 55.0 15.0 [28] ZrO2 6.0 140 14.0 50.0 [28] Fe2O3 3.0 140 3.7 86.5 [13] CaO-ZrO2 2.0 140 57.0 - [10] Na/ZrO2 1.5 160 ~50.0 - [11] Amberlyst 39 wet 2.0 130 62.0 92.0 [12] Fe-Mn 3.0 140 49.4 96.1 [13]
下载: 导出CSV
-
[1] HUANG Z X, LIN Y X, WANG X D, YE C S, LI L. Optimization and control of a reactive distillation process for the synthesis of dimethyl carbonate[J]. Chin J Chem Eng, 2017, 25(8):1079-1090. doi: 10.1016/j.cjche.2017.03.039 [2] SONG Z W, SUBRAMANIAM B, RAGHUNATH V C. Kinetic study of CaO-catalyzed transesterification of cyclic carbonates with methanol[J]. Ind Eng Chem Res, 2018, 57(44):14977-14987. doi: 10.1021/acs.iecr.8b03837 [3] JOHANNES H, MATHIAS L, PHILIP L, ANDRZEJ G. Synthesis of dimethyl carbonate and propylene glycol by transesterification of propylene carbonate with methanol:Catalyst screening, chemical equilibrium and reaction kinetics[J]. Chem Eng Sci, 2013, 104:347-360. doi: 10.1016/j.ces.2013.09.007 [4] TAN H Z, WANG Z Q, XU Z N, SUN J, XU Y P, CHEN Q S, CHEN Y M, GUO G C. Review on the synthesis of dimethyl carbonate[J]. Catal Today, 2018, 316:2-12. doi: 10.1016/j.cattod.2018.02.021 [5] XUAN K, PU Y F, LI F, LUO J, ZHAO N, XIAO F K. Metal-organic frameworks MOF-808-X as highly efficient catalysts for direct synthesis of dimethyl carbonate from CO2 and methanol[J]. Chin J Catal, 2019, 40(4):553-566. http://d.old.wanfangdata.com.cn/Periodical/cuihuaxb201904009 [6] PICHAYAPAN K, VARONG P, RAFIQUL G, SUTTICHAI A. Techno-economic evaluation of different CO2-based processes for dimethyl carbonate production[J]. Chem Eng Res Des, 2015, 93:496-510. doi: 10.1016/j.cherd.2014.07.013 [7] LOE J G, AZUARA A J, ALBERO J S, ESCRIBANO A S, FERNÁNDEZ E V R. Layered double hydroxides as base catalysts for the synthesis of dimethyl carbonate[J]. Catal Today, 2017, 296:254-261. doi: 10.1016/j.cattod.2017.04.047 [8] 肖远胜, 张雪峥, 张书笈, 赵维君.酯交换法同时合成碳酸二甲酯及乙二醇[J].精细石油化工, 2000, (2):1-3. http://d.old.wanfangdata.com.cn/Periodical/jxsyhg200002001XIAO Yuan-sheng, ZHANG Xue-zheng, ZHANG Shu-ji, ZHAO Wei-jun. The simultaneous synthesis of dimethyl carbonate and ethylene glycol by transesterification[J]. Spec Petrochem, 2000, (2):1-3. http://d.old.wanfangdata.com.cn/Periodical/jxsyhg200002001 [9] LEE K H, LEE S, SHIN D, HAHM H S. Dimethyl carbonate synthesis via transesterification of ethylene carbonate and methanol using ionic liquid catalysts immobilized on mesoporous cellular foams[J]. Res Chem Intermed, 2016, 42(1):109-121. doi: 10.1007/s11164-015-2396-4 [10] WANG H, WANG M H, ZHANG W Y, ZHAO N, WEI W, SUN Y H. Synthesis of dimethyl carbonate from propylene carbonate and methanol using CaO-ZrO2 solid solutions as highly stable catalysts[J]. Catal Today, 2006, 115(1/4):107-110. doi: 10.1016-j.cattod.2006.02.031/ [11] LIU S G, HUANG S Y, GUAN L X, LI J P, ZHAO N, WEI W, SUN Y H. Preparation of a novel mesoporous solid base Na-ZrO2 with ultrahigh thermal stability[J]. Microporous Mesoporous Mater, 2007, 102(1/3):304-309. https://www.sciencedirect.com/science/article/abs/pii/S138718110700008X [12] PYRLIK A, HOELDERICH W F, MVLLER K, ARLT W, STRAUTMANN J, KRUSE D. Dimethyl carbonate via transesterification of propylene carbonate with methanol over ion exchange resins[J]. Appl Catal B:Environ, 2012, 125:486-491. doi: 10.1016/j.apcatb.2011.09.033 [13] SONG Z W, SUBRAMANIAM B, CHAUDHARI R V. Transesterification of propylene carbonate with methanol using Fe-Mn double metal cyanide catalyst[J]. ACS Sustainable Chem Eng, 2019, 7(6):5698-5710. doi: 10.1021/acssuschemeng.8b04779 [14] JONGGOL T, PANNAPAT C, MANAT P. Synthesis, characterization, and activity in transesterification of mesoporous Mg-Al mixed-metal oxides[J]. Microporous Mesoporous Mater, 2010, 128(1/3):41-47. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=994b4bdc0b9165c716f760fac9dc60b8 [15] PRAKRUTHI H R, CHANDRASHEKARA B M, PRAKASH B S J, BHAT Y S. Microwave rehydrated Mg-Al-LDH as base catalyst for the acetalization of glycerol[J]. Catal Sci Technol, 2015, 5(7):3667. doi: 10.1039/C5CY00347D [16] OLGA V L, KARINA V V, PAVLO I K, NINA V V, DMYTRO Y B, IVAN K, TOMAŽČ, SERGIY O S, SVITLANA M O. Successive vapour phase Guerbet condensation of ethanol and 1-butanol over Mg-Al oxide catalysts in a flow reactor[J]. Appl Catal A:Gen, 2019, 588:117265. doi: 10.1016/j.apcata.2019.117265 [17] UNNIKRISHNAN P, SRINIVAS D. Calcined, rare earth modified hydrotalcite as a solid, reusable catalyst for dimethyl carbonate synthesis[J]. Ind Eng Chem Res, 2012, 51(18):6356-6363. doi: 10.1021/ie300678p [18] SUN J, YANG J Y, LI S P, XU X R. Basicity-FAME yield correlations in metal cation modified MgAl mixed oxides for biodiesel synthesis[J]. Catal Commun, 2014, 52:1-4. doi: 10.1016/j.catcom.2014.03.023 [19] WANG D F, ZHANG X L, CONG X S, LIU S F, ZHOU D G. Influence of Zr on the performance of Mg-Al catalysts via hydrotalcite-like precursors for the synthesis of glycerol carbonate from urea and glycerol[J]. Appl Catal A:Gen, 2018, 555:36-46. doi: 10.1016/j.apcata.2018.02.009 [20] WANG D F, ZHANG X L, LIU C L, CHENG T T, WEI W. SUN Y H. Transition metal-modified mesoporous Mg-Al mixed oxides:Stable base catalysts for the synthesis of diethyl carbonate from ethyl carbamate and ethanol[J]. Appl Catal A:Gen, 2015, 505:478-486. doi: 10.1016/j.apcata.2015.04.034 [21] YAN T T, BING W H, LI Y W, YANG Y S, CUI G Q, YANG L, WEI M. Acid-base sites synergistic catalysis over Mg-Zr-Al mixed metal oxide toward synthesis of diethyl carbonate[J]. RSC Adv, 2018, 8(9):4695. doi: 10.1039/C7RA13629C [22] HOLGADO M J, RIVES V, SAN ROMÁN M S. Characterization of Ni-Mg-Al mixed oxides and their catalytic activity in oxidative dehydrogenation of n-butane and propene[J]. Appl Catal A:Gen, 2001, 214(2):219-228. doi: 10.1016/S0926-860X(01)00496-3 [23] LIN L, VITTAYAPADUNG S, LI X Q, JIANG W W, SHEN X Q. Synthesis of magnetic calcium oxide hollow fiber catalyst for the production of biodiesel[J]. Environ Prog Sustainable Energy, 2013, 32(4):1255-1261. http://cn.bing.com/academic/profile?id=8ce68f8031bdd16c608aadc12ae40449&encoded=0&v=paper_preview&mkt=zh-cn [24] PRAVEEN K, VIMAL C S, INDRA M M. Dimethyl carbonate synthesis from propylene carbonate with methanol using Cu-Zn-Al catalyst[J]. Energy Fuels, 2015, 29(4):2664-2675. doi: 10.1021/ef502856z [25] 廖云辉.钙基固体碱上碳酸丙烯酯与甲醇合成碳酸二甲酯的研究[D].太原: 中国科学院山西煤炭化学研究所, 2018.LIAO Yun-hui. Ca-based solid base for the dimethyl carbonate synthesis from propylene carbonate and methanol[D]. Taiyuan: Institute of Coal Chemistry, Chinese Academy of Science, 2018. [26] 王慧.无机复合固体碱的制备和稳定化及其在酯交换合成碳酸二甲酯等绿色催化过程中的应用[D].太原.中国科学院山西煤炭化学研究所, 2006.WANG Hui. Preparation, characterization of highly stable solid base and its application in the synthesis of dimethyl carbonate by transesterification[D]. Taiyuan: Institute of Coal Chemistry, Chinese Academy of Science, 2006. [27] NAYANA N, ASHUTOSH K. Selective synthesis of dimethyl carbonate via transesterification of propylene carbonate with methanol catalyzed by bifunctional Li-Al nano-composite[J]. Chem Select, 2019, 4(29):8574-8583. http://cn.bing.com/academic/profile?id=8441c012b168fd8abc58bd2848a54037&encoded=0&v=paper_preview&mkt=zh-cn [28] RAQUEL J, AVELINO C, HERMENEGILDO G. Gold nanoparticles promote the catalytic activity of ceria for the transalkylation of propylene carbonate to dimethyl carbonate[J]. Green Chem, 2009, 11(7):949-952. doi: 10.1039/b902850a -
点击查看大图
图(10) / 表(3)
计量
- 文章访问数: 123
- HTML全文浏览量: 48
- PDF下载量: 18
- 被引次数: 0
