Process optimization and technoeconomic assessment of biodiesel production by one-pot transesterification of Ricinus communis seed oil.

In the present study, Ricinus communis seed oil with high free fatty acid content was utilized for the one-pot biodiesel production using 1-(2,3-dihydroxy)-propyl-3-methylimidazolium hydroxide, a basic ionic liquid catalyst. The 97.83% biodiesel yield was obtained at the optimized conditions of 6.26 % (w/w) of catalyst concentration, 10.51:1 M ratio of methanol to oil, 57.87 °C temperature and reaction time of 61.01 min. The transesterification of Ricinus communis seed oil to biodiesel exhibited an activation energy of 37.60 kJ/mol. The technoeconomic analysis, the profitability and the sensitivity analysis were investigated for the simulated process design. The technoeconomic analysis reported a total revenue of 20,455,431 $/yr, with gross margins, ROI, payback period, IRR, and NPV of 23.54%, 35.72%, 2.8 years, 28.20%, and 19,287,000 $, respectively. According to the sensitivity analysis, the two most important factors determining the economic viability of the simulated process are Ricinus communis seed oil cost and biodiesel selling price.

Fractionation, characterization, and economic evaluation of alkali lignin from saw industry waste.

The present work was focused on the investigation of lignin isolation from saw industry biomass (sawdust (SD)) using alkali solution, and to perform economic analysis for 2000 kg/batch hypothetical plant using techno-economic analysis. The isolated lignin was fractionated using organic solvent to obtain purified lignin. FTIR and 1H NMR analysis were performed to examine the structural characteristics of lignin. Lignin nanoparticles (LN) showed higher total phenolic content (TPC) (244.1 ± 2 µg of GAE per mg) and antioxidant activity (63.2 ± 1.7%) compared with crude lignin (CL), ethanol fractionated lignin (EL), and acetone fractionated lignin (AL). SuperPro designer was exposed to design and simulated 2000 kg/batch of sawdust fractionation process. The techno-economic analysis estimated that the lignin production cost is about $ 487,000 per year, and the annual revenue could be $ 1,850,000 per year. The techno-economic analysis and sensitivity analysis could be useful for the industrial level sawdust fractionation process.

Fractionation and characterization of lignin from waste rice straw: Biomass surface chemical composition analysis.

Waste rice straw (RS) was fractionated to extract the lignin using alkaline (sodium hydroxide) treatment (SHT) and organic acid (Formic acid/Acetic acid) treatment (OAT) process. Rice straw fractionation by the acetic OAT and alkaline SHT methods resulted in the recovery of OAT-lignin and SHT-lignin respectively. The structural characterization of the extracted lignin fractions was done by UV-vis spectroscopy, FTIR and 1H NMR technique. Total phenolic content (TPC) present in SHT-lignin and OAT-lignin were determined to be 28.87 mg GAE/g and 24.75 mg GAE/g respectively. The DPPH radical scavenging activity 59.50% was observed in SHT-lignin and 45.74% in OAT-lignin using the DPPH test for 30 min of incubation. Surface characterization of untreated rice straw (UT-RS) and treated rice straw (SHT-RS and OAT-RS) were carried out by XRD, FTIR and SEM. X-ray photoelectron spectroscopy (XPS) survey, C1s, and O1s spectra were used to determined the surface carbon and oxygen composition changes in RS after SHT and OAT. These structural characterizations of lignin and biomass are beneficial for further processing in bio-refinery industry.

A sequential pretreatment of lignocelluloses in bamboo biomass to fermentable sugars by acid/enzymatic hydrolysis.

A sequential pretreatment method for hydrolyzing rigid hemicelluloses and cellulose content in the bamboo biomass was investigated in this study. The effects of different parameters, such as nature of biomass, type of acid, acid and biomass concentration, were studied. Under the optimum condition of 5% (v/v) HCl-treated biomass and biomass concentration (8%, w/v), the maximum yield of sugar (619 mg/g of biomass) was obtained. The enzymatic hydrolysis parameter conditions were further optimized by response surface methodology-based central composite method. According to the results, the highest yield of sugar (515 mg/g of biomass) was obtained at hydrolysis temperature 50 °C, biomass concentration 8.9%, w/v, enzyme concentration (199.8 mg/g of biomass) and time 60 h, respectively. The effects of untreated, pretreated and enzymatically hydrolyzed biomass structure and complexity were investigated by field emission scanning electron microscopy and X-ray diffraction techniques.

Immobilized lipase catalyzing glucose stearate synthesis and their surfactant properties analysis.

Sugar fatty acid esters are practical importance and have a variety of applications that include surfactants and as an emulsifying agent. In this study, we report glucose stearate synthesis using lipase-Fe3O4 nanoparticles catalyst. The influence of various reaction factors, such as silica gel concentration, molar ratio of sugar/acid, reaction temperature and speed of agitation on esterification by immobilized enzyme was analyzed. The glucose stearate esterification degree of 87.2 % was obtained under the optimized condition: 1:2 molar ratio of glucose/stearic acid, 2 % (w/v) of silica gel at 120 rpm and 40 °C. Glucose esters were characterized according to their surfactant activity like emulsification index, oil displacement activity and antimicrobial activity. The results indicated glucose stearate acts as biosurfactant, with emulsification index of 66 % in mustard oil and oil displacement activity of 19.64 cm2.

Statistical optimization of process parameters for exopolysaccharide production by Aureobasidium pullulans using sweet potato based medium.

Statistical experimental designs were applied to optimize the fermentation medium for exopolysaccharide (EPS) production. Plackett-Burman design was applied to identify the significance of seven medium variables, in which sweet potato and yeast extract were found to be the significant variables for EPS production. Central composite design was applied to evaluate the optimum condition of the selected variables. Maximum EPS production of 9.3 g/L was obtained with the predicted optimal level of sweet potato 10 %, yeast extract 0.75 %, 5.5 pH, and time 100 h. The determined (R 2) value was 0.97, indicating a good fitted model for EPS production. Results of this study showed that sweet potato can be utilized as a low-cost effective substrate for pullulan production in submerged fermentation.