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A series of novel amine triphenolate iron complexes were synthesized and characterized using UV, IR, elemental analysis, and high-resolution mass spectrometry. These complexes were applied to the ring-opening polymerization (ROP) of cyclohexene oxide (CHO), demonstrating excellent activity (TOF > 11050 h-1) in the absence of a co-catalyst. In addition, complex C1 maintained the dimer in the presence of the reaction substrate CHO, catalyzing the ring-opening polymerization of CHO to PCHO through bimetallic synergy. Furthermore, a two-component system consisting of iron complexes and TBAB displayed the ability to catalyze the reaction of CHO with CO2, resulting in the formation of cis-cyclic carbonate with high selectivity. Complex C4 exhibited the highest catalytic activity, achieving 80% conversion of CHO at a CHO/C4/TBAB molar ratio of 2000/1/8 and a CO2 pressure of 3 MPa for 16 h at 100 °C, while maintaining >99% selectivity of cis-cyclic carbonates, which demonstrated good conversion and selectivity.
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Organization of Economic Cooperation and Development (OECD) economies are facing a substantial increase in the information and communication technology (ICT) investments in the context of rapid spread of the Coronavirus Disease-2019 (COVID-2019) pandemic and constraints of emissions reduction. However, the mechanism of the impact of ICT investments on carbon dioxide is still unclear. Therefore, by employing the decoupling-factor model and Generalized Divisia Index Method, we explore the decoupling states of ICT investments and emission intensity, and the driving factors of ICT investments' scale, intensity, structure, and efficiency effects on carbon emissions in 20 OECD economies between 2000 and 2018. The results indicate that the number of economies with an ideal state of strong decoupling rose to nine between 2009 and 2018 compared to no economies between 2000 and 2009. The emission intensity of ICT investments contributes to a significant increase of carbon emissions, and the structure and efficiency of ICT investments always restrain the growth of carbon emissions. Significant emissions changes caused by the driving factors are shown in many economies before and after the crisis, reflecting the differences in the strategic choices of ICT investments and the impact on emissions due to the crisis such as the COVID-2019 pandemic. And policy implications for energy and carbon dioxide mitigation strategies in the post-COVID-2019 era are also provided.
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With increasing use of chemical oil displacement agents in tertiary recovery and the application of various demulsifiers for crude oil dehydration, a large amount of aging crude oil containing a high ratio of water is produced, and it is very difficult for processing and utilisation. In this article, we chose aging crude oil samples from a union station in an oilfield in China. Sample composition was analysed to demonstrate that the key of aging crude oil dehydration is the removal of solid impurities. Thus, an efficient method of combining heating and chemical treatments was developed to treat aging crude oil. It includes two steps: The first step is washing of aging crude oil with hot water with sodium dodecylbenzene sulfonate; the second step is chemical demulsification of the above mixture with hydrochloric acid and sodium chloride solution. The result showed that 2.9% of solid impurities and 29.2% of water were removed in the first step; 27.2% of oil, 24.3% of water, and 3.47% of solid impurities in the aging crude oil were recycled in the second step. A total 87.07% of aging crude oil could be solved with this method. The present two-step treatment method can ensure that the dehydration process runs normally and efficiently in the union station, making it a promising method in the recycling of aging crude oil.
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Calefação , Petróleo/análiseRESUMO
A pilot-scale airlift bioreactor (ALBR) system was built and operated continuously for refinery excess sludge (RES) reduction. Combined ALBR and function-enhanced microbes (composed of photosynthetic bacteria and yeast) were integrated into the system. The pilot-scale ALBR was operated for 62 days, and the start-up time was 7 d. Continuous operation showed that the sludge reduction efficiency was more than 56.22%, and the water quality of the effluent was satisfactory. This study focused on investigating the effects of hydraulic retention time (HRT) on the stability of the system and the effect of sludge reduction. Under different HRT conditions of 40, 26.7, 20, and 16 h, the sludge reduction rates reached 56.22%, 73.24%, 74.09%, and 69.64%, respectively. The removal rates of chemical oxygen demand (COD) and total nitrogen (TN) decreased with decreasing HRT, whereas the removal rate of NH4+-N increased. The removal rate of total phosphorus (TP) was approximately 30%. Results indicate that the ALBR and function-enhanced microbe system can reduce sludge and treat sewage simultaneously, and the effluent is up to the national emission standard. Addition of function-enhanced microbes can promote the degradation of petroleum hydrocarbon substances in the sludge, especially alkanes with low carbon numbers. This study suggests that the optimal HRT for the system is 16 h. The total operation cost of the ALBR combined with the function-enhanced microbe system can be reduced by 50% compared with the cost of direct treatment of the RES system.
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Esgotos , Eliminação de Resíduos Líquidos , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Nitrogênio , FósforoRESUMO
Underwater superoleophobic coatings have attracted significant research attention for their excellent oil-repellent properties. However, the major challenge for current coatings is poor performance under harsh conditions, leading to limitations in terms of practical application. In this paper, we present a novel bioinspired poly(vinyl alcohol)/zeolite composite coating that can be fabricated through a facile approach. This composite coating shows outstanding underwater superoleophobicity to various oils, as well as good wax-prevention and self-cleaning performance. Furthermore, the excellent mechanical and chemical stabilities of the coating make it suitable for practical applications in harsh environments. This bioinspired multifunctional composite coating has promising prospects in the petroleum industry.
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This study predicts the probabilities of achieving the carbon dioxide (CO2) emission targets set by the Paris Agreement and the Intended Nationally Determined Contribution (INDC) of the top ten CO2 emitters (TTCE). The TTCE are China, USA, India, Russia, Japan, Germany, South Korea, Iran, Saudi Arabia and Indonesia based on their emission trends over 1991-2015 period. The methods of trend extrapolation and back propagation (BP) neural networks are used in this paper to overcome the weakness of multiple linear regression (MLR) and the assumptions of the environmental Kuznets curve (EKC). The results show that the model performs well and has high predictive accuracy. The volume of the CO2 emissions by the TTCE in 2030 is predicted to increase by 26.5-36.5%, compared with 2005. According to different trends of economic growth, energy consumption, and changes in share of renewable energy, the results show that China, India and Russia will achieve their INDC targets in some scenarios, whereas there will be a shortfall in achieving targets by USA, Japan, Germany, and South Korea. In particular, the carbon reduction situations of Saudi Arabia, Iran and Indonesia are quite severe. Moreover, the results show that there is no common trend that can be used as a suitable benchmark for every country for the implementation of carbon reductions targets of the Paris Agreement and their INDC goals. Finally, there are signs of improvement of the equality of carbon emissions based on the analysis of the Gini coefficient.
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A series of carboxybetaine surfactants, 2-((4-(alkoxy)-3,5-dimethylbenzyl)dimethyl-ammonio)acetate (C n OBCb, where n represents the hydrocarbon chain length of 12, 14, 16 and 18), were synthesized by an efficient and high-yield route for the first time. The surface activities and aggregation behavior of C n OBCb in aqueous solution were investigated by equilibrium surface tension, interfacial tension, steady-state fluorescence, dynamic light scattering (DLS), cryogenic transmission electron microscopy (cryo-TEM) and negative-staining transmission electron microscopy (TEM) measurements. In comparison with conventional N-alkylbetaine surfactants (C n Cb), the C n OBCb species, with a phenyl group introduced in the hydrophobic tail, exhibited excellent surface activities, including lower critical micelle concentration (cmc), lower surface tension and stronger adsorption tendency at an air/water interface. C n OBCb also displayed high efficiency in reducing the toluene/water interfacial tension, with C12OBCb achieving an ultralow interfacial tension (10-3 mN m-1) at concentrations from 0.2 to 1 mmol dm-3. The fluorescence intensity ratio and the scattering intensity in DLS measurements changed remarkably at concentrations around the cmc. Furthermore, the C n OBCb species spontaneously formed vesicles above the cmc in aqueous solution, and the size of the aggregates increased with increasing surfactant concentrations. Flooding experiments showed that C n OBCb could effectively improve oil recovery by 7.85-10.55%.