Search

Graphical abstract Highlights • Monoraphidium sp. KMC4 found to be novel strain among eight other DSW isolates. • Biochemical, CHNS, TGA, FTIR validated KMC4′s potential as bioenergy feedstock. • FAME with 78% of C16/C18 confirmed the feasibility of biodiesel production. • LEMB characterization also suggested it as a high-value bioenergy feedstock. • Optimal biomass to energy conversion validated zero-waste biorefinery approach. Abstract The present study investigated the feasibility of domestic sewage wastewater (DSW) as an alternate to fresh-water microalgae growth media towards high-value bioenergy feedstock production. Eight native microalgal strains were screened from DSW and the effect of raw DSW (RDSW), and autoclaved DSW (ADSW) on growth and bioremediation potential were evaluated and compared with control BG11 medium. The study confirmed RDSW as a potential growth medium while Monoraphidium sp. KMC4 showed superior biomass (1.47 ± 0.08 g L−1) and lipid yield (436.01 ± 0.06 mg L−1). The corresponding values for bioremediation of ammonia, nitrate, phosphate, as well as COD remained within 88–100%. CHNS, biochemical, TGA, FTIR, FAME analysis of KMC4 confirmed it's potential as bioenergy feedstock. Additionally, a comprehensive characterization of lipid-extracted microalgae biomass (LEMB) was carried out which suggested that LEMB can be used as a growth promoter as well as feedstock for biogas, bioethanol, and bio-oil production. [ABSTRACT FROM AUTHOR]

Utilizing lignocellulosic biomass as a renewable energy source for the production of sustainable fuel is of paramount importance. This study focuses on the catalytic co-pyrolysis of Mesua ferrea L. de-oiled cake (MDC) and Garlic husk (GH) as potential feedstocks for bio-fuel production. The pyrolysis experiments were conducted using a semi-batch reactor under inert conditions at temperatures of 500, 550, and 600 °C, with a heating rate of 10 °C min−1, a particle size below 1 mm, and an inert gas flow rate of 80 mL min−1. The findings reveal that temperature significantly influences the yield of pyrolytic products. However, GC-MS analysis detected higher oxygenated compounds in the bio-oil, negatively impacting its heating value. To improve fuel quality, co-pyrolysis with and without a catalyst for a feedstock ratio of 1:1 w/w was performed. Red mud, an alkaline waste mainly composed of Fe2O3, Al2O3, and SiO2, is a hazardous environmental concern from aluminum production and is used as a catalyst. The red-mud catalysts reduced oxygen concentration and increased carbon content, acidity, and heating value in the pyrolytic oil. GC-MS analysis of the bio-oil confirmed that using catalysts combined with MDC and GH significantly decreased the concentration of acidic and aromatic compounds, thereby improving the pyrolytic oil's higher heating value (HHV). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thermal pyrolysis of Cassia siamea was studied. • Maximum yield was 39.86 wt% of organic liquid (oil) and 10.35 wt% of aqueous liquid. • Pyrolytic oil was basic with a pH of 8.75 and calorific value of 30.18 MJ kg−1. • Pyrolytic oil includes phenols, aromatics, esters, alkanes, acids, and nitriles. • Pyrolytic char was rich in carbon (57.34%) with a calorific value of 21.894 MJ kg−1. Abstract Thermal pyrolysis of the Cassia siamea seed was carried out in a fixed bed reactor in the temperature range of 450 °C and 575 °C at a heating rate of 50 °C min−1. The reactor was maintained inert using nitrogen gas at a flow rate of 40 mL min−1. It was observed that the highest yield of pyrolytic liquid was 50.21% obtained at 550 °C which includes 39.86 wt% of organic liquid (oil) and 10.35 wt% of aqueous liquid. The fuel properties of pyrolytic oil confirmed that the oil was slightly basic with a pH of 8.75, having viscosity and calorific value of about 373 cSt and 30.18 MJ kg−1 respectively. The GC-MS based composition analysis quantified the occurrence of many valuable bio-chemicals such as heptadecanenitrile, 1,2-benzene dicarboxylic acid, butyl octyl ester, phenol, p-cresol as major compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient treatment method for effluent media reuse was developed. • Effluent media concentration was optimized. • Advantages of PAC treatment was demonstrated. • 21.9% enhanced biomass yield obtained with 30% water savings. • Recyclability of treated media was studied under a biorefinery model. In this study, the suitability of cultivating Monoraphidium sp. KMC4 was exhibited in different effluent based culture (EBC) media concentrations, the latter being treated with powdered activated carbon (PAC) with a loading of 5–50 mg L-1. The optimum EBC media treated with 30 mg L-1 PAC enhanced the biomass yield by 21.9% as compared to the untreated one (1.21 g L-1). A recyclability study performed in five batches resulted in an optimal growth up to three batches with an overall biomass yield of 4.21 g and a total water savings of 30%. Additionally, physico-chemical characterization and FAME profile of the biomass from the recyclability study validated feedstock's energy potential. Moreover, this study proposes a biorefinery model which could recover nutrient rich liquid effluent (3.1 million litres) and solid residue for various applications along with the generation of 5760 kg of biomass followed by 113 L d-1 biodiesel yield. [ABSTRACT FROM AUTHOR]

Bio-energy from lignocellulosic biomass is cleaner, sustainable, and one of the renewable energy sources that could help meet some of our energy demand. Unlike fossil fuels, it can be grown and used repeatedly and its use can replace the fossil fuels. In addition to this, these materials are easily available either in the form of agricultural waste or forest residues and are economically viable. The current study focuses on physico-chemical characterisation of three commonly available lignocellulosic biomasses of north-east India such as Castor (Ricinus communis), Jatropha (Jatropha curcas), and Miscanthus (Miscanthus sinensis) for second generation biofuels production. Ultimate analysis (CHNSO), thermogravimetric analysis, X-ray diffraction, Fourier transformation infrared (FTIR), and oxygen bomb calorimeter techniques were used to characterise the above mentioned three lignocellulose biomasses. It was found that the cellulose content of three biomasses varied from 40% to 44%, hemicellulose content from 8% to 14%, and lignin content varied from 21% to 30%. Chemical structure of lignocellulose is studied through FTIR. The crystallinity index of Castor and Jatropha is similar, i.e., ~69%, where as crystallinity index of Miscanthus was 72%. Due to the presence of higher carbon and cellulose content along with less moisture (10%-12%), ash (5%-10%), sulphur (0.1%-0.8%), and extractives (12%-20%) make them a very good source for production of alcoholic fuels through a biochemical route. [ABSTRACT FROM AUTHOR]

The present study was designed to assess Messastrum gracile SVMIICT7 potential in treating dairy wastewater (autoclaved (ADWW) and raw (DWW)) with relation to nutrient removal, in-vivo Chl-a-based biomass, and bio-oil synthesis. Chlorophyll a fluorescence kinetics revealed improved photochemical efficiency (0.639, Fv/Fm) in M. gracile when grown with DWW. This may be owing to enhanced electron transport being mediated by an effective water-splitting complex at photosystem (PSII) of thylakoids. The increase in ABS/RC observed in DWW can be attributed to the elevated chlorophyll content and reduced light dissipation, as evident by higher values of ETo/RC and a decrease in non-photochemical quenching (NPQ). M. gracile inoculated in DWW had the highest Chl-a-biomass yield (1.8 g L−1) and biomolecules while maximum nutrient removal efficiency was observed in ADWW (83.7% TN and 60.07% TP). M. gracile exhibited substantial bio-oil yield of 29.6% and high calorific value of 37.19 MJ kg−1, predominantly composed of hydrocarbons along with nitrogen and oxygen cyclic compounds. This research offers a thorough investigation into wastewater treatment, illustrating the conversion of algal biomass into valuable energy sources and chemical intermediates within the framework of a biorefinery. [Display omitted] • Messastrum gracile SVMIICT7 thrived effectivey in both autoclaved and raw dairy wastewater (ADWW and DWW). • Chl-a fluorescence showed a significant correlation with residual TN, TP, and Carbon load resulting improved CO 2 fixation. • Messastrum sp. exhibited bio-oil yield of 29.6% and calorific value of 37.19 MJ kg−1 with diverse metabolite profile. • Self-sustained biorefinery approach for biosynthesis of value-added products with simultaneous treatment. [ABSTRACT FROM AUTHOR]

Fuels derived from biomass are renewable as well as environment friendly. In this study, three biomasses viz. husk of areca nut ( Areca catheu), trunks of moj ( Albizzia lucida), and bon bogori ( Ziziphus rugosus) available in North-East region of India were tested as potential biofuel sources. The accentuation of this study was to determine the kinetic parameters using thermogravimetric (TG) technique under air and nitrogen atmosphere. The experiments were carried out within temperature range 300-973 K under air and nitrogen atmosphere at four different heating rates viz. 5, 10, 15, and 20 K min, respectively. The mass losses at different lumps in the TG graphs were estimated. The first-order kinetic parameters such as activation energy and pre-exponential factor were calculated for different reaction zones for all the three biomass samples. Effects of atmosphere on combustion characteristics (e.g., peak temperature, ignition temperature, and reactivity index) of biomasses were also determined in this study. Areca nut husk has highest ignition temperature (526.38 K) and reactivity index (0.21) but moj has highest peak temperature (597.91 K) along with highest activation energy (348.04 kJ mol) and pre-exponential factor (1.12 × 10 min), respectively. [ABSTRACT FROM AUTHOR]

Abstract: The lignocellulosic materials are cheap and readily available either in the form of agricultural waste or forest residues. These materials can be used as a source for energy production either in the gaseous form (CO, H2 etc) or in liquid form (ethanol, butanol etc) to meet the rising demand of energy. The reign of lignocellulosic materials for energy production is a proven fact in this era of energy research. The present study focuses on characterization of three biomass samples namely areca nut husk (Areca catheu), moj (Albizia lucida) and bonbogori (Ziziphus rugosa), available in the region of North-East India. Physical and chemical analysis of these lignocellulosic biomass samples were performed using X-ray diffraction techniques, thermogravimetric analysis, FTIR, Raman spectroscopy and CHNSO analysis. Maximum crystalinity was observed in areca nut husk fiber (63.84%) followed by moj (46.43%) and bonbogori (42.46%). The calorific values of all the biomasses were found within the range of 17 MJ/kg to 22 MJ/kg. All these properties combined together per se shows that areca nut husk, bonbogori and moj are potential sources for biofuel production. [Copyright &y& Elsevier]

Pretreatment is an inevitable high energy consuming process en route to biofuel production which alters the recalcitrant structures of lignocellulosic biomass. An attempt has been made to pretreat the areca nut husk fibre using dilute sulphuric acid. The Taguchi robust design method of optimisation (L9 orthogonal array) was applied to this acid catalyzed pretreatment process. Cellulose crystallinity is directly proportional to the degree of enzymatic hydrolysis of any kind of cellulosic substrate; the present study considers it as an index to optimise the process parameters. The study showed that the sulphuric acid concentration plays the major role during the pretreatment of areca nut husk (57% contribution) followed by the duration of operation (24.98% contribution) and solid loading (14.3% contribution). The optimal factors obtained from the design of experiments were further validated using the experimental results. [ABSTRACT FROM AUTHOR]