Catalyzed Biodiesel Production Research Articles

ChemInform Abstract: Carbohydrate‐Derived Solid Acid Catalysts for Biodiesel Production from Low‐Cost Feedstocks: A Review

AbstractReview: 91 refs.

Carbohydrate-derived Solid Acid Catalysts for Biodiesel Production from Low-Cost Feedstocks: A Review

Currently, most biodiesels are produced from virgin vegetable oils using a transesterification reaction. However, there are a number of other potential cheap sources for biodiesels, such as deep-frying oils/fats and palm fatty acid distillate (PFAD). PFAD is a lower-value by-product of the palm oil industry and is an economical source for biodiesel production. Due to the high cost of biodiesel production, the formulation of a new method to produce a cheaper biodiesel is imperative. Low-quality feedstocks (especially PFAD) using green and highly reusable catalysts have gained popularity due to their low production cost. High free fatty acids (HFFA) in the feedstock causes problems during the biodiesel production process, especially with the use of basic heterogeneous and homogenous catalysts. Recently, the effectiveness of a solid acid catalyst to catalyze biodiesel production from HFFA feedstock has caught the attention of researchers.This comprehensive article explores the use of low-quality feedstocks and carbon-based catalysts for the conversion of a waste refinery crude palm oil product which contains a high percentage of FFA. The production and characterization of carbohydrate-derived solid acid catalysts are discussed, including their physico-chemical property measurements. Techniques used for the synthesis of biodiesels are also included. In addition, transesterification process variables such as the oil/methanol molar ratio, catalyst concentration, reaction time, and temperature are investigated. The final part of the article contains the combustion, emissions, and performance of produced biodiesels. Finally, conclusions, including perspectives and future developments, are also presented. The aim of this article is to demonstrate the current state of the use of low-quality feedstocks and green heterogeneous solid acid catalysts for the use in biodiesel production.

Enzyme‐catalyzed transesterification of lipids in methyl acetate using a methanol tolerant lipase from Proteus mirabilis (583.5)

Recombinant lipase catalyzed biodiesel production has the potential to be more economically efficient than traditional acid and/or base catalyzed methods. Enzyme catalysis may require smaller loads, lower temperatures, less time and can be repeated if immobilized enzymes are utilized. However, many lipases expressed in E.coli are found in inclusion bodies, making recombinant production difficult. Further, often they are denatured in the methanol, the most common acyl acceptor. Lipase from Proteus mirabilis is naturally soluble in E.coli and has previously been mutated for methanol tolerance. These “dieselzymes” have not been previously characterized or optimized in reactions using alternate acyl acceptors. Mutated “dieselzymes” have been expressed in E.coli using the pET28 bacterial expression vector, purified using immobilized metal affinity chromatography and characterized for transesterification activity in reactions using methyl acetate, p‐nitrophenyl palmitate, and synthetic triacylglycerides at varying pHs and temperatures

Integrated lipase production and in situ biodiesel synthesis in a recombinant Pichia pastoris yeast: an efficient dual biocatalytic system composed of cell free enzymes and whole cell catalysts

BackgroundLipase-catalyzed biotransformation of acylglycerides or fatty acids into biodiesel via immobilized enzymes or whole cell catalysts has been considered as one of the most promising methods to produce renewable and environmentally friendly alternative liquid fuels, thus being extensively studied so far. In all previously pursued approaches, however, lipase enzymes are prepared in an independent process separated from enzymatic biodiesel production, which would unavoidably increase the cost and energy consumption during industrial manufacture of this cost-sensitive energy product. Therefore, there is an urgent need to develop novel cost-effective biocatalysts and biocatalytic processes with genuine industrial feasibility.ResultInspired by the consolidated bioprocessing of lignocellulose to generate bioethanol, an integrated process with coupled lipase production and in situ biodiesel synthesis in a recombinant P. pastoris yeast was developed in this study. The novel and efficient dual biocatalytic system based on Thermomyces lanuginosus lipase took advantage of both cell free enzymes and whole cell catalysts. The extracellular and intracellular lipases of growing yeast cells were simultaneously utilized to produce biodiesel from waste cooking oils in situ and in one pot. This integrated system effectively achieved 58% and 72% biodiesel yield via concurrent esterified-transesterified methanolysis and stepwise hydrolysis-esterification at 3:1 molar ratio between methanol and waste cooking oils, respectively. Further increasing the molar ratio of methanol to waste cooking oils to 6:1 led to an 87% biodiesel yield using the stepwise strategy. Both water tolerance and methanol tolerance of this novel system were found to be significantly improved compared to previous non-integrated biodiesel production processes using separately prepared immobilized enzymes or whole cell catalysts.ConclusionWe have proposed a new concept of integrated biodiesel production. This integrated system couples lipase production to lipase-catalyzed biodiesel synthesis in one pot. The proof-of-concept was established through construction of a recombinant P. pastoris yeast strain that was able to grow, overexpress T. lanuginosus lipase, and efficiently catalyze biodiesel production from fed waste cooking oils and methanol simultaneously. This simplified single-step process represents a significant advance toward achieving economical production of biodiesel at industrial scale via a ‘green’ biocatalytic route.

Synthesis and characterization of CuO/C catalyst for the esterification of free fatty acid in rubber seed oil

Plant oils or animal fats that contain high free fatty acid (FFA) are not preferred for base catalyzed biodiesel production. Pre-esterification is widely used to reduce the FFA content of the oil for avoiding saponification and associated purification cost. In the present study, carbon supported copper oxide (CuO/C) catalyst was prepared for the esterification of FFA in the rubber seed oil (RSO) which was extracted from the fresh seed by soxhlet extractor using hexane as a solvent. Copper nanoparticles were synthesized by sol–gel method and the nanoparticles were impregnated into the pore network of the carbon support. The copper impregnated activated carbon powder was calcined at 400°C in a furnace for 6h, leading to the formation of CuO/C. The catalyst was characterized by using Brunauer Emmett Teller, X-ray photoelectron spectroscopy, Energy-dispersive X-ray spectroscopy and Thermogravimetric analysis. Moreover, Hammett indicator method was used to determine the acidity of the catalyst. The effects of reaction temperature, methanol/FFA molar ratio, catalyst concentration on the FFA conversion were also studied. Based on the experimental results, methanol to FFA ratio of 10:1, catalyst dose 8wt%, reaction time of 6h and temperature 65°C were found as the optimum for the esterification reaction. Therefore, the developed catalyst could be effectively used for the esterification of FFA in plant oil.

Techno-Economic Analysis of an Alkali Catalyzed Biodiesel Production Using Waste Palm Oil

In this contribution, we present an in-depth analysis of an alkali catalyzed biodiesel production using waste palm oil. In view of the limited availability of non-renewable energy sources and the environmental concerns due to the high polluting nature of fossil fuels, biodiesel is seen as a future fuel alternative. We consider a waste palm oil with 6 % free fatty acids as a feedstock, which makes this process economically attractive. A complete process including esterification and transesterification is simulated using the Aspen Plus process simulator. The quality of a produced biodiesel is compared against different standards. In the subsequent part, the effect free fatty acid in feed oil on the overall biodiesel production is tested. In the last section of this paper, a techno-economic analysis and the scale-up study is carried out to determine the dependence of the feasibility of process on production capacity. The results show that higher capacity is desirable.

A novel and robust recombinant Pichia pastoris yeast whole cell biocatalyst with intracellular overexpression of a Thermomyces lanuginosus lipase: Preparation, characterization and application in biodiesel production

A novel and robust recombinant Pichia pastoris yeast whole cell catalyst (WCC) with functional intracellular expression of Thermomyces lanuginosus lipase (Tll) was constructed and characterized for biodiesel production from waste cooking oils. This permeabilized WCC was able to convert waste cooking oils to biodiesel with 82% yield within 84 h at 6% dosage whole cells. The WCC showed two fold catalytic activity of 0.73 U/mg DCW compared to its commercial counterpart Lipozyme TLIM (immobilized Tll). Short chain alcohol tolerance of this WCC was significantly improved compared to Lipozyme TLIM. This beneficial property enabled it to catalyze biodiesel production efficiently with one step addition of methanol. The reusability of this biocatalyst retained 78% activity after three batch cycles. This easily prepared and cost-effective WCC showed better catalytic performance than Lipozyme TLIM with respect to biodiesel yield and productivity, thus suggesting a promising cost-effective biocatalyst for biodiesel production.

A Review on Biodiesel Synthesis Using Catalyzed Transesterification Base Ionic Liquids as Catalyst

onic liquid is a green catalyzer and solvent which can be designed by changing the structure of its cation or anion. Ionic liquid has been used in diverse chemical reactions. Especially, Ionic liquids as environmentally friendly catalysts were applied in biodiesel production. Preparation of biodiesel catalyzed by ionic liquids have many merits, such as no corrosion to equipment, no pollution to environment, and reusability. In this paper, the advances in the base ionic liquids catalysts and their application in biodiesel production were reviewed. The characterization of the ionic liquids were summarized. In addition, the prospect for the application of the basic ionic liquids to catalyze biodiesel production was also stated. Since the cost of ionic liquid may be an issue, there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.

Progress in Research of Lewis Acid Ionic Liquids Used as Catalyst in Biodiesel Synthesis

onic liquid is a green catalyzer and solvent which can be designed by changing the structure of its cation or anion. Ionic liquid has been used in diverse chemical reactions. Especially, Ionic liquids as environmentally friendly catalysts were applied in biodiesel production. Preparation of biodiesel catalyzed by ionic liquids have many merits, such as no corrosion to equipment, no pollution to environment, and reusability. In this paper, the advances in the Lewis acid ionic liquids catalysts and their application in biodiesel production were reviewed. The characterization of the ionic liquids were summarized. The catalytic reaction mechanism of the Lewis acid ionic liquids in the biodiesel production was discussed. In addition, the prospect for the application of the Lewis acid ionic liquids to catalyze biodiesel production was also stated. Since the cost of ionic liquid may be an issue, there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.

A Review on Brønsted Acid Ionic Liquids Catalysts for Biodiesel Synthesis through Transesterification

Biodiesel has attracted considerable interest in recent years as an alternative, biodegradable and nonpolluting transportation fuel. Conventional alkaline process for biodiesel production are energy consuming and generate undesirable by-products such as soaps, that make difficult the separation and purification of biodiesel. Ionic liquids as environmentally benign chemical solvent, had been used in diverse chemical reactions. Especially, they could be applied in biodiesel production. Preparation of biodiesel catalyzed by ionic liquids have many merits, such as no corrosion to equipment, no pollution to environment, and reusability. Ionic liquids can improve the catalytic activity and they have wide utilization prospect in biodiesel preparation. In this paper, the advances in the Brønsted ionic liquids catalysts and their application in biodiesel production through transesterification of oils and fats were reviewed. In addition, the prospect for the application of the ionic liquids to catalyze biodiesel production was also stated. Since the cost of ionic liquid may be an issue, there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.

Progress in Research of Brønsted Acid Ionic Liquid Catalysts for Synthesis of Biodiesel through Esterification of Fatty Acids

Biodiesel has attracted considerable interest in recent years as an alternative, biodegradable and nonpolluting transportation fuel. Conventional alkaline process for biodiesel production are energy consuming and generate undesirable by-products such as soaps, that make difficult the separation and purification of biodiesel. Ionic liquids as environmentally benign chemical solvent, had been used in diverse chemical reactions. Especially, they could be applied in biodiesel production. Preparation of biodiesel catalyzed by ionic liquids have many merits, such as no corrosion to equipment, no pollution to environment, and reusability. Ionic liquids can improve the catalytic activity and they have wide utilization prospect in biodiesel preparation. In this paper, the advances in the Brønsted ionic liquids catalysts and their application in biodiesel production through esterification of fatty acids were reviewed. In addition, the prospect for the application of the ionic liquids to catalyze biodiesel production was also stated. Since the cost of ionic liquid may be an issue, there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.

A Two-step Catalytic Production of Biodiesel from Waste Cooking Oil

Waste cooking oil (WCO) was used as a potential feedstock for biodiesel production. High levels of free fatty acids (9.85% w/w) in WCO made it an undesirable substrate for direct transesterification reaction. To solve this issue, a two-step process was implemented in this research. Firstly, esterification reaction was performed in presence of sulfuric acid as a common acid catalyst to reduce the amount of FFA to less than 1.5% w/w. The triglycerides (TGs) in WCO were transesterified with methanol catalyzed by potassium hydroxide in the second step of reaction. Several effective parameters were evaluated in terms of reaction temperature (323-363 K), reaction time (0.5-3 h) and catalyst concentration (0-5.52% w/w). The optimum reaction conditions were defined as the reaction temperature of 355 K, reaction time of 3 h and catalyst concentration of 3.68~ 4% w/w, in which maximum FFA conversion of 87 wt% was obtained. The biodiesel synthesis condition in the second stage was defined as the reaction temperature of 338 K, methanol/ WCO molar ratio of 6:1, KOH concentration of 1% w/w and reaction time of 90 min; under these conditions, maximum triglyceride (TG) conversion of 96.66 wt% was obtained.

Optimization of novel pyrazolium ionic liquid catalysts for transesterification of bitter apple oil

In the present study, 4 different functionalized pyrazoliums based on sulfoalkyl-pyrazolium hydrogensulfate and alkylsulfo-alakylpyrazolium hydrogensulfate were explored to catalyze biodiesel production from bitter apple oil (BAO). The results demonstrated that a longer chains catalyst of 2-(4-sulfobutyl) pyrazolium hydrogensulfate (SBPHSO4) exhibited the highest catalytic activity, which is attributed to its strong acidity. The highest yield of esters was up to 89.5% when the reaction was carried out under the conditions of 5.2wt% of SBPHSO4, molar ratio of methanol to BAO of 15:1, 170°C, and 800rpm for 6h. These results demonstrated that ionic liquids offer a promising new type of pyrazolium catalyst for biodiesel production. The use of clean ionic liquids in preparing clean biodiesel could solve the drawbacks associated with using the old conventional catalysts and might be employed as an efficient catalyst for such relevance.

Production, characterization and applications of organic solvent tolerant lipase by Pseudomonas aeruginosa AAU2

Abstract Jatropha seedcake (JSC) represents an important environmental problem owing to its toxicity for the biodiesel producing sectors where they are generated in bulk as a major by-product. The aim of the present work was to study the feasibility of JSC as a substrate for lipase production under submerged condition. Pseudomonas aeruginosa AAU2 isolated from dumped rotting JSC was found to produce extracellular solvent tolerant lipase (0.432 U ml −1 ). A 11.4-fold increase in enzyme yield was obtained in an optimized medium containing 20 g JSC/l, 2.5 g potassium nitrate/l and 0.1 v/v% Tween 80 after 60 h of incubation at 30 °C under shake flask conditions (150 rpm). The pH and temperature optima of the partially purified AAU2 lipase were 7.5 and 40 °C, respectively. The AAU2 lipase was found to be a cysteine hydrolase and exhibited preference towards longer carbon chain fatty acid ester substrates over the shorter ones. The enzyme exhibited significant stability in the presence of commercial detergents namely, Ezee ® and Wheel ® . The AAU2 lipase efficiently catalyzed biodiesel production using Jatropha oil. In addition, the enzyme also hydrolyzed 86.49% of commercially available phorbol ester (phorbol 12-myristate 13-acetate) within 12 h of incubation at 37 °C, suggesting its application in detoxification of phorbol ester from JSC. These results demonstrate viable approach for utilization of JSC biomass and degradation of phorbol esters by P. aeruginosa AAU2.

Cloning, Expression and Characterization of a Lipase from <i>Bacillus Subtilis</i> Strain I<sub>4</sub> with Potential Application in Biodiesel Production

A lipase gene from sequencing genomic DNA of Bacillus subtilis strain I4 (I4-2) was cloned and expressed in E. coli. The deduced amino acid (aa) sequences for the lipase I4-2 was composed of 31-amino-acid signal sequence and a 181-amino-acid mature part, corresponding to a molecular mass (Mr) of 19.33 kDa. Based on the Mr and the protein sequence, the lipase I4-2 was belong to the lipase family1.4. The activity of the purified recombinant lipase I4-2 was apparently optimal at 45°C and pH 7.0. The enzyme was stable at 25°C, and more than 56% of the initial activity after incubation in buffer pH 7.0 for 120 min at 37°C. In addition, lipase I4-2 was mixed with methanol (50, v/v) for 30 min and residual activity was 45%. lipase I4-2 can catalyzed biodiesel production from soybean oil at methanol : soybean (molar ratio of methanol to oil = 3:1), 10% n-hexane, 3.5% water. The results of GC–MS analysis demonstrated that a 3-stepwise process resulted in a 98% conversion yield after 8 h of reaction at 37°C.

Optimization of two-step catalyzed biodiesel production from soybean waste cooking oil

An acid–base-catalyst-based two-step biodiesel production experiment from soybean waste cooking oil was carried out to identify which parameter is the most influential among the experimental parameters by using the Taguchi method. Heterogeneous catalysts were used to avoid a water-consuming homogeneous catalyst removal process. Ferric sulfate and calcium oxide were used as acid and base catalysts, respectively, for the heterogeneous reaction. Reaction time and methanol-to-triglyceride mole ratio were significant factors. The optimum parameters for step 1 (acid esterification) were 4 h of reaction time, 4 wt. % of ferric sulfate amount, a 16:1 methanol to triglyceride mole ratio, and 400 rpm of mixing speed, respectively. For the transesterification step, the most influential factor was reaction time, and CaO amount was significant as well. On the other hand, the mole ratio of methanol and oil was relatively less significant. Optimum parameters were 3 h of reaction time, 2 wt. % of CaO, and a 12:1 methanol to triglyceride mole ratio with mixing speed at 400 rpm in this experimental range. Under the optimum conditions, waste cooking oil with 5.27 mg KOH/g of acid value was converted into crude biodiesel by a two-step process with fatty acid methyl ester content reaching 89.8 % without any further post-purification.

In situ biodiesel production from wet Chlorella vulgaris under subcritical condition

The conventional base catalyzed biodiesel production process uses refined vegetable oil as feedstock oil and is not environmentally friendly. The supercritical methanol technology does not require the use of catalyst but it is energy intensive due to the high temperature and pressure required in the process. In this work, a process was developed for producing biodiesel directly from wet Chlorella vulgaris biomass (80% moisture content) using subcritical water as catalyst. Under the following conditions: The ratio of wet biomass to methanol is 1/4(g/mL), the reaction temperature is 175°C and after 4h, the reaction product contained 89.71% fatty acid methyl esters (FAMEs). The yield is 0.29g FAME per g dry biomass. This is considerably higher than the yield of 0.20g FAME per g dry biomass obtained when the neutral lipid of C. vulgaris biomass was extracted and converted into FAME.

Process design and evaluation of value-added chemicals production from biomass

Three different biodiesel production processes were simulated using the SuperPro Designer program. The process for producing biodiesel from soybean oil and methanol was designed using commercial chemical catalysts. This chemical process was compared with the biological process catalyzed by immobilized enzymes. In addition, a hybrid process consisting of catalytic biodiesel production and enzymatic glycerol carbonate production was designed and simulated for the conversion of waste glycerol to value-added chemical. Finally, the economics and productivity of these processes were evaluated to determine economic feasibility.

BiotecVisions 2012, August

BiotecVisions 2012, August

Catalytic performance of cross-linked enzyme aggregates of Penicillium expansum lipase and their use as catalyst for biodiesel production

Cross-linked enzyme aggregates (CLEAs) of lipase from Penicillium expansum (PEL) were prepared directly from fermentation broth, a more practical and economically viable procedure than the generally used methods that require purified or partially purified enzymes for CLEA preparation. A systematic study of the activity and stability of PEL-CLEAs was undertaken in aqueous solution, organic solvents, and ionic liquids (ILs). Immobilization of the enzyme resulted in a significantly enhanced stability in aqueous solution with regard to pH and temperature. PEL-CLEAs showed an improved activity in the IL [BMIm][PF6] relative to that observed in hexane, both keeping increased with temperature (up to 90°C in the IL and 60°C in hexane). The effect of water content and water activity in these two nonaqueous media showed similar patterns as for the uncrosslinked enzyme. The half life of the CLEAs was higher in hydrophobic organic solvents (hexane and chloroform) than in aqueous solution, and presented a sigmoid relationship with the logP of the organic solvent tested. PEL-CLEAs catalyzed biodiesel production from microalgal oil in the IL [BMIm][PF6] with a conversion of 85.7%, demonstrating that they can be taken as a promising catalyst for this application.