Petrochemical Synthesis Research Articles

Heterogeneous Catalysts for Petrochemical Synthesis and Oil Refining, 2nd Edition

Heterogeneous catalysts play a crucial role in the petrochemical synthesis and oil refining industries [...]

Systemic metabolic engineering of Enterobacter aerogenes for efficient 2,3-butanediol production

2,3-Butanediol (2,3-BDO) is an important gateway molecule for many chemical derivatives. Currently, microbial production is gradually being recognized as a green and sustainable alternative to petrochemical synthesis, but the titer, yield, and productivity of microbial 2,3-BDO remain suboptimal. Here, we used systemic metabolic engineering strategies to debottleneck the 2,3-BDO production in Enterobacter aerogenes. Firstly, the pyruvate metabolic network was reconstructed by deleting genes for by-product synthesis to improve the flux toward 2,3-BDO synthesis, which resulted in a 90% increase of the product titer. Secondly, the 2,3-BDO productivity of the IAM1183-LPCT/D was increased by 55% due to the heterologous expression of DR1558 which boosted cell resistance to abiotic stress. Thirdly, carbon sources were optimized to further improve the yield of target products. The IAM1183-LPCT/D showed the highest titer of 2,3-BDO from sucrose, 20% higher than that from glucose, and the yield of 2,3-BDO reached 0.49 g/g. Finally, the titer of 2,3-BDO of IAM1183-LPCT/D in a 5-L fermenter reached 22.93 g/L, 85% higher than the wild-type strain, and the titer of by-products except ethanol was very low.Key pointsDeletion of five key genes in E. aerogenes improved 2,3-BDO productionThe titer of 2,3-BDO was increased by 90% by regulating metabolic fluxResponse regulator DR1558 was expressed to increase 2,3-BDO productivityGraphical abstract

ISOLATION OF HIGH PURITY PIPERYLENE

Piperylene is a valuable raw material component for petrochemical synthesis, perfumery and cosmetic products, and is used as a solvent for petroleum products in the production of synthetic rubbers and latexes, and in the paint and varnish industry. Piperylene in the form of a fraction is produced in the production of isoprene by the two-stage dehydrogenation of isopentane, where it is a secondary product of the main synthesis. Isolation of commercial piperylene of high purity will allow the production of a value-added product and expand the sales market. Currently, restrictions on the production of commercial piperylene are associated with the high content of an impurity – cyclopentadiene. Previous studies by the author showed the feasibility of extracting cyclopentadiene at the stage of obtaining the catalyzate of the second stage of isoprene dehydrogenation. Simulation of the technological scheme in the application program showed that, together, the extraction of cyclopentadiene by a chemical method and a change in the technological operating mode makes it possible to isolate piperylene with a content of 99.45 % wt and CPD equal to 0.0046 % wt.

Intensification and techno-economic analysis of a biocatalytic process for coniferol production from ferulic acid: An innovative strategy for lignin valorization

Coniferol, as a natural monolignol, acts as a chemical building block for various high-value compounds. However, the current petrochemical synthesis of coniferol and its limited scalability raise environmental and cost concerns. A biocatalytic method for coniferol production from its natural precursor, ferulic acid, was previously developed using an engineered cell factory that co-expresses carboxylic acid reductase and aldo-keto reductase. The present study focused on investigating the limiting factors of coniferol production and optimizing the process using the design of experiments and fed-batch approaches. By introducing novel parameters, including an inoculum of 0.25 g/L cells and a starting concentration of 5.0 mM ferulic acid, followed by two fed-batch additions of 2.0 mM ferulic acid and 3.7 g/L glycerol, coniferol production was enhanced by a factor of 2 (reaching 1.6 g/L). The scale-up process in a 1 L bioreactor and its intensified technical and economic analysis demonstrated its cost-effectiveness. Considering two different purchase prices for the ferulic acid of $5.0 and $650.0 per kg, the payback time was estimated at 3.3 and 3.2 years, respectively, and the minimal selling price of coniferol to obtain a IRR of 30% was calculated as $4.2 and $5.0 per gram, which is significantly lower than the current market price. In conclusion, the findings illustrate a biocatalytic approach for producing valuable compounds with potential applications in various industries, including cosmetics and pharmaceuticals. Furthermore, this approach contributes to developing sustainable and profitable biorefinery processes, paving the way for future initiatives focused on biocatalytic lignin valorization.

Исследование свойств твердого остатка пиролиза осадков сточных вод

This article presents the results of the thermal processing of sludge from domestic wastewater under laboratory conditions. The pyrolysis process is carried out in a batch reactor with an original design. Gaseous and liquid forms of hydrocarbon compounds, as well as solid carbonaceous residue, were obtained after processing the sludge in a pyrolytic plant. It is established that during pyrolysis of sludge sewage sludge, the output of the process products depends on the heating rate of the raw material. The results of chromatographic, X-ray diffraction, spectroscopic studies of the composition, properties, and structure of pyrolysis products are presented in the following sections. This research project involved the analysis of sludge sediment samples obtained from different locations within the oil and gas field of the West Kazakhstan region. The results of the chemical analysis of the initial sludge (pH of the water extract, cationic-anionic composition, determination of organic matter in the sample) selected from several points of the sludge site are presented. Differential thermal analysis of silt sediments has been carried out. The results of this study demonstrate that the pyrolysis of sludge leads to thermal sterilization and the production of gaseous, liquid, and solid carbonaceous residue, which exhibit potential as fuel sources or raw materials for petrochemical synthesis. In addition, heavy metals (such as mercury and cadmium) can be separated from the carbonaceous residue during pyrolysis. It is proposed to use the solid pyrolysis sludge as a sorbent for the collection of oil and petroleum products, as it is economically and environmentally beneficial.

Recent Progress in Metabolic Engineering of Escherichia coli for the Production of Various C4 and C5-Dicarboxylic Acids.

As an alternative to petrochemical synthesis, well-established industrial microbes, such as Escherichia coli, are employed to produce a wide range of chemicals, including dicarboxylic acids (DCAs), which have significant potential in diverse areas including biodegradable polymers. The demand for biodegradable polymers has been steadily rising, prompting the development of efficient production pathways on four- (C4) and five-carbon (C5) DCAs derived from central carbon metabolism to meet the increased demand via the biosynthesis. In this context, E. coli is utilized to produce these DCAs through various metabolic engineering strategies, including the design or selection of metabolic pathways, pathway optimization, and enhancement of catalytic activity. This review aims to highlight the recent advancements in metabolic engineering techniques for the production of C4 and C5 DCAs in E. coli.

Principles of aerobic oxidation of ethylbenzene to hydroperoxide under the presence of phthalimide catalysts

The article describes a study of basic principles of aerobic liquid-phase oxidation of ethylbenzene to hydroperoxide. According to the research, the use of phthalimide catalysts (N-hydroxyphthalimide and its derivatives) can increase the oxidation rate of this hydrocarbon by 1.5-2 times compared with initiators of different nature. At the same time, high selectivity of target hydroperoxide formation is still present - about 90%. The authors recommend conditions for oxidation of ethylbenzene in the presence of phthalimide catalysts based on experimental data. The results obtained can be used to improve the technology for co-production of propylene oxide and styrene, valuable products of the main chemical and petrochemical synthesis.

Techno-economic analysis and life cycle assessment of industrial production of ammonia via bio-oil conversion

This work assess the economic feasibility and environmental burdens of ammonia generation via distributed bio-oil production from corn stover and a central bio-oil reforming pathway or a central bio-oil partial oxidation pathway. The total capital investment is $1,254, 702, 937 for the reforming pathway and $1,273, 047, 866 for the partial oxidation pathway, respectively. The minimum selling price is separately $0.992/kg ammonia for the reforming pathway and $1.05/kg ammonia for the partial oxidation pathway, assuming a standard discount rate of 10%. A sensitivity and optimal analysis shows that the optimal minimum selling price could be as low as $0.39/kg ammonia for the steam-reforming pathway. Global warming potential is 1.11 kgCO2-eq/kg ammonia for the steam-reforming pathway and 1.66 kgCO2-eq/kg ammonia for the partial oxidation pathway, respectively. In this life cycle assessment study, other two categories including eco-indicator 99 and cumulative energy demand were also considered. Finally, the cost for buying or utilizing 1 MJ of biohydrogen contained in ammonia carrier is only 2% of that for buying or utilizing 1 MJ of biohydrogen stored in high pressure tanks. Overall, ammonia production via bio-oil conversion, especially bio-oil steam-reforming, could be more environmental-friendly than ammonia production via petrochemical synthesis, suggesting the economically attractive process in the near future.

New Insights into the Physiology of the Propionate Producers Anaerotignum propionicum and Anaerotignum neopropionicum (Formerly Clostridium propionicum and Clostridium neopropionicum)

Propionate is an important platform chemical that is available through petrochemical synthesis. Bacterial propionate formation is considered an alternative, as bacteria can convert waste substrates into valuable products. In this regard, research primarily focused on propionibacteria due to high propionate titers achieved from different substrates. Whether other bacteria could also be attractive producers is unclear, mostly because little is known about these strains. Therefore, two thus far less researched strains, Anaerotignum propionicum and Anaerotignum neopropionicum, were investigated with regard to their morphologic and metabolic features. Microscopic analyses revealed a negative Gram reaction despite a Gram-positive cell wall as well as surface layers for both strains. Furthermore, growth, product profiles, and the potential for propionate formation from sustainable substrates, i.e., ethanol or lignocellulosic sugars, were assessed. Results showed that both strains can oxidize ethanol to different extents. While A. propionicum only partially used ethanol, A. neopropionicum converted 28.3 mM ethanol to 16.4 mM propionate. Additionally, the ability of A. neopropionicum to produce propionate from lignocellulose-derived substrates was analyzed, leading to propionate concentrations of up to 14.5 mM. Overall, this work provides new insights into the physiology of the Anaerotignum strains, which can be used to develop effective propionate producer strains.

Modelling, design and kinetics of novel Fred-Ugi environmental wastes converter reactor plant for crude oil distillates, minerals and petrochemical synthesis

Modelling, design and kinetics of novel Fred-Ugi environmental wastes converter reactor plant for crude oil distillates, minerals and petrochemical synthesis

Modelling, design and kinetics of novel Fred-Ugi environmental wastes converter reactor plant for crude oil distillates, minerals and petrochemical synthesis

Modelling, design and kinetics of novel Fred-Ugi environmental wastes converter reactor plant for crude oil distillates, minerals and petrochemical synthesis

Development of individual approaches to the use of the gasoline fraction as a raw material for the process of hydrocatalytic isomerization

High-quality processing of petroleum feedstock and gas condensates from the Zhanazhol field will satisfy the demand for high-quality motor and boiler fuel, lubricating oils, petroleum coke, petrochemical synthesis raw materials. Satisfaction of the needs of various industrial sectors and the population in high-quality raw materials requires the development of petrochemical production that approaches European standards. The main consumers are cars and trucks, railway and water transport, as well as various power generators, military and agricultural equipment. In addition to the demand in the products themselves, the demand for fuel quality is also growing, which must not only meet the stringent requirements of world standards, but also have the quality characteristics of raw materials that satisfy the content of sulfur, polycyclic aromatic hydrocarbons, as well as possess a number of low-temperature properties. The purpose of the research is to develop individual approaches to the use of gasoline fractions of oil from the Zhanazhol field as a raw material for the process of hydrocatalytic isomerization, as well as the use of an isomerized product as a component for obtaining clean ecological commercial gasoline. Composition, indicating the potential content of petroleum products and various impurities. As well as a method for describing the technological process of catalytic reforming or hydrocatalytic isomerization of gasoline fractions of oil. The study of the Zhanazhol oil and gas condensate field established specific features of the physicochemical properties of oil with a high content of hydrogen sulfide and carbon dioxide, paraffin hydrocarbons, and the transformation of n-alkanes of the gasoline fraction. Special systems for the collection and treatment of oil, gas, water, and installations for sulfur decanting in a corrosion-resistant state were formed based on the chemical properties of this raw material. The effectiveness of the use of catalytic reforming, under the best conditions of the process, aimed at obtaining low-solidification fuels of petroleum feedstock, has been proven. The use of aluminum-platinum catalysts from high-temperature to low-temperature isomerization is characterized. The optimal technological parameters for the use of catalytic systems have been determined. The practical significance of the research lies in the fact that during the hydrocatalytic isomerization of raw materials with a significant sulfur content, the catalyst quickly becomes intoxicated, so it is advisable to subject it to hydrotreatment, which increases the technical and economic performance of the processing unit. Efficient catalytic systems have been selected that carry out the process of isomerization of the pentane-hexane fraction under various temperature conditions. The optimal technological parameters of their use were determined. The research results can be used to calculate the mass and energy balance of the catalyst regeneration process.

Engineering Escherichia coli for Efficient Aerobic Conversion of Glucose to Malic Acid through the Modified Oxidative TCA Cycle

Malic acid is a versatile building-block chemical that can serve as a precursor of numerous valuable products, including food additives, pharmaceuticals, and biodegradable plastics. Despite the present petrochemical synthesis, malic acid, being an intermediate of the TCA cycle of a variety of living organisms, can also be produced from renewable carbon sources using wild-type and engineered microbial strains. In the current study, Escherichia coli was engineered for efficient aerobic conversion of glucose to malic acid through the modified oxidative TCA cycle resembling that of myco- and cyanobacteria and implying channelling of 2-ketoglutarate towards succinic acid via succinate semialdehyde formation. The formation of succinate semialdehyde was enabled in the core strain MAL 0 (∆ackA-pta, ∆poxB, ∆ldhA, ∆adhE, ∆ptsG, PL-glk, Ptac-galP, ∆aceBAK, ∆glcB) by the expression of Mycobacterium tuberculosis kgd gene. The secretion of malic acid by the strain was ensured, resulting from the deletion of the mdh, maeA, maeB, and mqo genes. The Bacillus subtilis pycA gene was expressed in the strain to allow pyruvate to oxaloacetate conversion. The corresponding recombinant was able to synthesise malic acid from glucose aerobically with a yield of 0.65 mol/mol. The yield was improved by the derepression in the strain of the electron transfer chain and succinate dehydrogenase due to the enforcement of ATP hydrolysis and reached 0.94 mol/mol, amounting to 94% of the theoretical maximum. The implemented strategy offers the potential for the development of highly efficient strains and processes of bio-based malic acid production.

Production of propionate using metabolically engineered strains of Clostridium saccharoperbutylacetonicum

The carboxylic acid propionate is a valuable platform chemical with applications in various fields. The biological production of this acid has become of great interest as it can be considered a sustainable alternative to petrochemical synthesis. In this work, Clostridium saccharoperbutylacetonicum was metabolically engineered to produce propionate via the acrylate pathway. In total, the established synthetic pathway comprised eight genes encoding the enzymes catalyzing the conversion of pyruvate to propionate. These included the propionate CoA-transferase, the lactoyl-CoA dehydratase, and the acryloyl-CoA reductase from Anaerotignum neopropionicum as well as a D-lactate dehydrogenase from Leuconostoc mesenteroides subsp. mesenteroides. Due to difficulties in assembling all genes on one plasmid under the control of standard promoters, the PtcdB-tcdR promoter system from Clostridium difficile was integrated into a two-plasmid system carrying the acrylate pathway genes. Several promoters were analyzed for their activity in C. saccharoperbutylacetonicum using the fluorescence-activating and absorption-shifting tag (FAST) as a fluorescent reporter to identify suitable candidates to drive tcdR expression. After selecting the lactose-inducible PbgaL promoter, engineered C. saccharoperbutylacetonicum strains produced 0.7 mM propionate upon induction of gene expression. The low productivity was suspected to be a consequence of a metabolic imbalance leading to acryloyl-CoA accumulation in the cells. To even out the proposed imbalance, the propionate-synthesis operons were rearranged, thereby increasing the propionate concentration by almost four-fold. This study is the first one to report recombinant propionate production using a clostridial host strain that has opened a new path towards bio-based propionate to be improved further in subsequent work.Key points• Determination of promoter activities in C. saccharoperbutylacetonicum using FAST.• Implementation of propionate production in C. saccharoperbutylacetonicum.• Elevation of propionate production by 375% to a concentration of 3 mM.

INFLUENCE OF ORGANIC MODIFYING ADDITIVES ON QUALITATIVE INDICATORS OF PEAT ACTIVATED COAL

The Institute of Nature Management of the National Academy of Sciences of Belarus conducted extensive research on the production of activated carbons for various purposes from peat, which showed that in order to obtain highquality coals, it is necessary to use high-moor peat of a high degree of decomposition. In order to expand the resource base, it was of interest to explore the possibility of obtaining coal from peat with a lower degree of decomposition.
 Peat samples modified by products and residual products of oil refining and hardwood sawdust in granular form
 were obtained. An assessment of the physico-technical and sorption properties of the obtained granules was carried out.
 The compositions of peat with hydrocarbon additives were also studied by thermal analysis.
 Activated carbons based on compositions of peat, sawdust and some hydrocarbon wastes of petrochemical synthesis have been obtained, and their sorption and strength properties have been studied. It has been established that the use of hydrocarbon modifiers makes it possible to increase the adsorption activity of coals by 20–50 %. The introduction of sawdust into peat also increases the adsorption activity by 13–55 %, depending on the amount of additive introduced, while the strength properties and bulk density decrease in comparison with peat activated carbon.

Complex processing of natural phosphorites using alkaline wastes of petrochemical synthesis and gas sulfur

Complex processing of natural phosphorites using alkaline wastes of petrochemical synthesis and gas sulfur

Liquid-phase hydrogenation of butyl aldehyde promoted on skeletal nickel catalysts

The processes of heterogeneous catalytic hydrogenation of carbonyl-containing compounds into the corresponding alcohols mostly occur under rather harsh conditions; therefore, catalysts and optimal parameters that facilitate the process under mild conditions need to be selected. New ways of synthesizing catalytic systems and the use of harmless, environmentally friendly supercritical liquids as solvents are some of the key areas of green chemistry. At present, due to their high activity, two-component skeletal Ni catalysts are widely used in industry. This work attempts to develop highly efficient catalytic systems based on a three-component alloyed Ni catalyst containing metals (Ru, Rh) for the liquid-phase hydrogenation of aldehydes to butyl alcohols. The physicochemical and catalytic properties of modified alloyed Ni catalysts in the reaction of liquid-phase hydrogenation of butyl aldehyde to butyl alcohol have been investigated. Butyl aldehyde hydrogenation was carried out on a skeletal Ni catalyst promoted with ruthenium or rhodium in water at a temperature of 20–25 °C and the hydrogen pressure of 0.1 MPa. It was found that modified catalysts with high activity and selectivity reduce butyl aldehydes to butyl alcohols. The processes of catalyst preparation and butyl aldehyde hydrogenation are scalable and can be used in various processes of organic and petrochemical synthesis.

Optimization of Carotenoids Production from Camelina sativa Meal Hydrolysate by Rhodosporidium toruloides

Several compounds on the market derive from petrochemical synthesis, and carotenoids are no exception. Nonetheless, since their applications in the food, feed and cosmetic sectors, and because of sustainability issues, carotenoids of natural origin are desirable. Carotenoids can be extracted from several plants but also from carotenogenic microorganisms, among which are yeasts. Nonetheless, to meet sustainability criteria, the substrate used for yeast cultivation has to be formulated from residual biomasses. For these reasons, we deploy the yeast, Rhodosporidium toruloides, to obtain carotenoids from Camelina sativa meal, an underrated lignocellulosic biomass. Its enzymatic hydrolysis ensures the release of the sugars, as well as of the other nutrients necessary to sustain the process. We therefore separately optimized enzymatic and biomass loadings, and calculated the yields and productivities of the obtained carotenoids. The best conditions (9% w/v biomass, 0.56% w/wbiomass enzymes) were tested in different settings, in which the fermentation was performed separately or simultaneously with hydrolysis, resulting in a similar production of carotenoids. In order to collect quantitative data under controlled chemo-physical parameters, the process was implemented in stirred-tank bioreactors, obtaining 3.6 ± 0.69 mg/L of carotenoids; despite the volumetric and geometric change, the outcomes were consistent with results from the fermentation of shake flasks. Therefore, these data pave the way to evaluate a potential future industrialization of this bioprocess, considering the opportunity to optimize the use of different amounts of biomass and enzyme loading, as well as the robustness of the process in the bioreactor.

Heterogeneous Catalysts for Petrochemical Synthesis and Oil Refining

In modern industry, more than 90% of processes are catalytic [...]

L-Carnitine Production Through Biosensor-Guided Construction of the Neurospora crassa Biosynthesis Pathway in Escherichia coli.

L-Carnitine is a bioactive compound derived from L-lysine and S-adenosyl-L-methionine, which is closely associated with the transport of long-chain fatty acids in the intermediary metabolism of eukaryotes and sought after in the pharmaceutical, food, and feed industries. The L-carnitine biosynthesis pathway has not been observed in prokaryotes, and the use of eukaryotic microorganisms as natural L-carnitine producers lacks economic viability due to complex cultivation and low titers. While biotransformation processes based on petrochemical achiral precursors have been described for bacterial hosts, fermentative de novo synthesis has not been established although it holds the potential for a sustainable and economical one-pot process using renewable feedstocks. This study describes the metabolic engineering of Escherichia coli for L-carnitine production. L-carnitine biosynthesis enzymes from the fungus Neurospora crassa that were functionally active in E. coli were identified and applied individually or in cascades to assemble and optimize a four-step L-carnitine biosynthesis pathway in this host. Pathway performance was monitored by a transcription factor-based L-carnitine biosensor. The engineered E. coli strain produced L-carnitine from supplemented L-Nε-trimethyllysine in a whole cell biotransformation, resulting in 15.9 μM carnitine found in the supernatant. Notably, this strain also produced 1.7 μM L-carnitine de novo from glycerol and ammonium as carbon and nitrogen sources through endogenous Nε-trimethyllysine. This work provides a proof of concept for the de novo L-carnitine production in E. coli, which does not depend on petrochemical synthesis of achiral precursors, but makes use of renewable feedstocks instead. To the best of our knowledge, this is the first description of L-carnitine de novo synthesis using an engineered bacterium.