Conversion Of Α-pinene Research Articles

Metabolic engineering of the borneol and camphor degradation pathways in Pseudomonas to produce optically pure bicyclic monoterpenes

Borneol, a medicinally important bicyclic monoterpene, facilitates drug transport across mucous membranes and the blood-brain barrier. Derivatives of borneol and camphor also have numerous biomedical applications. Borneol is currently industrially synthesized via the conversion of turpentine and α-pinene. However, the major product is racemic isoborneol rather than racemic borneol. Both borneol and isoborneol are degraded by the soil bacterium Pseudomonas via a well-established degradation pathway. Two indigenous Pseudomonas strains were used to convert racemic isoborneol to other optically pure bicyclic monoterpenes here. Our results showed that deletion of the camE2,5 gene alone from the strain TCU-HL1 genome led to the complete loss of borneol and camphor degradation ability. Knockout of both camE2,5 and bdh1 (TCU-HL1Δbdh1ΔcamE2,5) restored the degradation capability as the role of Bdh1 was replaced by that of Bdh2. This mutant converted racemic isoborneol into an optically pure bicyclic monoterpene, 2,5-diketocamphane, with a 45% recovery yield. RT-qPCR results suggested that camE2,5 expression plays a pivotal role in regulating the borneol/camphor degradation cluster. While (+)-borneol, (–)-borneol and (+)-camphor can be obtained from plants for mass production purposes, (–)-camphor cannot be obtained in the same manner. P. monteilii TCU-CK1 converted racemic isoborneol into (–)-camphor and 3,6-diketocamphane, with 15% and 10% recovery yields, respectively. In conclusion, we report the role of camE2,5 in regulating the borneol/camphor degradation operon and biotransformation methods to produce several optically pure bicyclic monoterpenes.

Low-cost and green straw derived hierarchical porous carbon as support to phosphotungstic acid for efficient and clean production of α-terpineol

This study developed a novel reciprocal template method to prepare MgO@Carbon micrometre tubes directly from straw-based biomass. Biomass carbon with a rich hierarchical porous structure (MRSC30) was obtained by acid-washing the MgO@Carbon micrometre tubes. The pore formation mechanism of MRSC30 was systematically analyzed using Density Functional Theory calculations and various characterization methods. The in situ growth of Mg(OH)Cl/MgO inside the biomass promotes the polymerized carbon precursors to be tightly affixed to the templating agent and provides exfoliation, support, and catalysis (i.e., electrostatic attraction, nucleophilic substitution, and electrophilic addition), which effectively promotes the formation of hierarchical porous carbon. The continuous release of light gases from the inside out during the prolongation of the decomposition temperature of the biomass by Mg(OH)Cl or/and MgO helps to promote the formation of stomata in the biomass carbon. The results showed that the method minimized the consumption of chemicals, energy consumption, and the time required to prepare HPC by 35.75%, 67.57%, and 52.38%, respectively. The phosphotungstic acid-loaded MRSC30 was successfully prepared as a highly amphiphilic and highly acidic solid acid catalyst and applied to the hydration of α-pinene to prepare superior performance gasoline additives (α-terpineol). Under optimal process conditions obtained in a batch reactor, the catalytic performance of the catalyst could be further improved by alternating flow using a novel semi-batch unsteady-state reactor developed in this institute, and the α-pinene conversion and the α-terpineol selectivity reached a maximum of 95.53% and 65.75%, respectively. At the same time, the reactor was able to substantially reduce the time required for hydration and the amount of moderately toxic acetone used compared to the conventional batch reactor by 20.83% and 62.50%, respectively.

Synthesis of terpinyl acetate from α-pinene catalyzed by α-hydroxycarboxylic acid-boric acid composite catalyst.

To enhance the yield of the one-step synthesis of terpinyl acetate from α-pinene and acetic acid, this study evaluated α-hydroxycarboxylic acid (HCA)-boric acid composite catalysts based on orthogonal experimental design. The most important factor affecting the terpinyl acetate content in the product was the HCA content. The catalytic performance of the composite catalyst was related to the pKa1 of HCA. The tartaric acid-boric acid composite catalyst showed the highest catalytic activity. The α-pinene conversion reached 91.8%, and the terpinyl acetate selectivity reached 45.6%. When boric acid was replaced with B2O3, the HCA composite catalyst activity was enhanced, which reduced the use of HCA. When the lactic acid and B2O3 content accounted for 10% and 4% of the α-pinene mass content, respectively, the α-pinene conversion reached 93.2%, and the terpinyl acetate selectivity reached up to 47.1%. In addition, the presence of water was unfavorable to HCA-boric acid composite catalyst. However, a water content less than 1% of the α-pinene mass content improved the catalytic activity of HCA-B2O3. When the tartaric acid-B2O3 was used as catalyst, and the water content was 1% of the α-pinene mass content, the α-pinene conversion was 89.6%, and the terpinyl acetate selectivity was 47.5%.

Biochar-based catalysts: a potential disposal of plant biomass from phytoremediation

Abstract In this study, the plant biomass from the phytoremediation was recovered, prepared, and investigated catalytic ability for the α-pinene isomerization. The results show that the Fe_loaded AAL biochar can catalyze the isomerization of a-pinene, with the α-pinene conversion of 90.5 % and the selectivities for monocyclic terpenes (limonene, terpinolene and γ-terpinene) of 57.1 %, bicyclic terpene (camphene) of 24.6 %. Iron in the plant biomass from phytoremediation is considered a decisive factor that heightened the conversion of α-pinene and the yield of isomers. This research has initially opened up a new application for the plant biomass absorbing heavy metal from the phytoremediation stage to resolve contaminants efficiently.

Ultrafast and continuous synthesis of an aluminophosphate type zeolite in microchannel and the hydrogenation of α-pinene

A highly efficient method was proposed for fast and continuous synthesis of LTA-type aluminophosphate (AlPO4-LTA) molecular sieves. The precursor was first synthesized in batch methods, then the precursor and tetramethyllamine hydroxide were coordinated to direct the synthesis of molecular sieves in a reaction system containing a poly (tetrafluoroethylene) (PTFE) microchannel reactor, which reduced the energy costs associated with mixing and cooling of reactant solutions. The reaction conditions, including molar ratio of reagents, temperature and flow rate, have also been rapidly optimized. The AlPO4-LTA have high crystallinity, high thermal stability, granule size (ca. 150 nm) and large surface area (679 m2/g). In addition, the hydrogenation of α-pinene catalyzed by Ni/AlPO4 nanocomposites was achieved with α-pinene conversion rate of 95.1% and cis-pinane selectivity of 95.9%, the catalyst had high activity during five cycles.

New core-shell catalyst for catalyzing hydrogenation of α-pinene to cis-pinane

Improving the selectivity of catalytic hydrogenation by designing new catalysts is an effective strategy for preparing cis-pinane. However, the stability of the reported catalyst is generally poor, and one of the main reasons is that metal active site is easy to drop. To address the issues, a new type of core–shell catalyst SiO2@Pd-Ni@mSiO2 is designed. The active metals can sandwich between the core and the shell, effectively preventing the dropping to enhance the related stability. The SiO2@Pd-Ni@mSiO2 shows outstanding stereoselectivity for the desired product, owing to its adsorption characteristics of shell pores, which can effectively promote α-pinene molecules directional adsorption, consequently enhancing the directional selective hydrogenation reaction of α-pinene with active metals and active hydrogen occurs in the interlayer. The conversion of α-pinene and the selectivity for cis-pinane are 99.4% and 93.3% under mild reaction conditions, respectively. Meanwhile, the catalyst SiO2@Pd-Ni@mSiO2 also has outstanding reusability. The preparation strategy of the new catalyst provides a new path for preparing efficient and stable catalysts for the hydrogenation of α-pinene.

The Application of Clinoptilolite as the Green Catalyst in the Solvent-Free Oxidation of α-Pinene with Oxygen

In this work, we present the catalytic application of the naturally occurring zeolite, clinoptilolite, in the oxidation of α-pinene, a natural terpene compound. Clinoptilolites with different average particle sizes, designated as (in μm) clin_1 (20), clin_2 (50), clin_3 (200), and clin_4 (500–1000), were used as the green catalysts in the solvent-free oxidation of α-pinene with oxygen. Prior to their application in catalytic tests, the catalysts were characterized by the following methods: nitrogen sorption at 77 K, EDXRF, XRD, SEM, UV-Vis, and FTIR. The effects of the temperature, amount of the catalyst, and reaction time on the product’s selectivity and α-pinene conversion were determined. At the optimal conditions (a temperature of 100 °C, catalyst content (clin_4) in the reaction mixture of 0.05 wt%, and 210 min reaction time), the following compounds were obtained as the main products: α-pinene oxide (selectivity 29 mol%), verbenol (selectivity 17 mol%), and verbenone (selectivity 13 mol%). The conversion of α-pinene under these conditions amounted to 35 mol%. Additionally, the kinetic modeling of α-pinene oxidation over the most active catalyst (clin_4) was performed. The proposed method of oxidation is environmentally safe because it does not require the separation of products from the solvent. In addition, this method allows for managing the biomass in the form of turpentine, which is the main source of α-pinene. The catalytic application of clinoptilolite in the oxidation of α-pinene has not yet been reported in the literature.

One-pot conversion of α-pinene into biomass high energy density fuel over a bifunctional zeolite catalyst

A shape-selective bifunctional catalyst (Rux/SOT-Hβ) was furnished by loading Ru onto the Hβ zeolite prepared via seed organic template (SOT) method using the seeds obtained via steam-assisted conversion (SAC) method. The Rux/SOT-Hβ catalyst exhibited both favorable acid-catalytic performance and hydrogenation performance in the two-stage one-pot conversion of α-pinene, enabling an energy-efficient process for producing biomass blended high energy density fuels (HEDF). The effect of preparation conditions of Hβ zeolite carrier, metal type, loading amount, and loading method on the catalytic performance of the bifunctional catalyst was investigated. After the optimization of the catalytic process over Ru1.2/SOT-Hβ using pinane as the reaction medium, the resulting liquid reaction mixture without undergoing further distillation and other operations was found to possess good biomass HEDF properties. Feasible recyclability of Ru1.2/SOT-Hβ catalyst in α-pinene one-pot conversion was also demonstrated by a 3-run recycling test.

Selective Catalytic Epoxidation-Hydration of α-Pinene with Hydrogen Peroxide to Sobrerol by Durable Ammonium Phosphotungstate Immobilized on Imidazolized Activated Carbon.

It is presented that the activated carbon was carboxylated with hydrogen peroxide and then acylated with 2-methylimidazole to prepare the porous carbon support with a surface imidazolated modification. Through the adsorption of phosphotungstic acid on the fundamental site of an imidazolyl group and then adjusting the acid strength with the ammonia molecule, a catalytic carbon material immobilized with ammonium phosphotungstate (AC-COIMO-NH4PW) was obtained, which was used to catalyze a one-pot reaction of convenient α-pinene and hydrogen peroxide to sobrerol. The bifunctional active site originated from the dual property of ammonium phosphotungstate, as the oxidant and acid presenting a cooperatively catalytic performance, which effectively catalyzes the tandem epoxidation-isomerization-hydration of α-pinene to sobrerol, in which the solvent effect of catalysis simultaneously exists. The sobrerol selectivity was significantly improved after the acid strength weakening by ammonia. Monomolecular chemical bonding and anchoring of ammonium phosphotungstate at the basic site prevented the loss of the active catalytic species, and the recovered catalyst showed excellent catalytic stability in reuse. Using acetonitrile as the solvent at 40 °C for 4 h, the conversion of α-pinene could reach 90.6%, and the selectivity of sobrerol was 40.5%. The results of five cycles show that the catalyst presents excellent stability due to the tight immobilization of ammonium phosphotungstate bonding on the imidazolized activated carbon, based on which a catalytic-cycle mechanism is proposed for the tandem reaction.

Study on the Hydration of α-Pinene Catalyzed by α-Hydroxycarboxylic Acid-Boric Acid Composite Catalysts.

In this study, seven types of α-hydroxycarboxylic acids were selected to form composite catalysts with boric acid, and their catalytic properties were studied using the catalytic hydration of α-pinene. The results showed that the composite catalyst of boric acid and tartaric acid had the highest catalytic activity. With an α-pinene, water, acetic acid, tartaric acid, and boric acid mass ratio of 10:10:25:0.5:0.4, the reaction temperature was 60 °C, the reaction time was 24 h, the conversion of α-pinene was 96.1%, and the selectivity of terpineol was 58.7%. The composite catalyst composed of boric acid and mandelic acid directly catalyzed the hydration of α-pinene in the absence of a solvent. Under the optimal conditions, the conversion of α-pinene reached 96.1%, and the selectivity of terpineol was 55.5%. When the composite catalyst catalyzed α-pinene to synthesize terpineol in one step, the terpineol was optically active, and terpineol synthesized using the two-step method with the dehydration of p-menthane-1,8-diol monohydrate was racemic. These composite catalysts may offer good application prospects in the synthesis of terpineol.

Studies on the catalytic activities of ZSM-5 zeolites with different aluminum contents in the green oxidation of α-pinene to high value-added products

α-Pinene is the terpene abundant in nature. It is present in the oils of coniferous trees, mainly pine. We demonstrate that from this renewable stock, high value-added products such as verbenone, verbenol, α-pinene oxide, can be obtained as the main products, and smaller quantities of pinanediol carvone myrtenol pinocarveol campholenic aldehyde, myrtenal, and carveol are also produced. All the products have numerous applications in medicine, cosmetics, and foods. Heterogeneous ZSM-5 zeolite catalysts with different aluminum contents – designated as (in wt% of Al) ZSM-5_1 (2.5), ZSM-5_2 (0.59), and ZSM-5_3 (0.38) – were applied in the green α-pinene oxidation with oxygen and without solvent. To date, the use of the ZSM-5 catalyst in the α-pinene oxidation process has not been described. The catalysts were characterized by UV-Vis, FTIR, EDXRF, XRD, SEM, DTA techniques, and by the nitrogen sorption method at 77 K. The effects of catalyst amount and properties, temperature and reaction time, on product selectivity and α-pinene conversion, were determined.

Ti3C2 MXenes-based catalysts for the process of α-pinene isomerization.

In this study, the catalytic performance of Ti3C2 MXene materials in the reaction of α-pinene isomerization was demonstrated. The influence of etching agents (HF, HF/H2SO4, and HF/HCl; weight ratios of mixed acids: 1 : 3, 1 : 4, and 1 : 5) on removing Al atoms from MAX phase, creation of an accordion-like structure typical for MXenes and catalytic activity of the produced samples have been revealed. The MXene HF obtained by MAX phase HF treatment exhibited the highest activity (conversion of α-pinene 74.65 mol%), while materials produced with the mixed acids (HF/H2SO4 and HF/HCl) showed a significant reduction in the conversion of α-pinene (on average about 28-fold). However, these last samples displayed an increase of about 10 mol% in the selectivity to the most desirable product-camphene. The high activity of MXene HF is a result of a high concentration of acid sites (11.62 mmol g-1) - the concentration of acid sites in the samples obtained by MAX phase mixed acids treatment was about 2.5-5.5 times smaller. This work proposes possible mechanisms for the α-pinene isomerization reaction on the MXene HF and on the MXene HF/H2SO4X : Y and MXene HF/HCl X : Y in connection with their structure.

Effective synthesis of limonene over mild alkali-modified 13X catalysts in α-pinene isomerization

The mild alkali-treated 13X was employed in the liquid phase isomerization reaction of α-pinene to increase the yield of limonene. A maximum α-pinene conversion of 100% and limonene yield of 59.1% could be achieved. Crystallinity could be well retained, and the amounts of medium-strong acid sites and the distribution of Brønsted and Lewis acid sites could be changed after the mild alkali treatment for 13X zeolite. Samples with higher micropore specific surface area were easier to obtain higher yields of limonene due to shape-selectivity. A proper amount of the medium-strong acid and the synergistic effect of Brønsted and Lewis acid sites were beneficial to enhance the catalytic activity and the yield of monocyclic product limonene. The main reason for catalyst deactivation could be the decrease in the active sites due to soft coke deposition. For the regeneration process, the conversions of α-pinene were between 95% and 99% during the first seven cycles and the conversion dropped to 90.6% after the eighth cycle, which demonstrated that the ethanol flushing and calcination could be an effective regeneration method for the 13X catalyst used in the α-pinene isomerization reaction.

CuAPO-5 as a Multiphase Catalyst for Synthesis of Verbenone from α-Pinene.

Copper(II)-containing aluminum phosphate material (CuAPO-5) was synthesized hydrothermally and used as a multiphase catalyst for the oxidation of α-pinene to verbenone. The catalysts were analyzed using X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area techniques, X-ray photoelectron spectroscopy (XPS), and ammonia temperature programmed reduction (NH3-TPD). Scanning electron microscopy (SEM), X-ray energy spectrometry (EDS), inductively coupled plasma emission spectroscopy (ICP-OES), Fourier infrared spectroscopy (FT-IR), and ultraviolet-visible spectroscopy (UV-vis) were performed to characterize the material. The effects of reaction temperature, reaction time, n(α-pinene)/n(TBHP), and solvent on the catalytic performance of CuAPO-5 were investigated. The results show that all the prepared catalysts have AFI topology and a large specific surface area. Copper is evenly distributed in the skeleton in a bivalent form. The introduction of copper increases the acid content of the catalyst. Under the optimized reaction conditions, 96.8% conversion of α-pinene and 46.4% selectivity to verbenone were achieved by CuAPO-5(0.06) molecular sieve within a reaction time of 12 h. CuAPO-5(0.06) can be recycled for five cycles without losing the conversion of α-pinene and the selectivity to verbenone.

Carbon catalysts from pine cones – Synthesis and testing of their activities

The work presents research on the synthesis of carbon catalysts from pine cones and their application in the oxidation of α-pinene. The preparation of carbon catalysts involved chemical activation with an aqueous potassium hydroxide solution and carbonization of the obtained precursor. The pine cones carbonization was performed for 1 h at the temperatures range from 700° to 1000°C in an inert gas atmosphere (N2). Characterizations of the activated carbons were performed with the following instrumental analyses: XRD, SEM, and XPS. No solvent was used in the oxidation studies, and molecular oxygen was the oxidizing agent. The effects of three parameters – temperature, amount of the carbon catalyst, and reaction time – on the values of conversion of α-pinene, as well as the product selectivities, were investigated. It was shown that it is most advantageous to perform the oxidation of α-pinene at 100 °C for 1 h with the PC_850 catalyst (so-named for the temperature of its carbonization process, 850 °C), whose content in the reaction mixture is 0.5 wt%. Under these conditions, the conversion of α-pinene amounted to 41 mol%. Moreover, the selectivities of the three main products were: α-pinene oxide (28 mol%), verbenol (16 mol%), and verbenone (13 mol%). In addition to these products, other valuable compounds, such as campholenic aldehyde, pinocarveol, myrtenal, myrtenol, carveol, carvone, and pinanediol were also produced.

Construction of heterojunctions CeO2 interfaced Nb, Sn, Ti, Mo and Zn metal oxide catalysts for photocatalytic oxidation of α-pinene inert C-H

• Heterojunctions CeO 2 -M (M = Zn, Ti, Sn, Mo, Nb) metal oxides catalysts are synthesized by sol–gel method. • CeO 2 -M catalysts show varying photoactivity for oxidation of α-pinene to aroma oxygenates. • CeO 2 -Mo shows the best photocatalytic performance for α-pinene conversion and selectivity to pinene oxide. • The contribution from interfaced redox, oxygen vacancies, and efficient separation of e - /h + are accountable for the enhanced photoactivity of CeO 2 -M catalysts than CeO 2 . • Pinene oxide is obtained with up to 64% selectivity at 66% α-pinene conversion within 5 h of reaction irradiation time. Construction of heterojunctions semiconductors provide an improvement in photo-optics for light absorption, photo carriers generation, and transfer for their efficient utilization in redox reactions. Herein, heterostructured CeO 2 catalysts containing Ti, Mo, Nb, Sn and Zn oxides nanostructures are synthesized and evaluated for their photoactivity in α-pinene selective oxidation using acetonitrile solvent at 25 °C reaction temperature. Both conversion and selectivity are affected by the nature of the hetero-interfaced metal oxide to CeO 2 . CeO 2 -Mo shows the best photocatalytic performance to achieve pinene oxide selectivity of 64% at 66% of pinene conversion after 5 h of light irradiation. The enhanced photoactivity of CeO 2 heterostructured catalysts compared to CeO 2 is ascribed to their red-shift light absorption edges to visible region because of the two metal oxides interactions and structure modifications, which improved the e - /h + charge carrier’s generation and separation for their efficient transfer due to suppressed recombination. Importantly, the combination of redox nature of interfaced CeO 2 heterostructured catalysts and oxygen vacancies shows to be pivotal for the photocatalytic activity enhancement in the selective oxidation of pinene inert C-H bond.

The Studies on α-Pinene Oxidation over the TS-1. The Influence of the Temperature, Reaction Time, Titanium and Catalyst Content

The work presents the results of studies on α-pinene oxidation over the TS-1 catalysts with different Ti content (in wt%): TS-1_1 (9.92), TS-1_2 (5.42), TS-1_3 (3.39) and TS-1_4 (3.08). No solvent was used in the oxidation studies, and molecular oxygen was used as the oxidizing agent. The effect of titanium content in the TS-1 catalyst, temperature, reaction time and amount of the catalyst in the reaction mixture on the conversion of α-pinene and the selectivities of appropriate products was investigated. It was found that it is most advantageous to carry out the process of α-pinene oxidation in the presence of the TS-1 catalyst with the titanium content of 5.42 wt% (TS-1_2), at the temperature of 85 °C, for 6 h and with the catalyst TS-1 content in the reaction mixture of 1 wt%. Under these conditions the conversion of α-pinene amounted to 34 mol%, and the selectivities of main products of α-pinene oxidation process were: α-pinene oxide (29 mol%), verbenol (15 mol%) and verbenone (12 mol%). In smaller quantities also campholenic aldehyde, trans-pinocarveol, myrtenal, myrtenol, L-carveol, carvone and 1,2-pinanediol were also formed. These products are of great practical importance in food, cosmetics, perfumery and medicine industries. Kinetic studies were also performed for the studied process.

Sulfuric acid modified clinoptilolite as a solid green catalyst for solvent-free α-pinene isomerization process

The isomerization of α-pinene – a renewable bioresource – was investigated as a relatively simple method for the syntheses of camphene and limonene, industrially important products. The catalytic activity of H 2 SO 4 -modified clinoptilolite was evaluated without any solvent and the results show its applicability as a novel, green, reusable and promising catalyst in organic syntheses. The method is cost-effective and energy efficient because of the use of relatively low temperatures: at 30 °C and after 1 h, conversion was equal to 18%. In addition, this process has a short-time performance: 100% conversion after only 4 min at 70 °C. Camphene and limonene were the products that were formed with the highest selectivities of 50% and 30%, respectively. Clinoptilolite modified by H 2 SO 4 solutions (0.01–2 M) as a catalyst for α-pinene isomerization has not been described up to now. The catalyst samples were characterized using various instrumental methods (XRD, FT-IR, UV–Vis, SEM, and XRF). The nitrogen sorption method was used to determine the textural parameters, and the acid-sites concentration was established with the help of the titration method. The mixtures of compounds were analyzed via gas chromatography (GC). The comprehensive kinetic modeling of α-pinene isomerization over the most active catalyst (clinoptilolite modified by 0.1 M H 2 SO 4 solution) was performed. The first order kinetics of α-pinene conversion was found, and the value of the reaction rate constant at 70 °C was equal to 8.19 h −1 . It was concluded that the high activity of the prepared modified clinoptilolite in α-pinene isomerization is a multifaceted function of textural properties, crystallinity, chemical composition, and acid-sites concentration. • New concept of sustainable and ecological technology of organic syntheses • H 2 SO 4 -modified clinoptilolite is an efficient catalyst for α-pinene isomerization • Cost-effective and energy-efficient process even at low temperatures • Very fast α-pinene isomerization: 100% conversion after 4 min at 70 °C • Camphene and limonene are main products with 50% and 30% respective selectivities

Microwave irradiation assisted methoxylation of α-pinene using potassium alum [KAl(SO4)2] catalyst

Methoxylation is a reaction to produce of ether compounds using methoxy ions. The α-pinene methoxylation using potassium alum catalyst was carried out using a microwave with power variations of 320, 480 and 640 W, mass of the catalyst 0.3; 0.6 and 0; 9 g, and mole ratio of reactants 1:15, 1:30 and 1:45 mole. Identification of the reaction results was performed using GC, GC-MS and FT-IR. The product obtained in α-pinene methoxylation is mirtenyl methyl ether (MME) and terpinyl methyl ether (TME). The conversion of α-pinene with the variation of 480 W microwave power, mass of catalyst 0.3 g and mole ratio of reactants 1:15 at 120 seconds was 99.82% with the selectivity of MME and TME were obtained 32.0 % and 1.4%, respectively.

Esterification of α-pinene using TCA/Zeolite Y catalyst

Indonesian turpentine oil contains α-pinene (70-90%), β-pinene (5-10%), and 3-carene (4-10%). This study aims to determine the effect of temperature, time, and mass of the catalyst on the α-pinene esterification. The esterification was carried out at 25, 40 and 50°C for 1, 2, 3, and 4 hours with variations in the catalyst mass of 100, 300 and 500 mg. This reaction was carried out in a three neck round bottom flask equipped with a heater, thermometer and magnetic stirrer. The ester produced in the α-pinene transformation through the esterification is carvyl acetate. The optimum results were obtained at temperature of 40°C and the addition of catalyst of 500 mg with α-pinene conversion of 67.81% and selectivity of carvyl acetate at 81.92% for 1 h.