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Esterification of α-Pinene from Turpentine Oil Using Natural Zeolite Catalyst

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Turpentine is one of the oils obtained from pine trees with >80% α-pinene composition. Turpentine oil has a high selling value by making α-pinene derivative through an esterification reaction. The esterification reaction was carried out with time variation and reaction temperature using natural zeolite. Characterization of the catalyst using X-Ray Diffraction, IR spectroscopy and Scanning Electron Microscopy. The esterification reaction product was analyzed by IR spectroscopy, and Gas Chromatography - Mass Spectroscopy. The main product of α-pinene esterification reaction was α-terpinyl acetate (21.40%), and the selectivity of 28.87 %, produced at 40ºC for 3 hours.
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Esterification of α-Pinene from Turpentine Oil Using Natural Zeolite
Catalyst
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
Esterification of α-Pinene from Turpentine Oil Using Natural
Zeolite Catalyst
N. Wijayati1, Supartono1 and E. Kusumastuti1
1Department of Chemsitry, Universitas Negeri Semarang, Indonesia
Email: nanikanang@gmail.com
Abstract. Turpentine is one of the oils obtained from pine trees with >80% α-pinene
composition. Turpentine oil has a high selling value by making α-pinene derivative through an
esterification reaction. The esterification reaction was carried out with time variation and
reaction temperature using natural zeolite. Characterization of the catalyst using X-Ray
Diffraction, IR spectroscopy and Scanning Electron Microscopy. The esterification reaction
product was analyzed by IR spectroscopy, and Gas Chromatography - Mass Spectroscopy. The
main product of α-pinene esterification reaction was α-terpinyl acetate (21.40%), and the
selectivity of 28.87 %, produced at 40ºC for 3 hours.
1. Introduction
Most of the pine trees in Indonesia is the kind of Pinus which produces turpentine with a composition
of 82% α-pinene and other components.Attempts to get oil terpertin added value is through a
distillation process that produces components of turpentine oil.One effort that turpentine oil has a high
sales value is by conducting an esterification reaction α-pinene to produce α-terpenil acetate which is
used widely in the perfume industry, especially on the soap.However, the presence of the wild-bit
terpenil acetate and the need is less economical so as to get it done by isolating it from the plant [1-3].
Natural zeolites are zeolites are widely available on the volcano and mined directly from nature that
cost far less than the zeolite synthesis.The main content of natural zeolite mineral morderit, the ratio
Si / Al is high so it has high thermal stability [4].
Esterification reaction between α-terpineol and acetic anhydride with a yield of 5.57% and a purity of
67.50% at room temperature.Gainsford et al [1] carry out the conversion of α-pinene into α-terpenil
acetate with H-beta zeolite at room temperature in 24 hours resulted in a 29% yield.Liu et al [2]
conducted an esterification reaction α-pinene into α-terpenil acetate selectivity α-terpenil highest
acetate 27.8% using acidic ionic liquid catalyst is [HSO3-(CH2)3 -Net 3] H2PO4.Li et al [3] conducted a
synthesis terpenil acetate using an ionic liquid as a catalyst octadecyl amine ethoxylates, optimum
condition is achieved at a ratio of n (α-pinene): n (ionic liquids): n (acetic acid) = 5: 0.3: 20 , where n
-pinene) = 0.05 mol, carried out at a temperature of 30 ° C with a reaction time of 10 hours to
obtainterpenil acetate yield of 35.70%.
This work to study to change the oil component of turpentine in the form of a compound α-pinene to
terpenil acetate by the esterification reaction using natural zeolite catalyst.
2. Method
The tools used in the study is a fractional distillation under reduced pressure, IR spectrophotometer,
X-ray diffraction, Scanning Electron Microscopy (SEM), and Gas Chromatography-Mass
Spectrometer. The material used is turpentine oil, distilled water, natural zeolite, ammonia, pyridine,
Na2SO4, acetic anhydride, filter paper, dichloromethane, saturated sodium bicarbonate.
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
Esterification of α-pinene,
α-Pinene 0.5g were mixed in 10 mL of acetic anhydride, 10 mL H2O, 10 mL of dichloromethane and
then stirred using a mechanical stirrer for 3 hours at a temperature of 40°C with 0.5 g of activated
natural zeolite in a closed flask equipped with a thermometer. The reaction products were tested with
the GC, FTIR, GC-MS.
3. Result and Discussion
3.1. Characterization of natural zeolite
Natural zeolites are shaped chunks of crushed then pulverized and sieved with a 100 mesh sieve in
order to be the same size and the natural zeolite surface area becomes larger. Activation of natural
zeolite with acid and salt treatment aims to improve the performance of natural zeolite. Natural
zeolites are already activated with HF 1% and then soaking with 6M HCl solution aimed dealuminated
natural zeolite can improve the ratio of Si/Al.
The results of the analysis of activated natural zeolite with XRD in Figure 1 shows that there are three
highest peaks in the H/ZA is at = 27,21º; 21,34º and 25,09º. The specific peaks is the peak of
morderitie at 2θ = 20,9º; 25,63º; 26º; 26,25º; 27,67º. While the typical peak for morderit located on the
highest peak at 2θ = 25,631º and 27,651º (JCPDS No. 700232). Suitability pattern difraktogram H/ZA
with morderit can be concluded that the samples H/ZA has type structure mordernit
Figure 1.Diffractograms of catalyst H/ZA
Determination of the number of catalyst acid sites H/ZA with ammonia of 0.81 mol / g, whereas with
pyridine of 0.79 mol/g. The total number of acid sites with ammonia on the H/ZA catalyst is higher
than the number of acid sites with pyridine. This is because ammonia is a stronger base than pyridine.
In addition, the size of the ammonia molecule is relatively smaller than the pyridine adsorbed onto the
surface in the pores, while the pyridine is only adsorbed on the outer surface (pore mouth).
The results of the scanning using SEM in Figure 2, obtained a morphological picture of H/ZA at
5000x magnification showed that the size of the distribution reached 20 micrometers scale. at 10,000x
magnification shows that the distribution size reaches 10 micrometers scale. The molecular size of
H/ZA is uneven and irregularly shaped.
3
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
(a)
(b)
3.2. The Esterification from turpentin oil
The main componen of turpentin oil are the monoterpene compounds. The monoterpenes are essential
ingredients in fine chemical industry and flavor and parfume industry. The most important constituents
of monoterpenes are α- and β-pinene (Figure 3).
α- pinene β-pinene
Figure 3. (1) α- and (2) β-pinene
The turpentine oil are mobile liquids, usually non-coloured or slighty colored. The boiling point of the
turpentine oil between 155-156oC, the specific gravity (20oC) varies between 0.854-0868 g/mL and
the refractive index (20oC) between 1.4656. The oils are not soluble in water, but soluble in ethers,
dichloromethane and in other oils. Highly pure α- and (2) β-pinene can be obtained by fractional
distilation of turpentine oil. The main component of turpentine oil are a-pinene. Indonesia turpentine
oil contains about 57-86% α- pinene, 8-12% β-pinene and other groups monoterpenes with a number
of minor (Figure 4). The main products obtained from turpenine oil are camphene, limonene,
terpinene, terpinolene, α-terpineol, and terpinyl acetate, etc. [5].
The results of the identification of physical compound α-pinene which is a liquid, colored clear and
distinctive smell like turpentine. Based on the analysis using FTIR, α-pinene, group C = C at wave
number 1650 cm-1 showed that α-pinene including alkenes [6-7]. From gas chromatographic yield of
α-pinene turpentine oil isolated by 98.10%. The content of turpentine oil is the largest in the
compound α-pinene about 82%.
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
Figure 4. Chromatogram of turpentine oil
Alpha pinene esterification reaction takes place in situ in a reaction that occurs through hydration
reactions prior to the addition of distilled water to form α-terpineol then α-terpineol formed will
undergo an esterification reaction with acetic anhydride to form α-terpenil acetate. In this case allow
for other products in the esterification reaction α-pinene as fencyl acetate, bornil acetate, fencyl
alcohol, α-terpineol and borneol.
The α-pinene esterification reaction with variation of reaction time of 2, 3 and 4 hours yields terpinyl
acetate with yields of 16.04, 21.40, and 28.77% with the conversion of 51.57, 74.13 and 94.68%.
Table 1. Results of α-pinene esterification reaction time variations
Time
(h)
C (%)
Yield (%)
Selectivity
α-terpinyl
acetate
Fencyl
alcohol
Borneol
α-terpineol
Fencyl
acetate
Bornil
acetate
α-terpinyl
acetate
2
3
4
51.57
74.13
94.68
1.06
1.67
3.16
1.44
0.44
1.49
26.45
43.31
55.32
2.42
3.76
3.62
1.02
16.04
21.40
28.77
31,10
28,87
30,38
Reaction conditions: 0.5 g of pinene, 10 mL of acetic anhydride, 5 mL H2O, 10 mL dichloromethane, T = 40ºC
The α-pinene esterification with temperature variations of 30, 40 and 60 ° C with reaction time of 3
hours and the ratio of pinene acetic anhydride compound (1:15) yielded α-terpenyl acetate with 0.18,
21.40, and 14.72% with the conversion of 4.99, 74.13 and 52.44.
The effect of reaction temperature on α-pinene esterification is shown in Table 2. When the
temperature was low, the yield of α-terpinyl acetate was low. As the temperature was increased, the
yield of α-terpinyl acetate increased accordingly. When the temperature was high, the yield of
α-terpinyl acetate tended to decreased. The results showed the yield of α-terpinyl acetat first increased
and then decreased with increasing temperature [3].
Table 2. The effect of reaction temperature on α-pinene esterification reaction
Temp
C)
C (%)
Yield (%)
Selectivity
α-terpinyl
acetate
Fencyl
alcohol
Borneol
α-terpineol
Fencyl
acetate
Bornil
acetate
α-terpinyl
acetate
30
40
60
4,99
74,13
52,44
0,15
1,67
0,35
0,14
0,44
23,62
0,74
43,31
1,21
0,33
3,76
1,65
0,94
1,02
1,65
0,18
21,40
14,72
3,68
28,87
28,08
Reaction conditions: 0.5 g of pinene, 10 mL of acetic anhydride, 5 mL H2O, 10 mL dichloromethane,
t =3 hours
5
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
The results of the analysis of esterification of α-pinene using FTIR in Figure 5 that the aliphatic CH
absorptions at wave number 2923 cm-1, group C = C at wave number 1617 cm-1, group C = O at wave
numbers between 1735-1750 cm-1 and the peak of the C-O group at wave numbers between 1050 to
1300 cm-1 can be concluded that the compounds produced an ester compound. α-pinene that no group
C-O and C = O indicates that the compounds produce ester esterification of alkenes.
Figure 5.The IR spectrum (a) compound α-pinene (b) the results of esterification results
of α-pinene esterification reaction time of 3 hours, a temperature of 40 ° C.
The α-pinene compound has a fairly stretchy structure and the presence of a double-bonded reactive
ring within the α-pinene structure makes it easy to participate in cycle-opening reactions and
molecular rearrangement reactions. The esterification reaction mechanism of the α-pinene compound
is shown in Figure 6.
Figure 6. The esterification reaction mechanism of the α-pinene compound
4. Conclution
The α-pinene esterification reactor using natural zeolite catalyst at 40°C for 3 hours with a reactant
mole ratio between α-pinene and acetic anhydride (1:15) yielded α-terpenyl acetate of 21.40% and
selectivity 28.87 %
5. Acknowledgement
The authors would like to thank Directorate General of Higher Education (DGHE), Department of
National Education Republic Indonesia for to support.
6. References
[1] Gainsford, G.J., C.F. Hosie, & R.J. Wetson. 2000. Conversion of α-pinene To Terpinyl Acetate
Over H-Beta Zeolites. Applied Catalysis A: General, 209: 269277.
6
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2018 5th International Conference on Coastal and Ocean Engineering (ICCOE 2018) IOP Publishing
IOP Conf. Series: Earth and Environmental Science 171 (2018) 012043 doi :10.1088/1755-1315/171/1/012043
[2] Liu, S., C. Xie, S. Yu, F. Liu, & K. Ji. 2008. Esterification of α-Pinene and Acetic Acid Using
Acidic Ionic Liquids as Catalysts. Catalysis Communications, 9: 16341638.
[3] Li, L., S. Liu, Y Shi, S. Yu, C. Xie, & C. Qi. 2013. Synthesis of Terpinyl Acetate Using
OctadecylamineEthoxylate Ionic Liquids as Catalysts. Res ChemIntermed 39:20952105.
[4] Wijayati, N., T. Handayani, Supartono. 2017. Isomerization of α-pinene using
Zirconiua/Natural Zeolite Catalysts. Asian Journal of Chemistry. 29 (8) : 1705-1708.
[5] Wijayati, N., H.D. Pranowo, Jumina, &Triyono. 2013. The Acid Catalyzed Reaction of α-
PineneOver Y-Zeolit. Indo. J. Chem, 13(1): 59-65.
[6] AvilaM.C.,ComelliN.A.,CastellonE.R.,LopezA.J.,FloresR.C.,PonziE.N., PonziM.I., 2010.Study
of Solid Acid Catalysis For The Hydration of α-pinene. Journal of Molecular Catalysis, 322(1-
2): 106-112.
[7] Avila M.C., Ponzi M.I., danComelli N.A., 2015. Hydration of α-Pinene over Heteropoly Acid
H3PW12O40 and H3PMo12O40. Journal Chromatogr Sep Tech, 6(7) : 1-6.
... Wijayati et al. [7] were reported the esterification of α-pinene (isolated from turpentine oil) using natural zeolite (ZE) to result in 21.4% of yield with the selectivity of 28.87%. Further, terpinyl acetate yield has been enhanced (52.83%) with higher selectivity of 61.38% using H/ZY at 40 °C [8,9]. ...
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Jumina and Triyono 2013 The Acid Catalyzed Reaction of αPineneOver Y-Zeolit Indo
  • N Wijayati
  • H D Pranowo
Isomerization of α-pinene using
  • N Wijayati
  • T Handayani
  • Supartono
Wijayati, N., T. Handayani, Supartono. 2017. Isomerization of α-pinene using