Synthesis of biomethane from obnoxious weed parthenium hysterophorous using biocatalyst in semi-batch anaerobic digester

In today’s world due to rapid urbanization and industrialization the global energy demand is increasing rapidly and about 88% of this demand is ruled over at present by fossil fuels. The dependence on fossil fuel as primary energy source has led to environment degradation and human health problems. To mitigate these problems, an alternative energy resource which can meet the sufficient demand is Biogas production from wastes. A promising alternative raw material for the accomplishment of Biomethanation is utilization of renewable lignocellulosic biomass. Parthenium hysterophorus L, an obnoxious flowering plant, offers a big challenge to all attempts of control because of its high regeneration capacity, production of huge amounts of seeds, high seed germinabilty and extreme adaptability to wide range of ecosystems. An experimental study on biomethanation using bio-waste – Parthenium hysterophorus was utilised to optimize the yield of methane gas with cow urine used as a catalyst. The experimental study was carried out under anaerobic condition in a semi-batch digester over the influence of pH (6-7.5), temperature (30-40 °C). In this study, pH, temperature, total solid (TS) and volatile fatty acid (VFA) and chemical oxygen demand (COD) were measured during the experiment. In the experiment it was found that using different parametric range like pH 6.5-7.5, temperature 35-40 °C and total solid (TS) 7.5 - 8.1%, the volatile fatty acid (VFA) yield was 128-942 mg/L and the maximum amount of methane produced was 62%

Parametric optimization of delignification of rice straw through central composite design approach towards application in grafting

The present investigation deals with process optimisation of delignification of rice straw towards its micro-porous structural enhancement for its utilization in polymer grafting. The individual effect of influential parameters viz. sodium hydroxide concentration (1–12%, w/v), reaction time (30–126 min), and temperature (20–150 °C) on delignification were studied in a single mode batch process. The process parameters were further optimized with Central composite design (CCD) approach of response surface methodology in Design expert software. Delignification of rice straws was observed to follow quadratic equation. Analysis of variance (ANOVA) study suggested the equation to be significant for the process with major impact of sodium hydroxide concentration on the delignification process than reaction time and temperature. The optimized parametric conditions of delignification are: alkali concentration 7.59%, reaction time 75.11 min, and reaction temperature 40 °C. The software predicted lignin extraction concentration to be 72.4 mg/g, which upon experimentation was found to be 70.03 mg/g. Instrumental analysis of the delignified rice straw demonstrated porous structure and change in surface chemistry due to lignin removal. Therefore, the delignified rice straw obtained under optimized conditions were found to be appropriate for grafting of polymers which improved its resilience for variable usages. Keywords: Rice straw, Delignification, Alkali treatment, Optimization, Central composite desig

Biosorptive uptake of arsenic(V) by steam activated carbon from mung bean husk: equilibrium, kinetics, thermodynamics and modeling

Abstract The present investigation emphasizes on the biosorptive removal of toxic pentavalent arsenic from water using steam activated carbon prepared from mung bean husk (SAC-MBH). Characterization of the synthesized sorbent was done using different instrumental techniques, i.e., SEM, BET and point of zero charge. Sorptive uptake of As(V) over steam activated MBH as a function of pH (3–9), agitation speed (40–200 rpm), dosage (50–1000 mg) and temperature (298–313 K) was studied by batch process at arsenic concentration of 2 mg L−1. Lower pH increases the arsenic removal over the pH range of 3–9. Among three adsorption isotherm models examined, Langmuir model was observed to show superior results over Freundlich model. The mean sorption energy (E) estimated by Dubinin–Radushkevich model suggested that the process of adsorption was chemisorption. Thermodynamic parameters confer that the sorption process was spontaneous, exothermic and feasible in nature. The pseudo-second-order rate kinetics of arsenic gave better correlation coefficients as compared to pseudo-first-order kinetics equation. Three process parameters, viz. adsorbent dosage, agitation speed and pH were opted for optimizing As(V) elimination using central composite design matrix of response surface methodology (RSM). The identical design setup was used for artificial neural network (ANN) for comparing its prediction capability with RSM towards As(V) removal. Maximum arsenic removal was observed to be 98.75% at sorbent dosage 0.75 gm L−1, pH 3.0, agitation speed 160 rpm and temperature 308 K. The study concluded that SAC-MBH could be a competent adsorbent for As(V) removal and ANN model was better in arsenic removal predictability results than RSM model

Free radical induced grafting of acrylonitrile on pre-treated rice straw for enhancing its durability and flame retardancy

The present investigation highlights the feasibility of a polymer grafting process to enhance the durability and flame retardancy of rice straw towards application as a low cost roofing material. The success of this grafting methodology was perceived to depend upon a bi-step pre-treatment process encompassing delignification and inorganic salts dispersion. Subsequently free radical polymer grafting of acrylonitrile onto rice straw was implemented by immersion mechanism initiated by oxalic acid-potassium permanganate initiator. The percentage of grafting, limiting oxygen index (LOI), biodegradability of the grafted rice straw and grafting yield percentage was estimated to be 57%, 27%, 0.02% and 136.67%, respectively. The weight loss of polymer grafted rice straw implied its less biodegradability over raw straw. Thus, the process of grafting contrived in the present analysis can be a promising and reliable technique for the efficient utilization of rice straw as an inexpensive roofing element through the augmentation of its durability and flame retardancy

Methanogenesis of organic wastes and their blend in batch anaerobic digester: Experimental and kinetic study

The scarcity of the fossil fuels and increasing energy demand urges the production of sustainable source of energy. The uncontrolled generation of wastes and their easy accessibilities gained a significant attention towards its use for the synthesis of renewable energy like biomethane. In order to cope up with the energy demand and urgency of alternative non-conventional energy source, the present study is focused on improvisation of biogas production qualitatively and quantitatively from different substrates viz. paper waste, Parthenium hysterophorus, canteen waste, and their mixture. The enhancement of the methane potential is accomplished by treating these substrates with catalyst (poultry litter, silica gel and cow urine) and active inoculum (gobar gas slurry) under the standard anaerobic digestion condition. The methanogesis process was carried out in a 1 l batch digester at 1:1 ratio of water:feed under mesophilic temperature (37 °C) for hydraulic retention time of 30 days. Moreover, cumulative gas yield for considered substrates were 167.32 ml/g VS, 149.05 ml/g VS, 197.72 ml/g VS, 290.69 ml/g VS respectively with methane content in biogas for each substrate of 25.5%, 56.8%, 60%, 62% respectively. Among various kinetic models studied, first order kinetic model was found to be best to describe the kinetics of biomethane synthesis for all employed wastes with maximum fitting accuracy (R2 = 0.966). Results of the study confirm the enrichment of quality and quantity of the product gas. The experimental study also revealed that the process is prominent for the efficient production of biomethane to meet the excessive energy thrust

Integrated trauma management system

Trauma has a huge impact on the society and the economy. Large distances between the various human settlements in Queensland are a major challenge for the delivery of desired trauma care. In addition, health care budget has been struggling due to staggering costs. An integrated trauma management system (ITMS) is expected to maximise the appropriate and judicious use of available resources and deliver best possible services within budget constraints. A limited number of researches have been conducted to identify resource constraints and effective diversions for trauma cases in remote parts of Queensland. ITMS proposed in this paper covers activities, events and persons involved in trauma management. It analyses the impact of resource constraints and diversion rules for effective trauma care. Pre-hospital data are used for developing a process map. Simulation using Queensland scenarios assumed patients arrivals following the referral from regional/remote hospitals to regional trauma centres and to major trauma centres. Time stamps are used for the development and analysis of a simulation model using probabilistic approach for time to definitive care and patient outcomes. ITMS is able to further enhance quality of strategic planning. It can be extended to real time decision-making for better healthcare and reducing delays for arriving at definitive care. It is expected to further improve clinical outcome and transform the existing healthcare system into a more efficient, cost-effective and high quality healthcare service to the people living in remote areas

Low-cost removal of basic red 9 using cow dung ash

In the present study, basic red 9 had been removed from synthetic waste water using animal waste. Cow dung ash had been prepared and characterized by scanning electron microscope. Morphology analysis shows very fine particles of less than 1 μm. The pH analysis study favours a pH of 8.5 for maximum dye removal. The removal of basic red 9 was very fast on cow dung ash. Percentage dye removal was 80.24% and 95.24 in 5 minutes and 90 minutes, respectively at initial dye concentration of 10 ppm

Research data supporting Microwave-assisted valorization of glycerol to solketal using biomass-derived heterogeneous catalyst

Research data supporting the full paper entitled "Microwave-assisted valorization of glycerol to solketal using biomass-derived heterogeneous catalyst " by S. Ao et al. in Fuel, 2023, 345, 128190. A heterogeneous biomass-based carbonaceous solid acid catalyst (SAFACAM) whose preparation we reported in https://doi.org/10.1016/j.renene.2021.12.001 was used multiple times in the production of solketal. The following supporting data are deposited here: X-ray powder diffraction (XRD) used a PANalytical X’Pert Pro diffractometer (Cu Kα radiation, 2theta = 10-60°, 100 mA current and 40 kV operating voltage). Brunauer-Emmet-Teller (BET) analysis used a Micromeritics ASAP 2010 surface area and porosity analyzer after sample degassing for 10 h and 150 °C. Thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) used a Metter Toledo TGA/DSC 1. Heating rate 10 °C min–1 and constant N2 flow in the range 50-600 °C. FT-IR analysis was by Nicolet iS50 spectrometer (Thermofisher). Solid-state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy used a Bruker AVANCE 400 MHz (9.4 T) instrument with a 4 mm double resonance probe. 1H-13C cross-polarization (CP) used 100 kHz 1H broadband SPINAL64, at 10 kHz MAS, 4 ms CP contact time (75 kHz ramped 1H, 65 kHz square 13C contact pulses), and a 2 s recycle delay. Shifts were referenced externally against the methylene 13C signal of glycine (43.1 ppm). 20 Hz exponential line broadening was applied when processing. Experiments used Bruker TopSpin 2.1. The catalyst was used to prepare solketal. Product analysis used an Agilent 7890 runing in head-space injector mode, and using a CPSIL 8CB capillary column (30 m × 0.25 mm × 0.25 μm) and a GC FID detector. Oven temperature was increased from 55 °C to 230 °C at 10 °C min–1. The temperature of the detector and the injector were 300 °C and 250 °C, respectively. Dimethyl sulfoxide internal standard. A Shimadzu QP 2010 Ultra mass spectrometer was used in HRMS. 1H and 1H 13C NMR spectra were obtained on a Bruker Avance II 500 MHz spectrometer. Deuterated solvent was stored over molecular sieves (3 Å). Chemical shifts were internally referenced to the deuterated solvent. Data collected at 28 °C

Biosorptive uptake of Fe2+, Cu2+ and As5+ by activated biochar derived from Colocasia esculenta: Isotherm, kinetics, thermodynamics, and cost

The adsorptive capability of superheated steam activated biochar (SSAB) produced from Colocasia esculenta was investigated for removal of Cu2+, Fe2+ and As5+ from simulated coal mine wastewater. SSAB was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller analyser. Adsorption isotherm indicated monolayer adsorption which fitted best in Langmuir isotherm model. Thermodynamic study suggested the removal process to be exothermic, feasible and spontaneous in nature. Adsorption of Fe2+, Cu2+ and As5+ on to SSAB was found to be governed by pseudo-second order kinetic model. Efficacy of SSAB in terms of metal desorption, regeneration and reusability for multiple cycles was studied. Regeneration of metal desorbed SSAB with 1 N sodium hydroxide maintained its effectiveness towards multiple metal adsorption cycles. Cost estimation of SSAB production substantiated its cost effectiveness as compared to commercially available activated carbon. Hence, SSAB could be a promising adsorbent for metal ions removal from aqueous solution

Sulphonated biomass-based catalyst for solketal synthesis by acetalization of glycerol – A byproduct of biodiesel production

Research on biomass-based catalyst is beneficial for the sustainability of biodiesel industry owing to its wide availability of feedstock, non-toxicity and biodegradability. Cellulose based heterogeneous solid carbon catalyst was prepared from cellulose by treating cellulose with concentrated sulphuric acid in innocuous hydrothermal conditions. It shows promising potential as a suitable catalyst for the synthesis of solketal (a biofuel additive) by acetalization of glycerol, the waste product of biodiesel production. 97.1 ± 0.4% of solketal was produced under the optimum conditions of 1:5 M ratio of glycerol and acetone, catalyst loading of 7 wt% at 70 °C in 10 min. 90% of catalytic activity was retained even after five catalytic cycles making the catalyst highly efficient. With further investments; this method may be used for the preparation of biofuel additive in an industrial level