Biodiesel production based on crude oils using zinc-based catalysts Shuli Yan

Outline Background

Literature review

Objective

Experiment

Reference Zinc-based catalysts in transesterification Zinc-based catalysts in esterification Zinc-based catalysts in hydrolysis

Background Biodiesel

Background Advantages of using biodiesel Biodegradable Low emission profile Low toxicity Better fuel Efficiency High lubricity

BackgroundHigh production Cost Refined vegetable oils( soybean oil $0.35/lb)

FFA content is lower than 0.5 % (wt) Water content is lower than 0.06% (wt) Crude oils and yellow grease( about 70 % of refined oils)

FFA content is in the range of 0.5 ~ 15 % (wt) Water content is higher than 0.06% (wt)

Background Long production process (A two-step method)

Background

Simultaneous transesterification and esterification Minimizing hydorlysis Developing a heterogeneous catalyst with high activity processing feedstock with high FFA and water

Outline Background

Literature review

Objective

Experiment

Reference Zinc-based catalysts in transesterification Zinc-based catalysts in esterification Zinc-based catalysts in hydrolysis

Literature review

Literature reviewZinc-based catalysts in transesterificationSuppes et al: Zinc Oxide and zinc carbonate, 120 oC, 24hr, yield 80 %

Xie et al: KF/ZnOLi et al: I2/ZnO

Sreeprasanth et al: Fe-Zn oxidesEsterfipH process: Al-Zn oxidesThe activity of catalyst is related with its basicityThe activity of catalyst is related with its acidity

Literature review Zinc-based catalysts in esterification

Literature review Zinc-based catalysts in hydrolysis Markley, K. S. In Fatty Acids, 2nd ed.; Markley, K. S., Ed.; Interscience Publishers Ltd.: London, 1961; Part 2, Chapters 8 and 9. Hui, Y.H.; Bailey's industrial oil and fat products, 4th ed. (In Chinese); Shu, W. Y.; Manual of oil technology; (In Chinese);

Literature review My previous work

Literature review My previous work

Literature review My previous work

Outline Background

Literature review

Objective

Experiment

Reference Zinc-based catalysts in transesterification Zinc-based catalysts in esterification Zinc-based catalysts in hydrolysis

ObjectiveThe overall objective is to develop an effective zinc-based catalyst for both transeseterification and esterification, while limiting hydrolysis of oil.This zinc-based catalyst will be used directly to catalyze some crude oils which contain FFA and water in the range of 0.5 ~ 15 % for the purpose of biodiesel production.

ObjectiveTwo aspects: Confirm the reaction pathway for methyl esters production

Objective Enhance the active sites on the surface of zinc-based catalysts By alloying (i.e. La2O3) Preparation conditionsCalcination temperatureMolar ratioPreparation method

Outline Background

Literature review

Objective

Experiment

Reference Zinc-based catalysts in transesterification Zinc-based catalysts in esterification Zinc-based catalysts in hydrolysis

Experiment Synthesis of zinc-based catalysts Precipitation method Zn: La = 1:0, 1:1, 3:1, 9:1, 0:1 Drying condition: 100 oC for 8 hr. Calcining condition: 200 ~700 oC for 8hr

Experiment Characterization of zinc-based catalysts Surface composition (AES and XPS) Bulk composition (XRD and AAS) Surface area (BET) Pore structure ( mercury porosimetry )

ExperimentActivity test of zinc-based catalysts Transesterification of refined oil with methanol

Esterification of oleic acid with methanol

Hydrolysis of refined oil, hydrolysis of methyl esters

Simultaneous catalysis process, i.e. using zinc catalysts in some natural crude oils, refined oil with FFA addition, refined oil with water addition, refined oil with both FFA and water addition, respectively.

ExperimentActivity test of zinc-based catalysts Temperature(100 ~ 230 oC), Time(0 ~ 6 hr), Molar ratio of methanol to oil(3:1 ~60:1), Catalyst dosage(0 ~ 25 % wt. ), Particle size of catalyst(10 ~ 200 mesh), Stir speed (100 ~ 600 rpm )At elevated temperature and pressure in a batch reactor No mass transfer limitationReaction conditions:

Summary

To understand the impact of bulk structure, surface structure, and the interaction between zinc oxide and support on the yield of methyl esters.

References[1] Clark S. J., Wagner L., Schrock MD. Methyl and ethyl esters as renewable fuels for diesel engines. J. Am. Oil Chem. Soc. 1984, 61, 1632-1638.[2] Muniyappa PR, Brammer SC, Noureddini H. Improved conversion of plant oils and animal fates into biodiesel and co-product. Bioresour. Technol. 1996, 6, 19-24.[3] Nelson, R. G., Hower, S. A. Potential feedstock supply and costs for biodiesel production. In Bioenergy 94, Proceedings of the Sixth National Bioenergy Conference, Reno/Sparks, NV, 1994[4] Canakci, M.; Gerpen, J. V. Biodiesel production from oils and fats with high free fatty acids. Trans. ASAE 2001, 44, 1429-1436.[5] Kusdiana, D.; Saka, S. Effects of water on biodiesel fuel production by supercritical methanol treatment. Bioresour. Technol. 2004, 91, 289-295. [6] Saka, S.; Kusdiana, D.; Minami, E. Non-catalytic biodiesel fuel production with supercritical methanol technologies. J. Sci. Ind. Res. 2006, 65, 420-425.[7] Wang C.; Sun Y.; Hu L., Poly (ethylene naphthalate) formation 1. Transesterification of dimethylnaphthalate with ethylene glycol. J. Polymer. Res. 1994, 1, 131139.

References[12] J. Chen, L. Chen, J. Appl. Polym. Sci. 73 (1999) 3540.[13] E. Santacesaria, F. Trulli, L. Minervini, M. Di Serio, R. Tesser, S. Contessa, J. Appl. Polym. Sci. 54 (1994) 13711384.[14] C. Wang, Y. Sun, L. Hu, J. Polym. Res. 1 (1994) 131139.[15] R. Nava, T. Halachev, R. Rodriguez, V.M. Castano, Catal. A: Gen. 231, (2002) 131149.[16] R. Nava, T. Halachev, R. Rodriguez, V.M. Castano, Microporous Mesoporous, Mater. 78 (2005) 9196.[17] R. Aafaqi, A.R. Mohamed, S. Bhatia, J. Chem. Technol. Biotechnol. 79, (2004) 11271134.[18] M. Adam and Szela g H. Ind. Eng. Chem. Res. 43, (2004), 7744-7753[19] Pouilloux, Y.; Metayer, S.; Barrault, J. Synthesis of Glycerol Monooctadecanoate from Octadecanoic Acid and Glycerol. Influence of Solvent on the Catalytic Properties of Basic Oxides.C. R. Acad. Sci. Paris, Ser. IIc, Chim. 2000, 3, 589.[20] Szela g, H.; Macierzanka, A. Tenside Surf. Det. 2001, 38, 377.

Thank you!

Biodiesel is a mixture of fatty acid esters of low alkyl-chain alcohols. Biodiesel is generally obtained by transesterification of refined vegetable oils with methyl alcohol. Analysis from Nelson et al indicates that the cost of the refined oil used to produce biodiesel affects the cost of biodiesel up to 80 %. Therefore, less-expensive raw materials are preferred. Crude vegetable oil, which contains some FFA and water, is a promising alternative to the refined oil for biodiesel production. A two-step method, first using acid catalysis and then using base catalysis, is frequently reported for converting crude oil into biodiesel. In comparison to the above homogeneous catalysts, solid catalysts have many superiorities. For instance, solid catalysts are less corrosive; they can be separated easily from reaction products, therefore the production process is simplified and quite a few steps in Figure 2 can be eliminated. For crude vegetable oil, the content of FFA and water is in the range of 0~5%. Therefore, it was suggested that three major reactions took place in this system. Zinc catalyst has been used in the number of transesterification, esterification and hydrolysis reactions at high temperature, in the form of unsupported or supported catalysts. Thus, our plan is to obtain an effective zinc catalyst which function simultaneously in natural oil transesterification, fatty acid esterification and ester hydrolysis for the purpose of biodiesel production.

Recently, many researchers paid much attention to screening an effective solid catalyst in transesterification of refined oil into methyl esters. However, to my knowledge so far there is still no effective heterogeneous catalyst reported to be tolerant to FFA and water. In diverse esterification reactions, zinc catalysts have been extensively studied and even used in industrial Zinc oxide is a traditional catalyst for hydrolysis of natural oil for fatty acid production, and the related technologies have been written in schoolbooks In my previous work, a number of transition metal oxides has been screened for refined oil transeseterfication with methanol. We found that pure ZnO shows a relatively high catalytic activity for this reaction in comparison to other transit metal oxides. This result is consistent with Suppes and Karmee. In my previous work, a wide screen has been performed on some transition metal oxides for refined oil transeseterfication with methanol. We found that pure ZnO shows a relatively high catalytic activity for this reaction in comparison to other transit metal oxides. This result is consistent with Suppes [and Karmee. In my previous work, a wide screen has been performed on some transition metal oxides for refined oil transeseterfication with methanol. We found that pure ZnO shows a relatively high catalytic activity for this reaction in comparison to other transit metal oxides. This result is consistent with Suppes [and Karmee. However, there is no further work done on the catalytic activities of pure ZnO in esterification and hydrolysis reactions. Figure 5 is about three reactions involved in the treatment of crude oils with methanol containing some water and FFA.

According to selecting the suitable additives and the optimal preparation method for catalyst, we can tune the ability of active sites to adsorb reactant molecule and change the catalyst activity.The experiments include synthesis, characterization, and activity test of zinc catalysts. Since the preparation process for zinc catalyst has substantial effects on the interactions between active component and support, after selecting the right components of heterogeneous catalyst, we shall investigate three preparation methods for solid base catalysts, i.e. coprecipitation, impregnation and deposition precipation. This part is closely related to the 3.1 and 3.2 parts