In the present study, efficient CO2 capture onto the nanostructured Persian ironwood biomass-derived activated carbon/metal oxides (AC/MOs) composites under different conditions, was developed. The as-synthesized highly porous AC, with the chemical activation method using H3PO4, was modified by the carbonization of a single and a binary mixed-MO for the first time. The optimization process of the synthesized adsorbents was conducted considering the different parameters comprising the application of different ratios of activating agent and activation temperatures, various ratios of metal loading, and the diverse temperature treatments to develop the desired MOs. The results illustrated that besides the development of MOs, the textural properties of ACs were significantly improved. Modified ACs showed a higher capture capacity compared to unmodified ones due to the simultaneous physisorption and chemisorption mechanisms for CO2 adsorption. Among all the sorbents, HP5/Cu3-1 demonstrated the highest CO2 adsorption capacity with 6.78 mmol/g, indicating a 124.5% enhancement in comparison with the unmodified AC (3.02 mmol/g) at 1 bar and 30 degrees C. The synthesized binary mixed oxide, HP5/AlMg8-1, also illustrated the increase of adsorption capacity in comparison with its related single oxides (i.e. HP5/Al5-1 and HP5/Mg8-1). Furthermore, after 10 successive adsorption/desorption runs, the adsorption efficiency of the reused HP5/CuNi3-1 decreased by 2.07%.

This study aims to assess the fraction of the isooctane-ethanol blend which has azeotrope condition. Isooctane was selected as a conventional fuel. Isooctane-ethanol blend with various mixture fractions is given the heat to obtain the distillation temperature curve and the fuel vapor. The blended fraction is varied from 0, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100% v/v ethanol to predict the condition (near) azeotrope fuel blend. Molecular analysis was used to verify the predicted azeotrope mixture of isooctane-ethanol. The results show that the isooctane ethanol blend has an azeotrope mixture at exactly on the ethanol fraction of 41.48% v/v. In this fraction blended, two polar molecules of ethanol induce a nonpolar molecule of isooctane to form a molecular cluster.

Waste jeans, containing cotton and polyester, are among the widely available sources for bioenergy production. In this study, the cotton part of waste jean was used for biogas and ethanol production. The hydrolysis of non-cellulosic part, i.e., polyester, and the pretreatment of cellulosic part was performed by sodium carbonate treatment. The effects of Na2CO3 concentration (0, 0.5, and 1 M) and temperature (50, 100, and 150 degrees C) on the cotton, polyester, and textile structure were investigated. The pretreated textile, with over 90% cellulose, was subjected to anaerobic digestion, enzymatic hydrolysis, and fermentation to produce biogas, sugars, and ethanol, respectively. The maximum methane yields of 328.9 and 361.1 mL/g VS were achieved from pure cotton and jeans after pretreatment with 0.5 M Na2CO3 at 150 degrees C for 120 min, respectively. Using the pretreatment, the highest glucose yields of enzymatic hydrolysis were 88.0% and 81.71% for cotton and textile, respectively, while the corresponding values for untreated samples were 36.9 and 28.0%. The maximum ethanol yields of 69.4% and 59.5% were obtained from cotton and textile, respectively. It was concluded that the pretreatment is promising for the hydrolysis of the synthetic polymer of textile and the improvement of the biodegradability of the cellulosic part with negligible cellulose destruction.

This work shows a study of the reactivity of twelve different types of soot with either NO2 or O-2 under reacting conditions typically present in diesel particulate filters (DPFs). The soot samples were obtained from the combustion of four conventional and alternative fuels (diesel, biodiesel and two paraffinic fuels) in a diesel engine bench operated under three different engine operation modes: a typical urban-driving mode and two variations to this mode to assess the effect of the injection settings. The main objective of the work is to relate the oxidative reactivity of the soot to the nature and the origin of each sample. The possible simultaneous elimination of soot and NOx at typical diesel exhaust conditions is examined, as well. The reactivity tests were performed in a laboratory quartz gas flow reactor, discontinuous for the solid. The soot-NO2 interaction was studied with 200 ppm of NO2 at 500 degrees C and the soot-O-2 interaction was studied with 5% O-2 at 500 degrees C and 600 degrees C. The experimental results were used to determine the time needed for the complete conversion of carbon (t) through the use of the equations of the Shrinking Core Model for solid-gas reactions with decreasing size particle and chemical reaction control. In general, the t values show that the diesel fuel generates a less reactive soot than biodiesel or the alternative paraffinic fuels. In addition, increasing the injection pressure or adding a post-injection to the original injection strategy generates a more reactive soot. These findings point out that there is potential to achieve efficient regeneration processes in DPFs through other fuels than conventional ones and via engine calibration.

Evolution profiles on the formation of the carbon particulate (soot) in vaporized coflow diffusion flames of biodiesel (BD), No. 2 diesel and blended fuel mixtures were obtained. The evolution profiles contain the different stages of soot formation, including soot inception, particle growth and agglomeration, and oxidation. Carbon samples were collected directly from inside the flame's yellow luminous zone along the axial direction at various heights above the burner (HAB) using a well-accepted approach. The studied BD flames were formed using canola methyl ester (CME), cotton methyl ester (COME) and soy methyl ester (SME) in their neat form (B100). The blends consisted of B80 (80% CME/20% No. 2 diesel), B50 (50% CME/50% No. 2 diesel) and B20 (20% CME/80% No. 2 diesel). The evolution profile of the No. 2 diesel flame was compared to the evolution profiles of the neat (B100) BD and blended fuel flames. Soot evolution profiles in the studied vaporized BD and diesel flames are consistent with the general trends of particle formation present during the combustion of diesel and gaseous fuels. That is, particle inception (singlet particles) present in a region at the lower part of the flame followed by particle growth and agglomeration, and the subsequent soot carbonization and oxidation in the upper regions of the flame. However, the soot evolution profiles also show that significant differences exist in the soot morphological properties of the tested BD and blended flames. The presence of irregular-shaped fragments such as the liquid-like droplets or globules at the different stages of soot formation is evident in these oxygenated flames. The irregular-shaped fragments resemble short chain-like aggregates that appear to be formed of fused particles having undefined shapes and boundaries. The irregular-shaped fragments resemble eutectic (solid/liquid) phases manifesting their viscous liquid nature. Some of these irregular-shaped structures contain embedded carbonized inclusions. By a small axial variation of the flame, the fragments are transformed into fully carbonized aggregates that are significantly larger and of complex fractal morphology (multi-branched). From the transmission electron microscopy analysis it can be suggested that the liquid-like droplets or globule structures serve as possible growth pathways for the formation of the fully carbonized aggregates composed of spherical particles in the upper part of the flame. The size and number density of the irregular-shaped fragments in the vaporized BD are much larger than those present in the flame formed from the vaporized diesel. It is also observed that as the percentage of BD is increased in the blended flames, these irregular-shaped structures become more pronounced. The evolution profiles also present other morphological properties of the carbon particulates (particle size and nanostructure) along the flame's axial direction.

To understand the detailed catalytic mechanism of ion-exchanging AAEM species on biochar structure and its specific reactivity during CO2/H2O gasification, the experiments were carried out in a laboratory fixed-bed reactor at 800 degrees C, with two kinds of AAEM-loading methods. The migration and precipitation characteristics of AAEM species was evaluated by ICP-AES, while the transformation of biochar structures were analyzed by FTIR and Raman. The specific reactivity of H2O/CO2 gasification biochar was determined by TGA analysis in Air at 370 degrees C. The results show that the stronger catalytic properties of K and Ca species in H2O atmosphere are obtained than that in CO2. The effect of K is mainly on the formation of O-containing functional groups (e.g. alcohol/phenolic-OH, aldehyde/ester C = O and carboxylic -COO- groups) and the transformation from small ring systems to larger ones, while the catalytic effect of Ca is only to increase the proportion of large aromatic ring structures (>= 6 fused benzene rings). The biochar-CO2 reaction took place mainly at the gas-solid interface of biochar, while biochar-H2O one existed throughout the biochar particle. A better distribution of active sites (i.e. surface K/Ca species and O-containing groups) on biochar surface would result in the high specific reactivity of biochar during gasification.