Effect of Nitrogen Concentration on the Alkalophilic Microalga Nitzschia sp. NW129-a Promising Feedstock for the Integrated Production of Lipids and Fucoxanthin in Biorefinery

Microalgae are considered promising resources for producing a variety of high-value-added products, especially for lipids and pigments. Alkalophilic microalgae have more advantages than other microalgae when cultured outdoors on a large scale. The present study investigated the comprehensive effects of different nitrogen concentrations on fucoxanthin (Fx), lipids accumulation and the fatty acid profile of the alkaliphilic microalgae Nitzschia sp. NW129 to evaluate the potential for simultaneous production of Fx and biofuels. Fx and Lipids amassed in a coordinated growth-dependent manner in response to various concentrations, reaching 18.18 mg g–1 and 40.67% dry weight (DW), respectively. The biomass of Nitzschia sp. NW129 was 0.58 ± 0.02 g L–1 in the medium at the concentration of 117.65 mM. The highest productivities of Fx (1.44 mg L–1 d–1) and lipid (19.95 ± 1.29 mg L–1 d–1) were obtained concurrently at this concentration. Furthermore, the fatty acid methyl esters revealed excellent biofuel properties with an appropriate value of the degree unsaturation (49.97), cetane number (62.72), and cold filter plugging point (2.37), which met the European standards for biofuel production (EN14214). These results provided a reliable strategy for further industrialization and comprehensive production of biofuel and Fx by using the alkaliphilic microalgal Nitzschia sp. NW129.

Methcyclohexyl methacrylate-methacrylate copolymers：An effective cold flow improver for the biodiesel blends

The poor cold flow property is one of the main obstacle factors in affecting the utilization of high-proportional biodiesel blends in engines. In this study, methcyclohexyl methacrylate-methacrylate copolymers (MCHMA-R1MC, R1 = C12, C14, C16, C18) were synthesized at various molar ratios by radical polymerization and characterized by FTIR, GPC, and 1H NMR. Their structures and properties areanalyzed and characterized by FTIR, GPC, and 1H NMR. The resulting copolymers were tested as the cold flow improver in terms of cold filter plugging point (CFPP) and solid point (SP) measurement for treated and untreated B20 biodiesel blends (20 vol.% biodiesel + 80 vol.% diesel). Results showed that the CFPP and SP of B20 decreased to a varied extent after MCHMA-R1MC treatment. When the monomer ratio of is 1:7, MCHMA-C14MC (1:7) proved the greatest depression in CFPP and SP of B20 by 18 and 25℃ at 2000 ppm dosage. The effects of MCHMA-R1MC copolymers on crystal behavior was studied through polarizing optical microscope(POM), differential scanning calorimetry(DSC) and viscosity-temperature curves. The results indicated that MCHMA-C14MC could effectively delay the aggregation of wax crystals and change their crystalline behavior by changing the shape of the crystals and inhibiting the formation of large wax crystals, and then lower the low-temperature viscosity of biodiesel blends and make it exhibiting better cold flow properties.

Influence of Pressure on Product Composition and Hydrogen Consumption in Hydrotreating of Gas Oil and Rapeseed Oil Blends over a NiMo Catalyst

This study describes the co-hydrotreating of mixtures of rapeseed oil (0–20 wt%) with a petroleum feedstock consisting of 90 wt% of straight run gas oil and 10 wt% of light cycle oil. The hydrotreating was carried out in a laboratory flow reactor using a sulfided NiMo/Al2O3 catalyst at a temperature of 345 °C, the pressure of 4.0 and 8.0 MPa, a weight hourly space velocity of 1.0 h−1 and hydrogen to feedstock ratio of 230 m3∙m−3. All the liquid products met the EU diesel fuel specifications for the sulfur content (<10 mg∙kg−1). The content of aromatics in the products was very low due to the high hydrogenation activity of the catalyst and the total conversion of the rapeseed oil into saturated hydrocarbons. The addition of a depressant did not affect the cold filter plugging point of the products. The larger content of n-C17 than n-C18 alkanes suggested that the hydrodecarboxylation and hydrodecarbonylation reactions were preferred over the hydrodeoxygenation of the rapeseed oil. The hydrogen consumption increased with increasing pressure and the hydrogen consumption for the rapeseed oil conversion was higher when compared to the hydrotreating of the petroleum feedstock.

Investigating the effects of depressant additives on the low temperature properties of petroleum products

The article is devoted to the study of the low temperature properties of petroleum products and the influence of depressant additives on former. The objects of the study are the summer mark diesel fuel produced by «ПетроКоммерцОйлКазахстан» and depressant additives of «AGA», «MANNOL», «FENOM», «CYCLO C-24» brands. Such physical and chemical characteristics of petroleum products as flashpoint, pour point, cloud point, cold filter plugging point and kinematic viscosity of pure diesel fuel at the presence and absence of depressor additives of brands listed above. The best performance among studied additives is shown by «MANNOL» brand additive.

Investigating the effects of depressant additives on the low temperature properties of petroleum products

The article is devoted to the study of the low temperature properties of petroleum products and the influence of depressant additives on former. The objects of the study are the summer mark diesel fuel produced by «ПетроКоммерцОйлКазахстан» and depressant additives of «AGA», «MANNOL», «FENOM», «CYCLO C-24» brands. Such physical and chemical characteristics of petroleum products as flashpoint, pour point, cloud point, cold filter plugging point and kinematic viscosity of pure diesel fuel at the presence and absence of depressor additives of brands listed above. The best performance among studied additives is shown by «MANNOL» brand additive.

Improving the cold flow properties of biodiesel from waste cooking oil by ternary blending with bio-based alcohols and diesel from direct coal liquefaction

The utilization and popularization of biodiesel are always limited by its poor cold flow properties. Both bio-based alcohol and diesel from direct coal liquefaction (DDCL) has potential to enhance the cold flow properties of biodiesel. Ternary blends of waste cooking oil biodiesel (BWCO) with DDCL and bio-based ethanol (ET) or 1-butanol (BT) for improving the cold flow properties of biodiesel. The pour point (PP), cold filter plugging point (CFPP), and cloud point (CP) of BWCO-ET, BWCO-BT, and BWCO-DDCL binary blends, and BWCO-ET-DDCL and BWCO-BT-DDCL ternary blends were comparatively assessed. Ternary phase diagrams were also applied into analyze the blending effect of the three components on the cold flow properties of biodiesel. Results showed that both DDCL, ET and BT can remarkably enhance the cold flow properties of BWCO. BT and DDCL presented a better synergistic depression effect. For ternary blends in 20:10:70 blending ratio, BWCO-BT-DDCL exhibited the lowest PP, CFPP, and CP of −23 °C, −19 °C, and −17 °C, respectively. The crystallization behavior and crystal morphology of blended fuels are also observed via a polarizing optical microscope, and find that DDCL together with BT in biodiesel can effectively retard the aggregation of large crystals and inhibit crystals growth.

Simultaneous phycoremediation of petrochemical wastewater and lipid production by Chlorella vulgaris

A novel strategy of using microalgae Chlorella vulgaris for simultaneous bio-treatment of petrochemical wastewater and lipid production was developed in the present study. Phycoremediation was carried out in 30 days. The profile of fatty acids was identified, and the specifications of biodiesel including saponification value, iodine value, cetane number, long-chain saturated factor, cold filter plugging point, cloud point, allylic position equivalent and bis-allylic position equivalent were predicted by BiodieselAnalyzer® software. Besides, polycyclic aromatic hydrocarbons were determined in both wastewater samples and produced lipid. The observed data showed that biodiesel from C. vulgaris was superior to petrodiesel in terms of suitability in diesel engines. Moreover, contamination of petrochemical wastewater can influence the expression of a variety of genes in algae. To investigate the effectiveness of contamination on the expression of lipid synthesis as well as three photosynthesis genes, a real-time polymerase chain reaction assay was used to quantify transcript levels of PsaB (photosystem I reaction center protein subunit B), psbC (an integral membrane protein component of photosystem II), and rbcL (a large subunit of ribulose-1,5-bisphosphate carboxylase oxygenase). Furthermore, the gene expression level of accD (acetyl-coenzyme A carboxylase carboxyl transferase subunit beta, chloroplastic) was studied to discover the effect of wastewater on lipid production. The results showed that when diluted petrochemical wastewater (50%) was used as a media for C. vulgaris cultivation, these genes expression significantly increased. For 50% diluted wastewater, the maximum removal of BOD, COD, total nitrogen, and total phosphor has been 30.36%, 10.89%, 69.89%, and 92.59%, respectively.

Fluid Characteristics of Biodiesel Produced from Palm Oil with Various Initial Water Contents

Biodiesel is regarded as a significant alternative fuel to petrodiesel due to its excellent combustion features and renewable character. The water content in the reactant mixtures needs to be considered so as to retard the conversion rate and it is suggested to be kept as low as possible. The fluid characteristics of biodiesel might be affected by initial water content; however, the optimum ratio of water content added to raw oil for achieving superior fluid characteristics of biodiesel has not yet been studied. Hence, this study empirically investigated the influences of the initial water content added to raw feedstock oil on the fluid characteristics of biodiesel. The experimental results show that an adequate amount of water content in the reactant mixture was found effective for improving the transesterification reaction and, in turn, the fluid characteristics. The biodiesel made from raw oil with 0.05 wt. % water content added was observed to bear the lowest water content, acid value, and cold filter plugging point (CFPP) and, therefore, superior fluidity at low temperatures. The lower CFPP of biodiesel is attributed to its more unsaturated fatty acids and lower iodine value. In addition, the biodiesel produced from feedstock oil with 0.02 wt. % water added was observed to have the lowest iodine value but the highest kinematic viscosity. The optimum content of initial water added to palm oil for superior fluid characteristics of the biodiesel product is thus suggested to be in the range between 0.02 wt. % and 0.05 wt. %.

Potential Applications of Native Cyanobacterium Isolate (Arthrospira platensis NIOF17/003) for Biodiesel Production and Utilization of Its Byproduct in Marine Rotifer (Brachionus plicatilis) Production

To achieve strong, successful and commercial aqua-biotechnological microalgae applications, screening, isolation, molecular identification, and physiological characterizations are needed. In the current study, a native cyanobacteria strain Arthrospira platensis NIOF17/003 was isolated from the surface water of El-Khadra Lake, a saline-alkaline lake located in Wadi El-Natrun, Egypt. The cyanobacterium was phylogenetically identified by 16S rRNA molecular marker and deposited in the GenBank database (accession number MW396472). The late exponential phase of A. platensis NIOF17/003 was reached at the 8th day of growth using Zarrouk medium, with a recorded dry weight (DW) of 0.845 g L−1. The isolated strain showed 52% of protein, 14% of carbohydrate, biomass productivity of 143.83 mg L−1 day−1, 8.5% of lipid, and lipid productivity of 14.37 mg L−1 day−1. In general, the values of cetane number, iodine value, cold filter plugging point (52.9, 85.5 g I2/100 g oil, and −2.2 °C, respectively) of the isolated fatty acid methyl esters are in accordance with those suggested by international standards. Besides, applying algal-free lipid (FL) as biodiesel byproduct in the production of rotifer (Brachionus plicatilis) revealed that a 0.6 g L−1 FL significantly increased the rotifer population females carrying eggs, confirming that FL can be used efficiently for B. plicatilis production. The current study concluded that the new isolate A. platensis NIOF17/003 is a promising strain for double sustainable use in biodiesel production and aquaculture feed.

Experimental investigations on mixing of candle nut and soap nut biodiesels blended with diesel for diesel engines

Candle nut oil was produced from candle nut seeds by the process of crushing and filtering. The candle nut biodiesel was prepared by two-step co-solvent esterification process and is found to be a one of the best alternate fuel for running the diesel engine. The oxidation stability of the candle nut biodiesel was found to be poor and this leads to high acid value and inception of insoluble gums and dregs or scum that can block the fuel filters. Soap nut oil was extracted from soap nut seeds by the process of crushing and filtering. The soap nut biodiesel was prepared by transesterification process and has higher oxidation stability compared to candle nut biodiesel. Similarly, the cold filter plugging point of candle nut biodiesel is good compared to soap nut biodiesel and it depends upon the amount of saturated fat. Hence the mixing of soap nut biodiesel and candle nut biodiesel will increase the properties for the smooth run of engine with fewer emissions compared to diesel. In this work, engine performances and exhaust contents are evaluated for various blends of mixed soap nut biodiesel and Candle nut biodiesel.