1、1,Biodiesel Production by Simultaneous Transesterification and Esterification,Shuli Yan, Manhoe Kim, Steve O. Salley, John Wilson, and K. Y. Simon NgNational Biofuels Energy Laboratory NextEnergy/Wayne State University Detroit, MI 48202,Present at AIChE Meeting Nov. 20, 2008,2,IntroductionExperiment
2、 Results and DiscussionConclusion,Biodiesel Traditional Processes for Biodiesel Production Literature Review,Transesterification Esterification Hydrolysis Effects of FFA and Water Effect of Catalyst Structure,Outline,3,Introduction,Biodiesel,A mixture of fatty acid esters Derived from vegetable oils
3、, animal fats, waste oils,4,Introduction,Biodiesel - Advantages,BiodegradableLow emission profileLow toxicityEfficiencyHigh lubricity,99 00 01 02 03 04 05 06,5,Introduction,Traditional Processes for Biodiesel Production,Refined oils as feedstock (food-grade vegetable oils) Homogeneous strong base or
4、 acid catalysts (NaOH, H2SO4),FFA content is lower than 0.5 % (wt)Water content is lower than 0.06% (wt)High price,Highly corrosiveLong oil pretreatment processLong product purification process,Large amount of waste waterLong time for phase separationHigh process cost,6,Introduction,Decrease of Feed
5、stock CostDecrease of Process Cost,Using unrefined or waste oils as feedstock Crude vegetable oils, recycled cooking oils, trap grease etc.,Simplifying the pretreatment and reaction process Simultaneous catalysis of transesterification and esterificationSimplifying the product purification processRe
6、place homogeneous catalysts by heterogeneous catalysts,7,Introduction,Effects of FFA and water,Figure 1 Effects of FFA and water on traditional processes,Decrease,Decrease,8,Literatures,ZnO ZnO, ZnO-Al2O3, I2/ZnO Contain base or acid sites Low activity and unstable, low tolerance to water and FFA La
7、2O3 La2O3/TiO2, La2O3-Ni/MgO Structure promoter, increase surface base site, thermal stability No reports in biodiesel production Mixed ZnO- La2O3 System Homogeneous Co-precipitation Zn:La = 1:0 1:1 3:1 9:1 0:1,9,Unrefined or waste oils,Figure 1 Reactions involved in the treatment of crude oils usin
8、g Zn3La1 catalyst.,Transesterification Esterification Hydrolysis,10,Develop a new class of heterogeneous catalysts High tolerance to water and FFA Simultaneously catalyze transesterification and esterification, while minimizing hydrolysis Process crude oils directly,Objective,11,Experiment,Homogeneo
9、us Co-precipitation Method,Prepare mixture solutions of Zn(NO3)2 , La(NO3)3 and urea in appropriate ratios Heat to 100 oC and hold for 6 hr Stirred with magnetic stirrer Filter/unfilter Dry at 150 oC for 8 hr Use step-rise calcination method to control the catalyst morphology,12,Experiment,ReactorPr
10、oduct analysis,TransesterificationEsterification Hydrolysis,GC-MS Karl Fischer (Water Content)Titration (Fatty Acid Content),Parr 4575 HT/HP Reactor (500 ml, 500 C, 34 MP),13,Catalyst characterization,XRD,Figure 13 XRD patterns of zinc and lanthanum mixed metal oxides,ZnO, La2CO5 LaOOH,14,Catalyst C
11、haracterization,Table 1 XRD Structures of Zinc and Lanthanum Mixtures,15,XPS,Lewis Base Site,Lewis Acid Site,Total Basic and Acid Site,Table 2 XPS data of Zinc and Lanthanum Mixtures,16,Metal oxides in transesterification,Figure 1 Transesterification activities of Zn10La0, Zn3La1 and Zn0La10 as a fu
12、nction of temperature.,170 oC,Mixed oxide shows the highest activity,17,Metal oxides in transesterification,Figure 2. Transesterification activities of Zn10La0, Zn9La1, Zn3La1, Zn1La1 and Zn0La10 at 200 oC,18,Figure 3 Effect of initial oil concentration on transesterification.,Metal oxides in transe
13、sterification,19,Metal oxides in transesterification,Figure 4 Effect of reaction temperatures,Eappl = 91.28 KJ mol-1,a = 1.08,20,Metal oxides in esterification,Figure 6 Esterification of oleic acid with methanol as a function of reaction temperature,140 oC,21,Metal oxides in esterification,Figure 8
14、Process using refined oil with 5 % FFA addition,Figure 7 Yield of oleic methyl ester at 200 oC,22,Metal oxides in hydrolysis,Figure 8 Hydrolysis activities of Zn3La1 as a function of temperature.,220 oC,X,23,Metal oxides in hydrolysis,Oil containing 5.30 % water and 94.70 % triglycerides,Figure 9 Wa
15、ter content changes during the process using refined oil with 5 % water addition,24,Effect of FFA on biodiesel production,Figure 10 Effect of FFA additions on transesterification. a: Yield of FAME in the presence of different FFA addition; b: Effect of FFA content on equilibrium yield of FAME;,Decre
16、ase,25,Effect of water on biodiesel production,Figure 10 Effect of water addition on transesterification. a: Yield of FAME in the presence of different water addition; b: Effect of water addition on equilibrium yield of FAME;,Decrease,26,Using unrefined and waste oils,Figure 11 Using some unrefined
17、or waste oils for biodiesel production,27,Catalyst Life,In Batch Reactor,Figure 4 Yield of FAME vs Reaction Times,Figure 5 Yield of FAME vs Reaction Times,In Continuous Reactor,the catalyst reused 17 times,the catalyst runs 32.5 days,28,Conclusion,A single-step method using unrefined oils and hetero
18、geneous zinc and lanthanum mixed oxides Oil transesterification reaction and FFA esterification reaction Minimizing hydrolysis of oil and hydrolysis of biodiesel A temperature window, 170 220 oC A strong interaction between Zn and La species La acts as a diluent of the matrix, promoting ZnO particle distribution, increasing the surface basic and acid sites, and enhancing activity of transesterification and esterification,29,Acknowledgement,Financial support from the Department of Energy (DE12344458) and Michigans 21st Century Job Fund is gratefully acknowledged.,
