30 research outputs found
Synthesis of benzimidazole-cyclohexanone derivatives
This work reports the synthesis and characterization of new benzimidazole-cyclohexanone derivatives 3a-d, 4a-d and 5a-d under different reaction conditions. The intermediates and final compounds were purified and their chemical structures were elucidated using 1H-NMR, 13C-NMR and mass spectral data.Keywords: Benzimidazole, Cyclohexanone, NMR, Reaction intermediate
Growth, biomass production and ions accumulation in Atriplex nummularia Lindl grown under abiotic stress
Impact of Deficit Irrigation on Yield and Fruit Quality of Orange Trees (Citrus Sinensis, L. Osbeck, CV. Meski Maltaise) in Southern Tunisia
An experiment on deficit irrigation of orange trees (Citrus sinensis, L. Osbeck, cv. Meski Maltaise) with saline water (1.5 g lâ1) was conducted in the arid region of Medenine, Tunisia. Four irrigation treatments were applied: full irrigation (FI), irrigated at 100% of the crop evapotranspiration; deficit irrigation (DI75) and (DI50), which received respectively 25 and 50% less water than FI; and the farmer's method (FM). Soil water content and salinity were monitored during the orange active period. Yield and fruit quality were measured at harvest and used to analyse water productivity (WP) and net income. Results show a decrease in soil salinity between the spring and winter seasons with maximum values observed for the DI50 treatment. Maximum yield levels were obtained under the FI treatment (26.6 t haâ1). Applying continuous deficit irrigation resulted in 24 and 45% yield reduction respectively for DI75 and DI50, compared to FI. Fruitâquality parameters showed significant differences, with higher levels of total soluble solids for DI50 and better fruit weight for FI and FM. For total water supplies between 415 and 786 mm, WP was in the range 2.9â3.6 kg mâ3, with the highest values observed for the DI50 treatment and the lowest for FM. The soil water balanceâbased irrigation method (FI) generated the greatest net income and the lowest soil salinization. Reduction in water supply produced an equivalent reduction in yield but a much stronger decrease in the economic return: using the DI75 strategy resulted in 25% water saving, 24% reduction in yield and 40% reduction in net income
Technoeconomic assessment of hydrothermal liquefaction oil from lignin with catalytic upgrading for renewable fuel and chemical production
Lignin is a readily available by-product of the Kraft pulping process, and may be processed via hydrothermal liquefaction (HTL) to produce a bio-oil suitable for cofeeding into a petroleum refinery hydrotreatment unit. HTL of lignin is performed in near-critical water and, in addition to the bio-oil, produces an aqueous organic and solid char phase. The aqueous organics are primarily phenolics, which may be converted into valuable coproducts via liquidâliquid extraction and hydrotreatment to benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds. Three technological scenarios were developed: a current technology case, a state-of-the-art research case, and an optimal case based on product targets provided by refiners. For a large Kraft pulp mill (400 metric tons/day of dry lignin), a renewable fuel production of 65â70 million L/year, with capital costs of 0.41â0.44 were estimated. The BTEX coproduct yield ranged from 16.8â18.0 million L/year. An economic analysis of the process revealed that the hydrotreatment steps have the highest installed capital costs, while the liquidâliquid extraction process is the largest operating cost. Based on these results, the minimum selling price (MSP) of the biofuel is between 3.86/gallon, and the MSP of BTEX is between 2.00 per liter. With current technology, coproduction of BTEX does not offset the cost of biofuel production. Improved technology to further lower bio-oil oxygen content and decrease both capital and operating costs are needed to make HTL-based fuels competitive with fossil fuel-based options. This article is categorized under: Energy Research & Innovation > Science and Materials Bioenergy > Economics and Policy Bioenergy > Systems and Infrastructure