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Alkenes are among the most versatile building blocks and are widely used for the production of polymers, detergents and synthetic lubricants. Currently, alkenes are sourced from petroleum feedstocks such as naphtha. In light of the necessity to invent sustainable production methods, multiple approaches to making alkenes from abundant fatty acids have been evaluated. However, all attempts so far have required at least one stoichiometric additive, which is an obstruction for applications at larger scales. Here, we report an approach to making olefins from carboxylic acids, in which every additional reaction constituent can be used as a catalyst. We show how abundant fatty acids can be converted to alpha-olefins, and expand the method to include structurally complex carboxylic acids, giving access to synthetically versatile intermediates. Our approach is enabled by the cooperative interplay between a cobalt catalyst, which functions as a proton reduction catalyst, and a photoredox catalyst, which mediates oxidative decarboxylation; coupling both processes enables catalytic conversion of carboxylic acids to olefins.

Although olefin aromatization reactions offer a potential route for the high-value utilization of Fischer–Tropsch naphtha, their industrial implementation is hindered by challenges such as coke-induced deactivation and the formation of large amounts of low-value alkane by-products. In this work, a series of Ga(x%)-EATP-550 catalysts were prepared via equal-volume impregnation of Ga onto an acid-etched attapulgite (EATP) support, followed by calcination at 550 °C. The catalysts were evaluated for the aromatization of olefins. The results show that the reaction proceeds mainly through direct dehydrogenative aromatization, yielding approximately 65% aromatics, while generating short-chain olefins (about 20% yield) as the main by-products. This system effectively suppresses the formation of long-chain aromatics and low-value alkanes, presenting a promising technical pathway for upgrading Fischer–Tropsch naphtha.

The Pc21 g14570 gene of Penicillium chrysogenum encodes an ortholog of a class 2 histone deacetylase termed HdaA which may play a role in epigenetic regulation of secondary metabolism. Deletion of the hdaA gene induces a significant pleiotropic effect on the expression of a set of polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS)‐encoding genes. The deletion mutant exhibits a decreased conidial pigmentation that is related to a reduced expression of the PKS gene Pc21 g16000 (pks17) responsible for the production of the pigment precursor naphtha‐γ‐pyrone. Moreover, the hdaA deletion caused decreased levels of the yellow pigment chrysogine that is associated with the downregulation of the NRPS‐encoding gene Pc21 g12630 and associated biosynthetic gene cluster. In contrast, transcriptional activation of the sorbicillinoids biosynthetic gene cluster occurred concomitantly with the overproduction of associated compounds . A new compound was detected in the deletion strain that was observed only under conditions of sorbicillinoids production, suggesting crosstalk between biosynthetic gene clusters. Our present results show that an epigenomic approach can be successfully applied for the activation of secondary metabolism in industrial strains of P. chrysogenum. Deletion of the histone deacetylase gene hdaA of Penicillium chrysogenum induces a pleiotropic effect on secondary metabolism. The hdaA deletion results in the transcriptional activation of the sorbicillinoids biosynthetic gene cluster. Sorbicilloids cause repression of a series of secondary metabolism genes.

The conventional pesticide emulsifiable concentrate (EC) formulations usually contain a large amount of aromatic solvents. This causes adverse effects to environment and human health due to the toxicity of such organic solvents. In this study, a cypermethrine 25EC formulation was developed using methyl ester as a green solvent. The physicochemical characterizations, emulsion properties and storage stabilities of the methyl ester EC formulations were investigated and compared with those of the EC formulation using naphtha A100 as a solvent, evidencing excellent emulsion properties and storage stabilities of such methyl ester EC formulations.

In this study, an artificial neural network (ANN) model was developed and compared with a rigorous mathematical model (RMM) to estimate the performance of an industrial heavy naphtha reforming process. The ANN model, represented by a multilayer feed forward neural network (MFFNN), had (36-10-10-10-34) topology, while the RMM involved solving 34 ordinary differential equations (ODEs) (32 mass balance, 1 heat balance and 1 momentum balance) to predict compositions, temperature, and pressure distributions within the reforming process. All computations and predictions were performed using MATLAB® software version 2015a. The ANN topology had minimum MSE when the number of hidden layers, number of neurons in the hidden layer, and the number of training epochs were 3, 10, and 100,000, respectively. Extensive error analysis between the experimental data and the predicted values were conducted using the following error functions: coefficient of determination (R2), mean absolute error (MAE), mean relative error (MRE), and mean square error (MSE). The results revealed that the ANN (R2 = 0.9403, MAE = 0.0062) simulated the industrial heavy naphtha reforming process slightly better than the rigorous mathematical model (R2 = 0.9318, MAE = 0.007). Moreover, the computational time was obviously reduced from 120 s for the RMM to 18.3 s for the ANN. However, one disadvantage of the ANN model is that it cannot be used to predict the process performance in the internal points of reactors, while the RMM predicted the internal temperatures, pressures and weight fractions very well.

Heavy organic liquids are typically used for coal laboratory float and sink testing. Perchloroethylene (PCE), methylene bromide and naphtha are typical liquids used in labs worldwide to create baths with a wide range of specific gravities. All three of these liquids are harmful to human health and can have negative effects on coal rheology. Perchloroethylene is a solvent that has been used to remove organic sulfur from coal prior to use in power generation plants. The PCE acts as a swelling agent and when heated in the presence of a catalyst, will cleave the C-S bonds, removing organic sulfur from the coal. PCE is a clear liquid however after the float and sink process it turns shades of yellow to dark brown. Portions of the coal become suspended in solution and many organically bound elements are released from the coal into the solution. This may result in certain elements being underestimated in the clean coal products arising from perchloroethylene based float and sink. The float and sink test assesses metallurgical coal washability using organic liquids, but traditional options like naphtha, perchloroethylene, and methylene bromide pose health risks. This study examines the effects of four liquids on coal quality and chemistry.

Extraction of low concentration linear alkanes (C 5 -C 7 ) from various isomers is critical for the petrochemical industry. At present, the separation of alkane isomers is mainly accomplished by distillation, which results in substantial energy expenditure. Metal-organic frameworks (MOFs) with well-tailored nanopores have been demonstrated to be capable of realizing molecule-level separation. In this study, oriented HKUST-1 membranes are formulated according to the morphology-biased principle and finally realized with a low dose synthesis method for terminating undesired crystal nucleation and growth. The fully exposed triangular sieving pore array of the membrane induces configuration entropic diffusion to split linear alkanes from mono-branched and di-branched isomers as well as their cyclical counterparts. Typically, the current separation technique consumes 91% less energy than vacuum distillation. Furthermore, our membranes can realize one-step extraction of normal- pentane, normal- hexane and normal- heptane from a ten-component alkane isomer solution that mimics light naphtha. Extraction of linear alkanes from various isomers is critical for the petrochemical industry. Here authors present an oriented MOF membrane with a rigid triangular pore array for one-step extraction of linear pentane, hexane, and heptane from a ten-component alkane isomer solution.

Recently, the isomerization of light naphtha has been increasingly significant in assisting refiners in meeting sternness specifications for gasoline. Isomerization process provides refiners with the advantage of reducing sulfur, olefin, and benzene in the gasoline basin without significantly victimizing the octane. The mathematical modeling of a chemical reaction is a critical tool due to it can used to optimize the experimental data to estimate the optimum operating conditions for industrial reactors. This paper describes light naphtha isomerization reactions over a Pt/Al2O3-Cl catalyst at the Al-Dura Oil Refinery (Baghdad, Iraq) using a newly developed universal mathematical model. The proposed kinetic model involves 117 isomerization reactions and 90 cracking reactions to describe 52 real components graded from methane to n-octane. A Genetic Algorithm stochastic optimization technique applied in MATLAB R2020a software was employed to estimate the optimal set of kinetic parameters. The calculated activation energies for hydrocracking reactions was found to be higher than the other reactions because of hydrocracking reactions occur at higher range of temperatures. By benchmarking between the experimental and theoretical results for all 117 data sets, the mean absolute error was obtained to be 0.00360 for all 52 components. Also, a positive effect of increasing reaction temperatures was recognized on enhancing the research octane number (RON).

Development of versatile ruthenium olefin-metathesis catalysts with high activity, stability, and selectivity is a continuous challenge. Here we report highly controllable ruthenium catalysts using readily accessible and versatile N -vinylsulfonamides as carbene precursors. Catalyst initiation rates were controlled in a straightforward manner, from latent to fast initiating, through the facile modulation of the N -vinylsulfonamide ligands. Trifluoromethanesulfonamide-based catalysts initiated ultrarapidly even at temperatures as low as −60 °C and continuously propagated rapidly, enabling the enthalpically and entropically less-favored ring-opening metathesis polymerizations of low-strained functionalized cyclopentene derivatives, some of which are not accessible with previous olefin-metathesis catalysts. To our surprise, the developed catalysts facilitated the polymerization of cyclopentadiene (CPD), a feedstock that is easily and commonly obtainable through the steam cracking of naphtha, which has, to the best of our knowledge, not been previously achieved due to its low ring strain and facile dimerization even at low temperatures (below 0 °C). Due to the low ring strain and facile dimerization, ring-opening metathesis polymerization of cyclopentadiene, readily obtainable from petroleum feedstock, has not been realized. Here the authors show an ultrarapidly initiating trifluoromethanesulfonamide-based ruthenium catalyst enables it at low temperatures.