A novel process for biodiesel production from sludge palm oil

Agro-Industrial Wastes as Potential Substrates for Rhamnolipid Production by Pseudomonas aeruginosa USM-AR2

Rhamnolipid has gained much attention in various fields owing to its distinctive functional properties compared to conventional chemical surfactants, which are mostly derived from petroleum feedstock. Production cost is one of the main challenges in rhamnolipid production, particularly when using refined substrates. One possible solution is to use agro-industrial wastes as substrates for rhamnolipid production. This is a promising strategy due to their abundance and commercially low value, while simultaneously alleviating an agro-industrial waste management problem in the environment. This study aims to evaluate agro-industrial wastes from local crops as possible low-cost alternative substrates for rhamnolipid production by a local isolate, Pseudomonas aeruginosa USM-AR2. Various liquid wastes, namely sugarcane molasses, rice washing water, overly mature coconut (OMC) water, empty fruit bunch (EFB) steam effluent, palm sludge oil (PSO) and palm oil mill effluent (POME) were screened as the main carbon source supplementing mineral salt medium (MSM) in the fermentation of P. aeruginosa USM-AR2. Batch fermentation was carried out in a shake flask system, agitated at 200 rpm and incubated at room temperature, 27 ± 2°C for 120 h. Among the substrates tested, PSO exhibited the highest biomass at 20.78 g/L and rhamnolipid production at 1.07 g/L. This study has shown the potential of agro-industrial wastes in Malaysia as an alternative resource for rhamnolipid production, transforming them into value added products, while reducing the amount of wastes discharged into the environment.

Continuous double-step acid catalyzed esterification production of sludge palm oil using 3D-printed rotational hydrodynamic cavitation reactor

Sludge palm oil (SPO) with high free fatty acid (FFA) content was processed using a continuous and double-step esterification production process in a rotor-stator-type hydrodynamic cavitation reactor. Three-dimensional printed rotor was made of plastic filament and acted as a major element in minimizing the FFA content in SPO. To evaluate the reduced level of FFAs using both methods, five independent factors were varied: methanol content, sulphuric acid content (H2SO4), hole diameter, hole depth, and rotor speed. The first-step conditions for the esterification process included 60.8 vol% methanol content, 7.2 vol% H2SO4 content, 5.0 mm diameter of the hole, 6.1 mm depth of the hole, and 3000 rpm speed of the rotor. The initial free fatty acid content decreased from 89.16 wt% to 35.00 wt% by the predictive model, while 36.69 wt% FFA level and 94.4 vol% washed first-esterified oil yield were obtained from an actual experiment. In the second-step, 1.0 wt% FFA was achieved under the following conditions: 44.5 vol% methanol content, 3.0 vol% H2SO4 content, 4.6 mm hole diameter, 5.8 mm hole depth, and 3000 rpm rotor speed. The actual experiment produced 0.94 wt% FFA content and 93.9 vol% washed second-esterified oil yield. The entire process required an average electricity of 0.137 kWh/L to reduce the FFA level in the SPO below 1 wt%.

Selective Production of Bio-Based Linear Alpha-Olefin from Wasted Fatty Alcohol on Al2O3 for Bio-Based Chemicals

The catalytic dehydration of a bio-based fatty alcohol was performed using Al2O3 prepared by solvothermal synthesis for selective production of long-chain linear-alpha-olefins (LAO). The effect of the synthesis temperature of alumina precursors on the dehydration of 1-octadecanol (C18H38O) was examined based on the textural properties and Lewis acid-base properties of the catalysts. Amorphous alumina synthesized at 325 °C showed the highest surface area (233.07 m2/g) and total pore volume (1.237 cm3/g) among the catalysts and the best dehydration results: 93% conversion, 62% selectivity of 1-octadecene (C18H36), and 89% LAO purity. This was attributed to the increased Al/O ratio and atomic concentration of surface O in alumina, which were important factors in the catalytic dehydration of 1-octadecanol through the synergistic catalysis of acid-base pairs. The produced bio-based LAO can be key intermediates for synthesis of oxo alcohols and poly-alpha-olefins, as alternatives to petroleum-based LAO to achieve carbon neutrality in chemical industry.

Integrated Cleaner Biocatalytic Process for Biodiesel Production from Crude Palm Oil Comparing to Refined Palm Oil

An integrated cleaner biocatalyst process was performed for biodiesel production from crude palm oil (CPO) and refined palm oil (RPO). It was evaluated on process efficiency in terms of high purity of biodiesel as well as by-products without purification, less wastewater, less time consuming, and a simple downstream process. A first saponification step was carried out in both f CPO and RPO, a high purity of glycerol (86.25% and 87.5%) was achieved, respectively, while free fatty acids (FFASs) in soap were obtained after hexane extraction. High yields of FFASs were obtained from both CPO and RPO (98.83% and 90.94%). Subsequently, the FFAs were esterified to biodiesel by a biocatalyst of immobilized lipase. The highest biodiesel yields achieved were of 92.14% and 92.58% (CPO and RPO). Remarkably, biodiesel yields obtained from CPO and RPO achieved satisfactory values and the biocatalyst used could be reused for more than 16–17 cycles.

Biojet Fuel Production from Waste of Palm Oil Mill Effluent through Enzymatic Hydrolysis and Decarboxylation

Palm oil mill effluent (POME), wastewater discharged from the palm oil refinery industry, is classified as an environmental pollutant. In this work, a heterogeneous catalytic process for biojet fuel or green kerosene production was investigated. The enzymatic hydrolysis of POME was firstly performed in order to obtain hydrolysed POME (HPOME) rich in free fatty acid (FFA) content. The variations of the water content (30 to 50), temperature (30 to 60 °C) and agitation speed (150 to 250 rpm) were evaluated. The optimal condition for the POME hydrolysis reaction was obtained at a 50% v/v water content, 40 °C and 200 rpm. The highest FFA yield (Y FA) of 90% was obtained. Subsequently, FFA in HPOME was converted into hydrocarbon fuels via a hydrocracking reaction catalysed by Pd/Al2O3 at 400 °C, 10 bars H2 for 1 h under a high pressure autoclave reactor (HPAR). The refined-biofuel yield (94%) and the biojet selectivity (57.44%) were achieved. In this study, we are the first group to successfully demonstrate the POME waste valorisation towards renewable biojet fuel production based on biochemical and thermochemical routes. The process can be applied for the sustainable management of POME waste. It promises to be a high value-added product parallel to the alleviation of wastewater environmental issues.

Synthesis of biodiesel from Annona muricata - Calophyllum inophyllum oil blends using calcined waste wood ash as a heterogeneous base catalyst

Naturally, biodiesel synthesized from highly viscous and high-density vegetable oil is usually unsuitable as fuel in the internal combustion engine. However, mixing/blending of two or more oils as a feedstock for biodiesel production could produce a low viscous fuel suitable for the engine. This study produced a novel heterogeneous base catalyst from waste wood ash (WWA) and applied it to synthesis of biodiesel from Annona muricata and Calophyllum inophyllum oilseed blend. The production route was via a two-step process due to the high free fatty acid of the blended oil. Process optimization of the transesterification step was carried out via response surface methodology (RSM). The strength of the developed catalyst was tested through catalyst regeneration and recyclability. The quality of the biodiesel was compared with biodiesel recommended standard.•Waste wood ash contained a high percentage of calcium carbonate•Blended oil produced oil of low viscosity•Two-step production route was used for biodiesel synthesis•Process optimization via hybrid design produced optimum biodiesel yield.

Techniques for analysing and monitoring during continuous bio-hydrogenation of kerosene from palm oils

In this research work, analytical, experimental methods and monitoring techniques of bio-hydrogenated kerosene (BHK) production in continuous mode were presented. Two kinds of raw materials obtained from palm processing plant named as refined bleached deodorised palm oil (RPO) and palm kernel oil (PKO) were converted into BHK via hydrocracking reaction catalysed by Pd/Al₂O₃ catalyst in pilot scale. Firstly, both of RPO and PKO were pretreated by thermal technique. Subsequently, fatty acid compositions of palm oils were analysed by Gas Chromatography (GC). Then, hydrocracking reaction of RPO and PKO were separately conducted in continuous high pressure packed bed reactor (HPPBR). After reaction, crude-biofuel was refined into BHK via fractional distillation. In addition, some properties of BHK obtained from RPO/PKO such as were C, H, O elements, freezing point, flash points, total acid number and carbon distribution were analysed following the ASTM and UOP 915 standards.•

Thermal pretreatment of refined bleached deoderised palm oil (RPO) and palm kernel oil (PKO).

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Continuous hydrocracking reaction of palm oil was conducted in pilot scale.

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Characterisation of bio-hydrogenated kerosene obtained from palm oil.

Entrapping Immobilisation of Lipase on Biocomposite Hydrogels toward for Biodiesel Production from Waste Frying Acid Oil

A new application of biocomposite hydrogels named gelatin-alginate (GA) and pectin alginate (PA) enables the use of the hydrogels as carriers for lipase entrapment during biodiesel production. Waste frying acid oil (WFAO), a raw material, was converted to biodiesel via an esterification reaction catalysed by two different immobilised biocatalysts: gelatin-alginate lipase (GAL) and pectin-alginate lipase (PAL). The highest immobilisation yield of GAL and PAL beads was achieved at 97.61% and 98.30%, respectively. Both of them gave biodiesel yields in the range of 75–78.33%. Furthermore, capability and reusability of biocatalysts were improved such that they could be reused up to 7 cycles. Moreover, the predicted biodiesel properties met the European biodiesel standard (EN14214). Interestingly, entrapped lipase on composite hydrogels can be used as an alternative catalyst choice for replacing the chemical catalyst during the biodiesel production.