Utilization of palm oil alkyl esters as an additive in ethanol-diesel and butanol-diesel blends

This research focuses on the use of biodiesel as an additive in diesohol preparation. Three types of biodiesel—methyl, ethyl, and butyl esters—were prepared from palm oil through transesterification using a conventional base catalyst. Ethanol is generally used to blend in diesohol; however, butanol is another alcohol which has higher solubility in diesel than ethanol and it can improve the fuel properties of the blends. Therefore, a comparative study of phase stability, the dependence of solubility on temperature (10, 20, and 30 °C), and an evaluation of some basic fuel properties according to the ASTM of diesel-biodiesel-ethanol and diesel-biodiesel-butanol three-component systems at different component concentrations was done. We found that the use of butanol in diesohol could solve the problem of fuel instability at low temperatures because of its higher solubility in diesel fuel. In addition, the fuel properties results indicated that blends containing butanol have properties closer to diesel than those of blends containing ethanol.     

Assessment of energy performance and air pollutant emissions in a diesel engine generator fueled with water-containing ethanol–biodiesel–diesel blend of fuels

Biomass based oxygenated fuels have been identified as possible replacement of fossil fuel due to pollutant emission reduction and decrease in over-reliance on fossil fuel energy. In this study, 4 v% water-containing ethanol was mixed with (65–90%) diesel using (5–30%) biodiesel (BD) and 1 v% butanol as stabilizer and co-solvent respectively. The fuels were tested against those of biodiesel–diesel fuel blends to investigate the effect of addition of water-containing ethanol for their energy efficiencies and pollutant emissions in a diesel-fueled engine generator. Experimental results indicated that the fuel blend mix containing 4 v% of water-containing ethanol, 1 v% butanol and 5–30 v% of biodiesel yielded stable blends after 30 days standing. BD1041 blend of fuel, which composed of 10 v% biodiesel, 4 v% of water-containing ethanol and 1 v% butanol demonstrated −0.45 to 1.6% increase in brake-specific fuel consumption (BSFC, mL kW⁻¹ h⁻¹) as compared to conventional diesel. The better engine performance of BD1041 was as a result of complete combustion, and lower reaction temperature based on the water cooling effect, which reduced emissions to 2.8–6.0% for NO_x, 12.6–23.7% particulate matter (PM), 20.4–23.8% total polycyclic aromatic hydrocarbons (PAHs), and 30.8–42.9% total BaPeq between idle mode and 3.2 kW power output of the diesel engine generator. The study indicated that blending diesel with water-containing ethanol could achieve the goal of more green sustainability.     

Production of liquid biofuels from renewable resources

This article is an up-to-date review of the literature available on the subject of liquid biofuels. In search of a suitable fuel alternative to fast depleting fossil fuel and oil reserves and in serious consideration of the environmental issues associated with the extensive use of fuels based on petrochemicals, research work is in progress worldwide. Researchers have been re-directing their interests in biomass based fuels, which currently seem to be the only logical alternative for sustainable development in the context of economical and environmental considerations. Renewable bioresources are available globally in the form of residual agricultural biomass and wastes, which can be transformed into liquid biofuels. However, the process of conversion, or chemical transformation, could be very expensive and not worth-while to use for an economical large-scale commercial supply of biofuels. Hence, there is still need for much research to be done for an effective, economical and efficient conversion process. Therefore, this article is written as a broad overview of the subject, and includes information based on the research conducted globally by scientists according to their local socio-cultural and economic situations.     

Catalytic valorization of bioethanol over Cu-Mg-Al mixed oxide catalysts

The conversion of ethanol into 1-butanol and 1,1-diethoxyethane was studied over Cu-Mg-Al mixed oxide catalysts obtained from LDH precursors. The optimum yields are obtained for Cu loadings comprised between 5 and 10 at.%. A reaction scheme accounting for the main and secondary reaction products is proposed. The influences of the reaction temperature and of the reaction time on the catalytic performances have also been investigated. The negative effect of water, a by-product of the reaction, on this transformation was evidenced.     

Conceptual design of an extractive distillation process for the separation of azeotropic mixture of n-butanol-isobutanol-water

In many chemical processes, large amounts of wastewater containing butanol and isobutanol are produced. Given that n-butanol-isobutanol-water can form triple azeotrope, high-purity butanol cannot be recovered from the wastewater by ordinary distillation. To economically and effectively recover butanol from this kind of wastewater, 1,4-butanediol is selected as an extractant to break the formation of the azeotropes, and a doubleeffect extractive distillation process is proposed. The conceptual design of the proposed process is accomplished based on process simulation. With the proposed process, the purity of recovered butanol and water is greater than 99.99 wt%. In comparison with the conventional azeotropic distillation process, economic analysis shows that the operating cost of the proposed process is lower:when the capacity of wastewater treatment is 100 t·h^-1, the total operating cost decreases by 5.385×10⁶ USD per year, and the total annual cost of the new process decreases by 5.249×10⁶ USD per year. In addition, in the extractive distillation system, variable effects on separation purities and cost are more complex than those in the ordinary distillation system. The method and steps to optimize the key variables of the extractive distillation system are also discussed in this paper and can provide reference for similar studies.     

Aerobic biodegradation of butanol and gasoline blends

This work aimed to assess the aerobic biodegradation of butanol/gasoline blends (5; 10; 15 and 20% v/v), being the latter compared to the ethanol/gasoline blend (20% v/v). Two experimental techniques were employed, namely the respirometric method and the redox indicator DCPIP test. In the former, experiments simulating the contamination of natural environments (addition of 50 mL of fuel kg⁻¹ of soil from a non-contaminated site and 20 mL of fuel L⁻¹ of water from a river) were carried out in biometer flasks (250 mL), used to measure the microbial CO₂ production. The DCPIP test assessed the capability of four inocula to biodegrade the blends of 20%. The addition of butanol at different concentrations enhanced the biodegradation of gasoline in soil. However, no practical gains were observed for concentrations of butanol above 10%. Ethanol showed to have a much faster biodegradation rate than butanol, particularly in water, and the following order of biodegradability was found: ethanol > butanol > gasoline. The addition of the alcohols to the gasoline resulted in positive synergic effects on the biodegradation of the fuels in soil and water matrices. Furthermore, results suggest that, in soil, butanol better enhanced the biodegradation of gasoline than ethanol.     

A multicriteria comparison of utilizing sugar cane bagasse for methanol to gasoline and butanol production

The present study makes a consistent and comparative assessment of the overall exergy, financial and environmental efficiencies of two biomass-to-fuels (utilised in internal combustion engines with spark ignition) conversion options and based on this result, gives a recommendation as to which of the options assessed is most desirable. These options are methanol to gasoline (MTG) and biochemical butanol, while as feedstock the solid residue of sugar cane, bagasse, was considered. For the work presented in this study, a base case scenario has first been developed for each pathway by employing either Aspen Plus or SuperPro Designer (as simulators) to perform mass and energy balance calculations while Matlab software has been used for modelling the reaction kinetics of each process. Based on the simulations, thermodynamic (exergy analysis), economic (financial and risk analysis) and environmental (CO₂ emissions) evaluations were carried out. Afterwards, sensitivity analyses have been performed in order to define the key parameters of each conversion route. Exergy and economic analysis favour the gasoline production while butanol produces less CO₂ emissions. The study concludes with multicriteria decision analysis (MCDA) where each process is issued a score according to the investigated criteria. This makes it possible for the investigated procedures to be compared on the same basis. According to this analysis, the production of gasoline achieves a higher overall score than butanol production, i.e. 97% and 90% respectively.     

丁辛醇缩合废水处理技术研究

针对丁辛醇缩合废水进行了实验室探索实验,提出了对该废水进行酸化-萃取-中和-生化处理的工艺,确定了该工艺的处理效果。该处理工艺结合企业实际,克服了目前同类装置存在的不足,技术合理、经济可行。随着该工程的实施,将解决困扰企业多年的丁辛醇高浓度废水的污染问题。     

Effects of pH and ferrous iron on the coproduction of butanol and hydrogen by Clostridium beijerinckii IB4

Butanol and hydrogen gas are main products in butanol production by solventogenic Clostridia. Effects of pH and ferrous iron on hydrogen and butanol production by Clostridium beijerinckii IB4 were investigated in this work. With the increasing of the pH value, the hydrogen yields increased during acidogenic phase and decreased during solventogenic phase. Compared with the process without pH control, butanol and hydrogen increased by 15.43% and 11.77%, respectively, when pH was controlled at 5.2. Under the control of pH at 5.2 and supplementation of 250 mg/L of FeSO₄·7H₂O, the maximum hydrogen quantity of 8.24 L/L was obtained, and hydrogen productivity achieved 187 mL/L/h with yield of 145 mL/g glucose, which increased by 65%, 46% and 37%, respectively. However, butanol yield was reduced slightly by 4.8%. The reducing power was enhanced in solventogenic phase with supplementation of 250 mg/L FeSO₄·7H₂O, and the energy content of fuel produced in this process also remained stable. These results indicated that hydrogen production was enhanced by pH control and ferrous iron regulation, and butanol production performance was also maintained, which was favorable for coproduction of butanol and hydrogen in ABE fermentation.     

Study of the Involvement of Phosphatidic Acid Formation in the Expression of Wound‐Responsive Genes in Cotton

Plants use phospholipase D (PLD, EC 3.1.4.4)/phosphatidic acid (PtdOH) for the transduction of environmental signals including those coming from wounding. Based on our previous findings suggesting that wound‐induced PLDα‐derived PtdOH can act as a local signaling molecule in cotton (Gossypium hirsutum), we show that wounding immediately increases local NADPH oxidase (NADPHox) and cellulose synthase A (CeSA) gene expression. After developing a novel fluorimetric assay for the investigation of n‐butanol inhibitory effect on PLD activity, we show that only NADPHox gene upregulation is reduced when n‐butanol is applied prior to wounding. This suggests that NADPHox is a possible downstream target of PLD function, while a different CeSA‐involving response system may exist in cotton. Overall, this study provides new knowledge on signal‐transduction mechanisms following wounding of cotton leaves.