Enhanced biomass production of <i>Scenedesmus obliquus</i> in a flat-panel photobioreactor, grown in photoautotrophic mode

<p>A study on biomass accumulation was conducted with <i>Scenedesmus obliquus</i> CCAP 276/3A in flat-panel photobioreactor, grown in photoautotrophic mode. It is one of the prime prerequisites to increase the economic feasibility and acceptance of microalgal feedstock for biofuel production, besides high lipid concentration. Various physicochemical parameters considered for evaluation during the present study were illumination conditions between 50 and 200 µmol m⁻² s⁻¹, temperatures between 22 and 30°C, pH varying from 7 to 9, and with and without the use of buffers. Among the variables, growth temperature and buffering with TRICINE had a pronounced effect on the enhanced biomass production. With an illumination intensity of 150 µmol m⁻² s⁻¹ at 24°C in the TRICINE-buffered Bold's Basal medium (pH 8.5) the maximum biomass concentration achieved was 1.76 gL^-1. The specific growth rate of the microalga was found to be 1.28 d⁻¹. Under these optimized conditions, the maximum lipid accumulation in <i>Scenedesmus obliquus</i> was found to be 33% (w/w). The compositional analysis of the neutral lipids indicated the predominance of palmitic acid and linoleic acid, accounting for 28% and 22.5%, respectively.</p

BATCH STUDIES FOR TRANSESTERIFICA TION OF ACID OIL FOR BIODIESEL PRODUCTION USING HETEROGENEOUS CATALYST

The predicted shortage and high price of crude oil encouraged the search for substitute for petroleum derivatives. In the present scenario, Biodiesel, alkyl ester of fatty acid/ vegetable oil (edible/ non-edible) may be one of the option. In a developing country like India, the prohibitive cost of vegetable oil prevent their use for biodiesel production. Therefore, non-conventional feed stocks like Palm fatty acid distillate, Fatty of refined oil, acid oil etc. have emerged as the newest raw materials for the production of biodiesel. In the present study, attempts were made for production of fatty acid methyl ester (FAME) from acid oil having high FFA. Batch studies for transesterification/ esterification were carried out to optimize the reaction parameter including the influence of : reaction temperature range 150-200 DC, mole ratio 1:6 to 1:20 quantity of solid catalyst 0.5-2% (by wt.) and reaction time 30-300 min. The process becomes more viable in many respects: tolerance of high FFA, moisture, lesser down stream processing, better quality of by-product glycerin. The biodiesel quality produced by the above process meets the specification as per ASTM/BIS. Further, the purity of biodiesel was found to be more than 99% confirmed by HPLC analysis

Novel Triazine Schiff Base-Based Cationic Gemini Surfactants: Synthesis and Their Evaluation as Antiwear, Antifriction, and Anticorrosive Additives in Polyol

Two novel triazine Schiff base-based cationic gemini surfactants namely N,N′-bis{(p-(N,N,N-tetradecyldimethylammonium bromide)- benzylidene} 6-methyl-1,3,5-triazine-2,4-diamine (14-MTR-14) and N,N′- bis{(p-(N,N,N-tetradecyldimethylammonium bromide)benzylidene} 6-phenyl- 1,3,5-triazine-2,4-diamine (14-PTR-14) were synthesized following the two- step reaction. First the intermediate adduct was synthesized by reaction of the 4-(dimethylamino)benzaldehyde with 1-bromotetradecane. In the second step, the germinal surfactants 14-MTR-14 and 14-PTR-14 were synthesized by imine coupling with this intermediate adduct with 6-methyl-1,3,5-triazine-2,4- diamine and 6-phenyl-1,3,5-triazine-2,4-diamine, respectively. Both were characterized using elemental analysis (CHN), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetry (TG). The compounds were then evaluated as anticorrosive and lubricity improver additive in polyol lube base oil. Both the surfactants show the similar anticorrosive activities. The antiwear and antifriction characteristics were estimated in terms of average wear scar diameter (AWSD) and average friction coefficient using a four ball test following ASTM D4172B. It was found that the 14-MTR-14 is comparatively more effective than 14-PTR-14. 14-MTR-14 reduces the AWSD of the polyol from 690 to 575.83 μm while the average friction coefficient decreases from 0.110 to 0.082 at 4000 ppm doping concentration

PERFORMANCE EVALUATION OF A PASSENGER CAR FUELLEDWITH BLENDSOF JATROPAMETHYL ESTER/ETHYL ESTERWITH DIESEL

Recent concerns over the environment, increasing fuel prices and scarcity of its supply have promoted the interest in the development of the alternative sources for petroleum fuels. Many researchers have reported the use of vegetable oil ester as a fuel in diesel engine, thereby achieving reduction in harmful exhaust emissions as well as a comparable engine performance as that with diesel. However, study on chassis dynamometer and in the field related to fuel economy, acceleration was undertaken in order to understand the impact of blending vegetable oil esters with the diesel in vehicles. This paper presents the result of the investigation carried out on a diesel passenger car on chassis dynamometer using diesel, 10%, 20% and 30% blend of bio-diesel (JME) and (JEE) fuels. The vehicle performance study have been carried out with the aim of obtaining comparative measures of the constant speed fuel consumption, driving cycle fuel economy, WOT Power, fuel consumption. The emission of the CO2 was also computed using the fuel economy data on the above-mentioned fuels. The vehicle acceleration tests were also carried out on actual road condition using global positioning systems (GPS) and the results for maximum speed, time elapsed for a distance of the 1km and also the acceleration time for reaching speeds of 0-60 km/hr and 0-90 km/hr are reported in the paper

Use of an Acylated Chitosan Schiff Base as an Ecofriendly Multifunctional Biolubricant Additive

Two acylated chitosan Schiff base samples ACSB-1 and -2 were synthesized via a two-step reaction pathway. First the chitosan Schiff base (CSB) was prepared utilizing 3,5-di-tert-butyl-4-hydroxybenzaldehyde. In the second step, esterification with lauroyl chloride catalyzed by 4-(dimethylamino)pyridine (DMAP) in N,N-dimethylacetamide (DMAc) solvent affords the final product acylated chitosan Schiff base (ACSB-1 and -2). The products were identified and characterized by Fourier transform infrared (FT-IR) spectroscopy, CHN analysis, thermogravimetry (TG), X-ray diffraction (XRD), etc. The synthesized compounds were evaluated as multifunctional additives for antioxidant and lubricity properties in N-butyl palmitate/stearate. A rotating pressure vessel oxidation test (ASTM D2272) was used for evaluating antioxidant property. The thermo-oxidative stability of the N-butyl palmitate/stearate oil was increased 1.5 times by using this additive in 3000 ppm concentration of ACSB-2 at 150 °C. Lubricity property was evaluated by using the four ball test (ASTM D4172A) which was performed at 75 °C tem- perature, frequency of 1200 rpm, and 198 N load for 60 min. The lubricating efficiency of the synthesized sample was estimated by measuring the average wear scar diameter (WSD) of the spherical specimen. The WSD is also found to be decreased significantly by adding these compounds as additives in N-butyl palmitate/stearate. Both samples passed the copper strip corrosion test (ASTM D130) too

Evaluation of a Novel Hindered Phenolic Triazine Schiff Base as Multifunctional Additive in Biolube and Biodiesel

A novel hindered phenolic triazine Schiff base TrBzEd was synthesized. At first the intermediate triazine Schiff base TrBz was synthesized by imine coupling of the 2-chloro-4,6-diamino-1,3,5-triazine with 3,5-di-tert-butyl- 4-hydroxybenzaldehyde. In the second step, additive TrBzEd was synthesized by reacting TrBz with the ethylenediamine. After characterization by CHN, FT-IR, NMR and TG, TrBzEd was evaluated as antioxidant and lubricity improver additive in both the polyol (biolube reference fluid) and biodiesel (Jatropha curcas). The RBOT and Rancimat tests were done to evaluate the antioxidant performance in polyol and biodiesel respec- tively. Lubricity improving characteristics were evaluated by doing four-ball test with polyol blend and HFRR test with biodiesel blends with TrBzEd in different concentra- tions. It was found that the TrBzEd improves the oxidative stability of the polyol significantly as the RBOT time of the blank polyol was found to be increased from 6.72 ± 0.15 to 12.57 ± 0.09 min at 2000 ppm concentration. It also showed moderate antiwear and antifriction characteristics in it. Antioxidant performance of this additive in biodiesel too was found to be excellent as Rancimat induction period at 1500 ppm additive concentration was found to be 13.14 ± 0.07 h which was high in comparison to the un- doped biodiesel by 2.19 times

Use of an Acylated Chitosan Schiff Base as an Ecofriendly Multifunctional Biolubricant Additive

Two acylated chitosan Schiff base samples <i>ACSB-1</i> and -<i>2</i> were synthesized via a two-step reaction pathway. First the chitosan Schiff base (<i>CSB</i>) was prepared utilizing 3,5-di-<i>tert</i>-butyl-4-hydroxybenzaldehyde. In the second step, esterification with lauroyl chloride catalyzed by 4-(dimethylamino)­pyridine (DMAP) in <i>N</i>,<i>N</i>-dimethylacetamide (DMAc) solvent affords the final product acylated chitosan Schiff base (<i>ACSB-1</i> and -<i>2</i>). The products were identified and characterized by Fourier transform infrared (FT-IR) spectroscopy, CHN analysis, thermogravimetry (TG), X-ray diffraction (XRD), etc. The synthesized compounds were evaluated as multifunctional additives for antioxidant and lubricity properties in <i>N</i>-butyl palmitate/stearate. A rotating pressure vessel oxidation test (ASTM D2272) was used for evaluating antioxidant property. The thermo-oxidative stability of the <i>N</i>-butyl palmitate/stearate oil was increased 1.5 times by using this additive in 3000 ppm concentration of <i>ACSB-2</i> at 150 °C. Lubricity property was evaluated by using the four ball test (ASTM D4172A) which was performed at 75 °C temperature, frequency of 1200 rpm, and 198 N load for 60 min. The lubricating efficiency of the synthesized sample was estimated by measuring the average wear scar diameter (WSD) of the spherical specimen. The WSD is also found to be decreased significantly by adding these compounds as additives in <i>N</i>-butyl palmitate/stearate. Both samples passed the copper strip corrosion test (ASTM D130) too