• Vol 11, No 3 (2020)
  • Chemical Engineering

Intensification of Synthesis of Fatty Acid Isopropyl Ester using Microwave

Amrina Maulida, Zahrati Zahrati, Hilyati Kamila, Teuku Mukhriza, Asri Gani, Muhammad Dani Supardan

Corresponding email: m.dani.supardan@unsyiah.ac.id


Cite this article as:
Maulida, A., Zahrati, Z., Kamila, H., Mukhriza, T., Gani, A., Supardan, M.D., 2020. Intensification of Synthesis of Fatty Acid Isopropyl Ester using Microwave. International Journal of Technology. Volume 11(3), pp. 492-500

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Amrina Maulida Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Zahrati Zahrati Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Hilyati Kamila Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Teuku Mukhriza Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Asri Gani Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Muhammad Dani Supardan Department of Chemical Engineering, Engineering Faculty, Universitas Syiah Kuala, Jl. Syech Abdurrauf No. 7, Darussalam, Banda Aceh, 23111, Indonesia
Email to Corresponding Author

Abstract
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Fatty acid isopropyl ester is one of the derivative products from vegetable oils such as crude palm oil (CPO). Chemically, fatty acid isopropyl esters can be synthesized from oils or vegetable fats with isopropanol using inorganic catalysts. The purpose of this research was to intensify the process of synthesis of fatty acid isopropyl esters from CPO using microwaves. Research variables used were CPO to isopropanol molar ratios of 1:3, 1:5, 1:7, 1:9, 1:11, and 1:13; reaction times of 1, 3, and 5 minutes; and KOH catalyst concentrations of 0.10, 0.15, 0.20, and 0.30 (%-w of CPO). The experimental result showed that the process variables affected the yield of fatty acid isopropyl esters. The highest yield obtained (80.5%) was found at molar ratio of CPO to isopropanol of 1:11, catalyst concentration of 0.2% (%-w of CPO), and reaction time of 5 minutes. With the same conditions, a 72.2% yield was obtained in 150 minutes using conventional transesterification. Fourier transform infrared analysis showed some specific functional groups in fatty acid isopropyl esters. In addition, viscosity, density, and acid number of fatty acid isopropyl esters produced conformed to the Indonesian National Standard (SNI) No. 7182-2015.

CPO; Fatty acid isopropyl esters; Microwave; Transesterification

Introduction

The use of vegetable oil is highly prevalent in Indonesia due to its abundant availability. The development of oleochemical industries that produce derivative products from vegetable oils is still largely at a prospective stage and needs to be strengthened to increase the economic value of the resource. Following such development, it is hoped that the derivative product of vegetable oil will not only meet domestic needs but will also become an important Indonesian export commodity.

One of the potential derivative products of vegetable oil is fatty acid isopropyl esters. Fatty acid isopropyl esters are in great demand because these fatty acids can be used as raw materials for various products, such as cosmetics, foods, pharmaceuticals, bio-lubricants, and bio-solvents (Seo et al., 2018). Crude palm oil (CPO) is one of the potential raw materials that can be used for the production of fatty acid isopropyl esters. At present, Indonesia is the largest producer and exporter of CPO in the world. However, the economic value obtained from CPO is still not optimal. The processing of CPO to its derivative products, which have a higher selling value, must be conducted to optimize the economic value of CPO in Indonesia.

Several technological processes for the production of  fatty acid alkyl esters have been developed. The chemical transesterification process is the most widely used process for the synthesis of fatty acid alkyl esters such as fatty acid isopropyl esters (Supardan et al., 2017; Cercado et al., 2018). However, chemical transesterification using the conventional process has some shortcomings such as long reaction times and considerably severe operating conditions making such reaction an energy-intensive process. Alternative processes, such as the use of microwaves (Ye et al., 2016) and ultrasonic and hydrodynamic cavitation (Laosuttiwong et al., 2018) can be used to intensify the fatty acid alkyl ester production process.

Microwaves are a non-conventional energy source, which has been used for a variety of applications including chemical synthesis. Several researchers have reported the advantages of using microwaves compared to conventional methods, including Encinar et al. (2012) and Teo and Ani (2014). The intensification of the transesterification process using microwaves was had also been explored in prior research. For example, Dehghan et al. (2019) reported the use of microwaves to accelerate the transesterification of inedible olive oil for biodiesel production, and Yu et al. (2017) used the synergistic microwave-ultrasonic irradiation for the transesterification of soybean oil.

This study aims to intensify the synthesis process of fatty acid isopropyl ester from CPO using KOH as an alkaline catalyst through the use of a built-in microwave. Presently, there is limited information in the published literature on the intensification process concerning the processing of CPO to its derivative products. To address this research gap, we will compare the performance of the synthesis process using microwaves to that of the conventional processes using stirrers. 

Conclusion

The use of microwaves has been shown to intensify the synthesis process of fatty acid isopropyl esters. The highest yield of 80.5% of fatty acid isopropyl esters was obtained at the following condition: CPO to isopropanol molar ratio 1:11, catalyst concentration 0.2%, and reaction time 5 minutes. The use of microwaves provided a higher yield of fatty acid isopropyl esters than conventional transesterification processes. The results of the FTIR analysis showed several specific functional groups in fatty acid isopropyl esters produced. The results of testing the characteristics of fatty acids isopropyl ester showed that viscosity, density, and acid number met the SNI No. 7182-2015 standard.

Acknowledgement

We would like to acknowledge the contributions of The Ministry of Research, Technology, and Higher Education of the Republic of Indonesia, which has funded this research (No. 61/UN11.2/PP/SP3/2019), and the Chemical Engineering Department of Universitas Syiah Kuala, which provided the research facility.

References

Cercado, A.P., Ballesteros, F.C., Capareda, S.C., 2018. Biodiesel from Three Microalgae Transesterification Processes using Different Homogenous Catalysts. International Journal of Technology, Volume 9(4), pp. 645–651

Chuah, L.F., Suzana, Y., Abdul, R.A.A., Awais, B., Jiri, J.K., Zamri, M.A., 2015. Intensification of Biodiesel Synthesis from Waste Cooking Oil (Palm Olein) in a Hydrodynamic Cavitation Reactor: Effect of Operating Parameters on Methyl Ester Conversion. Chemical Engineering and Processing, Volume 95, pp. 235–240

Dehghan, L., Golmakani, M.T., Hosseini, S.M.H., 2019. Optimization of Microwave-assisted Accelerated Transesterification of Inedible Olive Oil for Biodiesel Production. Renewable Energy, Volume 138, pp. 915922

Elkady, M.F., Ahmed Z., Ola, B., 2015. Production of Biodiesel from Waste Vegetable Oil via KM Micromixer. Journal of Chemistry, Volume 2015, pp. 1–9

Encinar, J.M., Gonzalez, J.F., Martinez, G., Sanchez, N., Pardal, A., 2012. Soybean Oil Transesterification by the Use of a Microwave Flow System. Fuel, Volume 95, pp. 386–393

Hidayat, A., Mukti, N.I.F., Handoko, B., Sutrisno, B., 2018. Biodiesel Production from Rice Bran Oil over Modified Natural Zeolite Catalyst. International Journal of Technology. Volume 9(2), pp. 400–411

Helmiyati, Anggraini, Y., 2019. Nanocomposite Comprising Cellulose and Nanomagnetite as Heterogeneous Catalysts for the Synthesis of Biodiesel from Oleic Acid. International Journal of Technology, Volume 10(4), pp. 798–807

Laosuttiwong, T., Ngaosuwan, K., Kiatkittipong, W., Wongsawaeng, D., Kim-Lohsoontorn, P., Assabumrungrat, S., 2018. Performance Comparison of Different Cavitation Reactors for Biodiesel Production via Transesterification of Palm Oil. Journal of Cleaner Production, Volume 205, pp. 1094–1101

Lidstrom, P., Tiarney, J., Wathey, B., Westman, J., 2001. Microwave Assisted Organic Synthesis-A Review. Tetrahedron, Volume 57(45), pp. 92259283

Mahlinda, Supardan M.D., Husin H., Riza M., Muslim A., 2017. A Comparative Study of Biodiesel Production from Screw Pine Fruit Seed: Using Ultrasound and Microwave Assistance in In-situ Transesterification. Journal of Engineering Science and Technology, Volume 12(12), 34123425

Milano, J., Hwai, C.O., Masjuki, H.H., Silitonga, A.S., Wei, H.C., Kusumo, F., Dharma, S., Sebayang, A.H., 2018. Optimization of Biodiesel Production by Microwave Irradiation-assisted Transesterification for Waste Cooking Oil-Calophyllum Inophyllum Oil via Response Surface Methodology. Energy Conversion and Management, Volume 158, pp. 400–415

Nayak, S.N., Bhasin, C.P., Nayak, M.G., 2019. A Review on Microwave-assisted Transesterification Processes using Various Catalytic and Non-catalytic Systems. Renewable Energy, Volume 143, pp. 1366–1387

Patil, P.D., Gude, V.G., Camacho, L.M., Deng, S., 2010. Microwave-assisted Catalytic Transesterification of Camelina Sativa Oil. Energy & Fuels, Volume 24(2), pp. 12981304

Panadare, D.C., Rathod, V.K., 2017. Microwave Assisted Enzymatic Synthesis of Biodiesel with Waste Cooking Oil and Dimethyl Carbonate. Journal of Molecular Catalysis B: Enzymatic, Volume 133(S1), pp. S518–S524

Satriana, Arpi, N., Supardan, M.D., Gustina, R.T., Mustapha, W.A.W., 2018. Low-Temperature Glycerolysis of Avocado Oil. In: AIP Conference Proceedings, Volume 1940, 020100

Seo, E.J., Yeon, Y.J., Seo, J.H., Lee, J.H., Bongol, J.P., Oh, Y., Moon Park, J., Lim, S.M., Lee, C.G., Park, J.B., 2018. Enzyme/whole-cell Biotransformation of Plant Oils, Yeast Derived Oils, and Microalgae Fatty Acid Methyl Esters into n-nonanoic Acid, 9-hydroxynonanoic acid, and 1,9-nonanedioic Acid. Bioresource Technology, Volume 251, pp. 288–294

Supardan, M.D., Fahrizal, Moulana, R., Safrida, D., Satriana, Mustapha, W.A.W., 2017. Optimization of Process Parameter Conditions for Biodiesel Production by Reactive Extraction of Jatropha Seeds. Journal of Engineering Science and Technology, Volume 12(3), pp. 847–859

Syamsuddin, Y., Murat, M.N., Hameed, B.H., 2016. Synthesis of Fatty Acid Methyl Ester from the Transesterification of High- and Low-acid-content Crude Palm Oil (Elaeis guineensis) and Karanja oil (Pongamia pinnata) over a Calcium Anthanum Aluminum Mixed-oxides Catalyst. Bioresource Technology, Volume 214, pp. 248–252

Teo, C.L., Ani, I., 2014. Evaluation of Direct Transesterification of Microalgae using Microwave Irradiation. Bioresource Technology, Volume 174, pp. 281–286

Thoai, D.N., Chanakaewsomboon, I., Prasertsit, K., Photaworn, S., Tongurai, C., 2019. A Novel Inspection of Mechanisms in Conversion of Refined Palm Oil to Biodiesel with Alkaline Catalyst. Fuel, Volume 256, pp. 1–9

Ye, W., Yujie, G., Hui, D., Mingchao, L., Shejiang, L., Xu, H., Jinlong, Q., 2016. Kinetics of Transesterification of Palm Oil under Conventional Heating and Microwave Irradiation, using CaO as Heterogeneous Catalyst. Fuel, Volume 180, pp. 574–579

Yu, G.W., Nie, J., Lu, L.G., Wang, S.P., Li, Z.G., Lee, M.R., 2017. Transesterification of Soybean Oil by using the Synergistic Microwave Ultrasonic Irradiation. Ultrasonics Sonochemistry, Volume 39, pp. 281–290

Yusuff, A.S., Adeniyi, O.D., Olutoye, M.A., Akpan, U.G., 2018. Development and Characterization of a Composite Anthill-chicken Eggshell Catalyst for Biodiesel Production from Waste Frying Oil. International Journal of Technology, Volume 9(1), pp. 110119