Croton Megalocarpus Oil Research Articles

Rheological and Physicochemical Analysis of Nonedible Oils Used for Biodiesel Production.

Rheological and physicochemical characteristics of edible oils used for biodiesel production are well established; nonetheless, the rheological and physicochemical characteristics of nonedible oils are yet to be established. The present study therefore focuses on rheological and physicochemical characterization of nonedible vegetable oils that can be used as biodiesel feedstock. The selected vegetable oils studied include cashew nut shell liquid (CNSL), castor oil (CO), Croton megalocarpus oil (CMO), Podocarpus usambarensis oil (PUO), and Thevetia peruviana oil (TPO). Physicochemical parameters analyzed were free fatty acids, acid value, saponification value, peroxide value, iodine value, specific gravity, and moisture content using methods by the Association of Official Analytical Chemists (AOAC). Rheological properties were analyzed using a VT-550 Thermo Haake Viscotester operated by the Rheowin 3 Job Manager software. The preset parameters in the Viscotester were shear rate and temperature. The shear rate increased uniformly from 5 to 100 s–1 at the temperature range of 30–60 °C. The experimental data were fitted into rheological models of Newton, Bingham, Ostwald–de Waele (power-law), and Herschel–Bulkley using Rheowin 3 Data Manager. The oil yield was 29–65%, highlighting the feedstock’s potential for commercial biodiesel production. At a constant temperature, all oil samples exhibited a Newtonian flow behavior. In contrast to edible oils, nonedible oils exhibited high shear stress, emphasizing the reconstruction of new appropriate designs of production systems. The rheological models appropriate to represent the flow behavior of the samples were the Newton and Ostwald–de Waele models, with a fit of R2 = 0.990–1.000.

Kinetics of Transesterification of Croton megalocarpus Oil Using Alkaline Earth Catalysts with Conventional and Microwave Heating

Transesterification kinetics of Croton megalocarpus oil to produce fatty acid methyl esters (FAME) was studied using homogeneous NaOH and heterogeneous alkaline earth Nano MgO, MgO, Nano CaO, CaO, Reoxidized CaO, SrO, and BaO catalysts. Characteristic surface, bulk, and chemical properties of the heterogeneous catalysts were obtained which included surface area, pore properties, scanning electron micrography, X-ray diffraction, basic strength, and basicity. The catalyst porosity varied as Nano MgO > Nano CaO > MgO > CaO > CaO-RO > SrO > BaO and basicity as BaO > SrO > Nano CaO > CaO RO > CaO > Nano MgO > MgO. Catalysts NaOH, BaO, SrO, and Nano CaO gave a good FAME yield (>50%), and reaction order and rate constant have been reported for these catalysts, for both conventional heating and microwave irradiation. The overall reaction for NaOH was of 1st order for microwave irradiation with respect to triglyceride and of 2nd order with respect to triglyceride under conventional heating. For the heterogeneous catalysts, the overall reaction was of 3rd order, 2nd order with respect to triglyceride and 1st order with respect to methanol for both heating methods. Reaction rate constants for microwave irradiation were higher than those for conventional heating due to faster reaction rates under such heating. BaO was the most active heterogeneous catalyst, followed by SrO and Nano CaO, which was in accordance with their basicity.

Optimisation of transesterification of Croton megalocarpus oil over alkaline earth catalysts using conventional and microwave irradiation by response surface methodology

ABSTRACT Croton megalocarpus oil is a non-edible oil with potential to produce biodiesel in East Africa. Transesterification of the oil and methanol to produce fatty acid methyl ester (FAME) was studied using heterogeneous alkaline earth BaO, SrO, CaO, Nano CaO, Reoxidised CaO (CaO RO), MgO, Nano MgO, BeO catalysts; by conventional heating and by microwave irradiation. Catalysts were characterised by surface area, porosity, basic strength and basicity. FAME yield was obtained through Gas chromatography. Central Composite Design (CCD) was used to optimise process variables (reaction temp. /time, methanol-to-oil ratio, catalyst conc.) for the highest FAME yield through Response Surface Methodology (RSM) plots. Conventional heating gave a higher maximum yield, in the order: BaO(83%) > SrO(77%) > Nano CaO(74%) > CaO RO(42%) > CaO(32%) > Nano MgO(25%) > MgO(20%) > BeO(–). Yields were in order of the observed catalyst basicity, and independent of surface area. New catalyst CaO RO obtained from CaO showed higher activity. BeO showed no activity (<5%). Microwave irradiation gave slightly reduced maximum yields for BaO(78%), SrO(72%) and Nano CaO(62%). However, no such maxima were observed for other catalysts for the chosen reaction time. Microwave was found to be a superior heating mode due to highly reduced reaction times.

Transesterification of croton megalocarpus oil to biodiesel over WO3 supported on silica mesoporous-macroparticles catalyst

The transesterification of croton megalocarpus oil with methanol to fatty acid methyl ester (FAME) was carried out using WO3 supported on silica mesoporous-macroparticles (WO3/SMP) as a heterogeneous acid catalyst. The silica mesoporous-macroparticles (SMP) and WO3/SMP were synthesized by sol-gel and impregnation method, respectively. The catalysts were characterized with XRD, FTIR, N2 adsorption-desorption, SEM and TEM. The presence of WO3 gave a negative effect on the crystallinity and surface area of the SMP as evidenced by XRD and N2 adsorption-desorption studies, respectively. Pyridine adsorbed FTIR spectroscopy showed that the concentration of Brønsted and Lewis acid sites was dependent on the WO3 loading on SMP. 2wt% of WO3 loading on SMP (2WO3/SMP) exhibited the highest intensity of Lewis acid sites which is vital in transesterification reaction. Under the optimum reaction condition determined through response surface methodology (RSM), 2wt% WO3 loading, 4.5wt% catalyst amount, 9:1 methanol to oil molar ratio, 45min reaction time and 343K reaction temperature yielded a 96% of biodiesel product. The highest catalytic activity of 2WO3/SMP may be attributed to the high Lewis acid sites content and the presence of both intra- and interparticle pores of the catalyst that facilitated and enhanced the transport of reactants and products during the reaction.

Fuel Properties of Croton megalocarpus, Calophyllum inophyllum, and Cocos nucifera (coconut) Methyl Esters and their Performance in a Multicylinder Diesel Engine

AbstractBiodiesel has been considered recently as a viable alternative to fossil diesel fuels. This study aims to evaluate the potential of biodiesel production from Croton megalocarpus oil and compared it with coconut (Cocos nucifera) and Calophyllum inophyllum methyl esters. The study presents the physical and chemical properties of Croton megalocarpus, Calophyllum inophyllum and coconut methyl esters (CMME, CIME, and COME) together with their 10 and 20 % blends by volume (B10 and B20). This is followed by evaluating their blends in a multicylinder Mitsubishi Pajero diesel engine. It has been found that the properties of all biodiesel and their blends are comparable with ASTM D6751 and ASTM D7467 standards, respectively. Over the entire range of speed, it was found that the B10 and B20 blends of CMME, CIME, and COME result in average reduction in torque and brake power (BP) along with increased brake‐specific fuel consumption (BSFC) compared to pure diesel fuel. With respect to engine emissions, the fuel blends resulted in an average reduction in carbon monoxide (CO) and hydrocarbon (HC) emissions. However, the CMME and COME blends resulted in increased emissions of nitrogen oxides (NO) whereas CIME emits lower NO compared to pure diesel. It is concluded that B10 and B20 biodiesel blends can be used as diesel fuel substitutes without additional modifications.

Micro distributed energy system driven with preheated Croton megalocarpus oil – A performance and particulate emission study

As a carbon neutral biofuel, the cold pressed Croton megalocarpus oil (CMO) has the nature of easy production without any further chemical process, but suffers for its high viscosity and poor atomisation if being applied on the compression-ignition (CI) engine generator. A micro distributed energy system comprised of a modified 6.5kWe CI engine generator and an engine exhaust driven diffusion absorption refrigerator has been set up for domestic application, which applies both diesel and CMO. To minimise the negative impact of fuel properties of CMO, the temperature before injection has been elevated with the trace heater and the waste heat from the engine. The performance of the preheated CMO up to 90°C on the engine generator system reflects an improvement of the atomisation and combustion in the cylinder compared to the non-preheated CMO. The particulate emission test reveals the similarity of both the total number and the total weigh of the particulates emitted from the engine generator system running on diesel and CMO in 90°C.

Noncatalytic Biodiesel Fuel Production from Croton megalocarpus Oil

AbstractBiodiesel is currently considered as the most promising substitute for diesel fuel because of its similar properties to diesel. This study presents the use of the supercritical methanol method in the production of biodiesel from Croton megalocarpus oil. The reaction parameters such as methanol‐to‐oil ratio, reaction temperature and reaction time were varied to obtain the optimal reaction conditions by design of experiment, specifically, response surface methodology based on three‐variable central composite design with α = 2. It has been shown that it is possible to achieve methyl ester yields as high as 74.91 % with reaction conditions such as 50:1 methanol‐to‐oil molar ratio, 330 °C reaction temperature and a reaction period of 20 min. However, Croton‐based biodiesel did not sustain higher temperatures due to decomposition of polyunsaturated methyl linoleate, which is dominant in biodiesel. Lower yields were observed when higher temperatures were used during the optimization process. The supercritical methanol method showed competitive biodiesel yields when compared with catalytic methods.

Engine performance, exhaust emissions and combustion characteristics of a CI engine fuelled with croton megalocarpus methyl ester with antioxidant

The use of biodiesel as a substitute for petroleum-based diesel has become of great interest for the reasons of combating the destruction of the environment, the price of petroleum-based diesel and dependency on foreign energy sources. But for practical feasibility of biodiesel, antioxidants are added to increase the oxidation stability during long term storage. It is quite possible that these additives may affect the clean burning characteristics of biodiesel. This study investigated the experimental effects of antioxidants on the oxidation stability, engine performance, exhaust emissions and combustion characteristics of a four cylinder turbocharged direct injection (TDI) diesel engine fuelled with biodiesel from croton megalocarpus oil. The three synthetic antioxidants evaluated its effectiveness on oxidation stability of croton oil methyl ester (COME) were 1, 2, 3 tri-hydroxy benzene (Pyrogallol, PY), 3, 4, 5-tri hydroxy benzoic acid (Propyl Gallate, PG) and 2-tert butyl-4-methoxy phenol (Butylated Hydroxyanisole, BHA). The fuel sample tested in TDI diesel engine include pure croton biodiesel (B100), croton biodiesel dosed with 1000ppm of an effective antioxidant (B100+PY1000), B20 (20% croton biodiesel and 80% mineral diesel) and diesel fuel which was used as base fuel. The result showed that the effectiveness of the antioxidants was in the order of PY>PG>BHA. The brake specific fuel consumption (BSFC) of biodiesel fuel with antioxidants decreased more than that of biodiesel fuel without antioxidants, but both were higher than that of diesel. Antioxidants had few effects on the exhaust emissions of a diesel engine running on biodiesel. Combustion characteristics in diesel engine were not influenced by the addition of antioxidants in biodiesel fuel. This study recommends PY and PG to be used for safeguarding biodiesel fuel from the effects of autoxidation during storage. Overall, the biodiesel derived from croton megalocarpus oil can be utilized as partial substitute for mineral diesel.

Impact of antioxidant additives on the oxidation stability of biodiesel produced from Croton Megalocarpus oil

The increase in crude petroleum prices, limited resources of fossil fuels and environmental concerns have led to the search of alternative fuels, which promise a harmonious correlation with sustainable development, energy conservation, efficiency and environmental preservation. Biodiesel is well positioned to replace petroleum-based diesel. Biodiesel is a non-toxic, biodegradable and renewable biofuel. But the outstanding technical problem with biodiesel is that, it is more susceptible to oxidation owing to its exposure to oxygen present in the air and high temperature. This happens mainly due to the presence of varying numbers of double bonds in the free fatty acid molecules. This study evaluates oxidation stability of biodiesel produced from Croton megalocarpus oil. Thermal and Oxidation stability of Croton Oil Methyl Ester (COME) were determined by Rancimat and Thermogravimetry Analysis methods respectively. It was found that oxidation stability of COME did not meet the specifications of EN 14214 (6 h). This study also investigated the effectiveness of three antioxidants: 1,2,3 tri-hydroxy benzene (Pyrogallol, PY), 3,4,5-tri hydroxy benzoic acid (Propyl Gallate, PG) and 2-tert butyl-4-methoxy phenol (Butylated Hydroxyanisole, BHA) on oxidation stability of COME. The result showed that the effectiveness of these antioxidants was in the order of PY > PG > BHA.

Comprehensive Analysis of Fuel Properties of Biodiesel from Croton megalocarpus Oil

Of late, much emphasis has been placed on searching for alternative fuels and significant investigations have been carried out regarding the production of biodiesel, especially from non-edible vegetable oils, with a view to minimize the dependence upon liquid hydrocarbon fuels, reduce emissions, and boost the rural economy. In this paper, the properties of Croton megalocarpus oil methyl ester (COME) from C. megalocarpus seed oil (non-edible) were investigated to determine their suitability for use as a petrodiesel substitute. C. megalocarpus seed oil was found to contain free fatty acids (FFAs) of 1.73%, which was below the 2% recommended for the application of the one-step base-catalyzed transesterification method. The transesterification process was carried out at the following optimized conditions: methanol/oil molar ratio (mol/mol), 6:1; potassium hydroxide, 1.0 wt %; reaction temperature, 50 °C; agitation speed, 500 rpm; and reaction time, 60 min. COME obtained was analyzed by gas chromatography (GC) to determine the methyl ester yield. COME offered the maximum methyl ester yield of 89.6%. The fuel-related properties of COME, cold filter plugging point (CFPP), cloud point (CP), kinematic viscosity, lubricity, oxidative stability, cetane number, flash point, acid value, density, calorific value, and free and total glycerol, were determined and discussed in light of biodiesel standards, such as ASTM D6751 and EN 14214. The most remarkable feature of COME was the CFPP and CP, which were −11 and −6 °C, respectively. The good cold flow properties of COME demonstrate its operational viability during the cold season. Tribological results showed that the lubrication ability of COME was better than that of conventional diesel fuel. However, COME did not fulfill the oxidative stability requirements of ASTM D6751 and EN 14214.

Croton megalocarpus oil: A feasible non-edible oil source for biodiesel production

This study presents the feasibility of converting a non-edible oil source native to the Africa region – croton megalocarpus oil to methyl esters (biodiesel) using sulfated tin oxide enhanced with SiO 2 ( SO 4 2 - /SnO 2–SiO 2) as super acid solid catalyst. This study was conducted using design of experiment (DoE), specifically, response surface methodology based on three-variable central composite design (CCD) with alpha ( α) = 2. The reaction parameters studied are: reaction temperature (60–180 °C), reaction period (1–3 h) and methanol to oil ratio (1:6–1:24). Although the oil was found to contain high free fatty acid, however, yield up to 95% was obtained without any pre-treatment step with the following reaction conditions: 180 °C, 2 h and 15:1 methanol to oil molar ratio, while keeping constant catalyst concentration and stirring speed at 3 wt.% and 350–360 rpm, respectively.

Biodiesel production from Croton megalocarpus oil and its process optimization

Production of biodiesel from non-edible feedstocks is attracting more attention than in the past, for the purpose of manufacturing alternative fuels without interfering with the food chain. Biodiesel was produced using Croton megalocarpus oil as a non-edible feedstock. C. megalocarpus oil was obtained from north Tanzania. This study aimed at optimizing the biodiesel production process parameters experimentally. The parameters involved in the optimization process were the amount of the catalyst, of alcohol, temperature, agitation speed and reaction time. The optimum biodiesel conversion efficiency obtained was 88% at the optimal conditions of 1.0 wt.% amount of potassium hydroxide catalyst, 30 wt.% amount of methanol, 60 °C reaction temperature, 400 rpm agitation rate and 60 min reaction time. The properties of croton biodiesel which were determined fell within the recommended biodiesel standards. Croton oil was found with a free fatty acid content of 1.68% which is below the 2% recommended for the application of the one step alkaline transesterification method. The most remarkable feature of croton biodiesel is its cold flow properties. This biodiesel yielded a cloud and pour point of −4 °C and −9 °C, respectively, while its kinematic viscosity lay within the recommended standard value. This points to the viability of using croton biodiesel in cold regions.