69 results about "Mole fraction" patented technology

The invention discloses a short c-axis flaky mordenite molecular sieve as well as a preparation method and application thereof, and belongs to the technical field of molecular sieves. The chemical composition of the short c-axis flaky mordenite molecular sieve is Ra.Mb. (SixAly) O2, r is a template agent tetraethylammonium ion; a is the mole number of R in each mole of (SixAly) O2, and a is more than or equal to 0.02 and less than or equal to 0.04; m is an alkali metal ion; b is the mole number of M in each mole of (SixAly) O2, and b is more than or equal to 0.02 and less than or equal to 0.06; x is the mole fraction of Si in each mole of (SixAly) O2, and x is more than or equal to 0.9 and less than or equal to 0.97; y is the mole fraction of Al in each mole of (SixAly) O2, y is more than or equal to 0.03 and less than or equal to 0.1, and x + y is equal to 1; and the dimension thickness of the stone molecular sieve in the c-axis direction is 20-80 nanometers. The molecular sieve shows excellent catalytic performance in a catalytic reaction for preparing methyl acetate through dimethyl ether carbonylation.

The invention discloses a pretreatment system and an automatic measuring method suitable for measuring the mole fraction of carbon dioxide in a water body through a water-gas balance method, and relates to the field of gas analysis and measurement, the pretreatment system comprises an automatic condensation water removal system, a gas valve automatic switching system, a control system and PC end upper computer software; the automatic condensation water removal system adopts a semiconductor condenser and a Nafion drying pipe to remove water; the gas valve automatic switching system automatically switches standard gas and balance gas through a valve; the control system is connected with the gas valve automatic switching system and PC end upper computer software, monitors and adjusts the gas flow rate in real time, and ensures that the gas flow rate is within a preset range; the upper computer software of the PC end integrates data processing and visualization functions, and automatic control and real-time data recording and analysis of the whole system are achieved. The system is reasonable and simple in structure, easy to carry and install, easy and convenient to use, stable in operation and capable of visually displaying the change trend of the CO2 mole fraction in a research area in real time.

Described is a computer-implemented method for modeling an equilibrium separation in a chemical separator. The method can include representing a feedstock of the chemical separator as a collection of molecules, each molecule having a mole fraction. A cluster analysis is performed on the feedstock based on a property of the collection of molecules to generate thermodynamic lumps. A mapping identity table is generated that identifies each molecule of the collection of molecules in the feedstock. A simulation of a chemical separation of the thermodynamic lumps is performed. The mole fraction of molecules in a resultant first phase and the mole fraction of molecules in a resultant second phase is determined.

The invention relates to the technical field of oxygen-enriched combustion safety and flammability limit prediction, and provides a flammability limit value prediction method and application, and the method comprises the steps: obtaining the initial parameters of a gas fuel in a mixed atmosphere of oxygen and carbon dioxide; simulating a combustion process by using an element reaction mechanism, and outputting a curve of component mole fractions changing along with time; the combustion enthalpy change rate under the target atmosphere and the virtual atmosphere is calculated based on the curve, and carbon dioxide in the virtual atmosphere is replaced with virtual gas which has the same thermophysical property but does not have chemical reactivity; respectively calculating combustion heat release, mixture heat absorption and heat radiation; and in combination with the enthalpy change rate and the energy balance equation, the combustible limit value is solved and determined through numerical iteration. By quantifying the chemical effect and thermophysical influence of carbon dioxide, the problem of insufficient precision caused by neglecting the participation of carbon dioxide in reaction and unique thermal property in the oxygen-enriched combustion environment in the existing model is solved, and the method is suitable for the safety design of a combustion system.

The invention relates to a method for calculating viscosity of multi-component fluid in tight reservoir space, and belongs to the technical field of unconventional oil and gas reservoir development. The invention discloses a method for calculating viscosity of a multi-component fluid in a tight reservoir space. The method comprises the following steps: acquiring pore parameters in nanopores of a tight reservoir, components of the fluid and basic parameters of the components; constructing a two-phase flash evaporation calculation model coupled with the nanopore confinement effect; calculating a fugacity coefficient, a component equilibrium constant and the mole fraction of an equilibrium phase component in a gas-liquid phase according to the constructed two-phase flash calculation model coupled with the nanopore confinement effect; and calculating the fluid viscosity in the tight reservoir space when the nano confinement effect is considered according to the mole fraction of each component in combination with a phase equilibrium calculation model. According to the method, the flowing behavior of the fluid in the tight reservoir can be predicted more accurately, the mining scheme is optimized, and the mining efficiency is improved.

The invention provides a Raman analysis method of mixed gas content and an ethylene cracking gas detection method and system, and belongs to the technical field of gas mixture online detection.The analysis method comprises the steps that mixed gas is split into n key components, and reference components are determined; performing spectral signal processing on the original Raman spectrum to obtain a normalized spectrum, and determining the relative Raman peak heights of the n key components; based on the relative Raman peak heights and the regression coefficients of the n-1 key components, determining the molar ratios of the n-1 key components relative to the reference component; the molar fractions of the n key components are determined based on the molar ratios of the n-1 key components relative to the reference component. The detection method comprises the following steps: taking an ethylene independent Raman peak near 1345cm <-1 > as a reference peak, and determining the content of each component of the ethylene cracking gas by adopting the analysis method. According to the method provided by the invention, the complex ethylene cracking gas composition can be accurately and rapidly detected.

The invention relates to the technical field of crystal structure prediction, and discloses a quantum algorithm-based energetic CxNyOz crystal structure prediction method, which comprises the following steps of: calculating an evaporation and diffusion dimensionless number and capillary pressure by obtaining surface tension, a contact angle, a geometric feature scale, temperature, partial pressure, a diffusion coefficient and an evaporation rate; establishing a residual solvent mole fraction and solvent chemical potential sequence; constructing a binary layer occupancy model Hamiltonian containing layer occupancy energy, adjacent layer action energy, a capillary pressure volume term and a molecular polarity action term, and obtaining a hierarchical occupancy number by using a quantum approximation optimization algorithm; calculating interlayer respiration and shear frequency and mode volume sensitivity based on a quantum variation algorithm; and finally, the lattice spacing and the prediction result are obtained through cost functional minimization, and accurate prediction and quantitative analysis of the structure of the energetic crystal under the unbalanced desolvation condition are realized.

The present invention provides a solubility calculation method, a solubility calculation apparatus, and a computer-readable storage medium. The solubility calculation method comprises the following steps: setting initial molar fractions, initial temperatures, and initial pressures of a plurality of components in two phases, i.e., a gas phase and a liquid phase, substance parameters of the components, and binary interaction parameters among the components in an olefin polymerization system, the sum of the initial molar fractions of the components being 1 in both the gas phase and the liquid phase; calculating the fugacities of the components in the two phases, i.e., the gas phase and the liquid phase, and, on the basis of same, setting fugacity-related gas-liquid phase equilibrium conditions; and, in response to the molar fractions of the components satisfying the gas-liquid phase equilibrium conditions, and on the basis of the molar fraction of at least one liquid phase component, solving for the solubility thereof in the olefin polymerization system. The present invention can be used for solving the problem of gas-liquid phase equilibrium of a mixture of a plurality of components, so as to quickly and accurately converge to a phase equilibrium point.

The present application relates to the technical field of oxygen-enriched combustion safety and flammability limit prediction, and provides a flammability limit value prediction method and application, which comprises the following steps: obtaining initial parameters of a gas fuel in an oxygen and carbon dioxide mixed atmosphere; simulating a combustion process by using a base reaction mechanism, and outputting a curve of component mole fraction changing with time; calculating a combustion enthalpy change rate in the target atmosphere and a virtual atmosphere based on the curve, wherein the carbon dioxide in the virtual atmosphere is replaced by a virtual gas with the same thermal properties but without chemical reactivity; respectively calculating a combustion heat release, a mixture heat absorption and a heat radiation; and combining the enthalpy change rate and an energy balance equation to determine the flammability limit value by numerical iteration. The present application quantifies the chemical effect and thermal physical influence of carbon dioxide, solves the problem of insufficient accuracy of existing models in the oxygen-enriched combustion environment due to the neglect of the reaction of carbon dioxide and its unique thermal properties, and is suitable for combustion system safety design.

The invention discloses aluminosilicate green fluorescent powder with an abnormal thermal quenching effect, the chemical formula is Mg2-x-yMxAl4Si5O18: Tby, Tb < 3 + > is taken as a luminescence center, M is Ca < 2 + > or Sr < 2 + >, x / y is molar fraction, x is more than or equal to 0 and less than or equal to 0.5, and y is more than or equal to 0.045 and less than or equal to 0.135. The fluorescent powder emits green fluorescence with a peak value of 543 nm under the excitation of ultraviolet light. When the temperature rises, the luminescent property of the fluorescent powder shows an abnormal thermal quenching phenomenon, and when the temperature is 503K, the emission peak intensity at 543nm is 116% of that at 303K, and the fluorescent powder has excellent thermal stability.

This invention discloses a method, apparatus, equipment, and medium for predicting the dew point pressure of condensate gas. The method includes: inputting basic data of a condensate gas sample and initializing the dew point pressure value; using the 4CM splitting method to split and characterize the C7+ component in the condensate gas; estimating the gas-liquid phase equilibrium constant and the mole fraction of each component in the liquid phase based on the mole fraction of each component after splitting; calculating the gas-liquid phase compressibility factor using the improved equation of state (MPR) based on the gas-liquid phase equilibrium constant, the mole fraction of each component in the liquid phase, and the relevant data after characterization; determining whether the absolute value of the difference between the gas and liquid phase fugacity satisfies the equilibrium condition and whether the sum of the mole fractions of each component in the liquid phase satisfies the preset convergence condition; and finally outputting the calculated dew point pressure. This invention utilizes an integrated and innovative method for thermodynamic model construction, resulting in high accuracy and low calculation error in predicting the dew point pressure of condensate gas.

This invention discloses a method for predicting the solubility of elemental sulfur, comprising the following steps: obtaining parameter information of the target gas and calculating the target gas density ρ; selecting a prediction model based on the target gas temperature T, and determining the model parameters based on the H2S mole fraction and the target gas density ρ: when 373.15K≤T≤433.15K, the prediction model is c=ρ k exp(a / T+b); When 303.15K≤T<373.15K, the prediction model is: where c is the solubility of elemental sulfur in the target gas, k, a, and b are model parameters, model parameter k is a function of T, and the low-temperature correction coefficient d; Based on the selected prediction model and the determined model parameters, the solubility of elemental sulfur in the target gas is calculated. This invention also discloses an elemental sulfur solubility prediction system, electronic equipment, and storage medium. The elemental sulfur solubility prediction method of this invention is applicable to the temperature span in the development process of acidic gas reservoirs, introducing a low-temperature coefficient in the low-temperature range to ensure prediction accuracy throughout the entire temperature range.

The invention discloses an optical temperature measurement luminescent material, the chemical composition general formula of the luminescent material is Sc2-x-yMo3O12: xSm < 3 + >, yEu < 3 + >, x is more than or equal to 0.01 and less than or equal to 0.05, and y is more than or equal to 0.01 and less than or equal to 0.05. A preparation method of an optical temperature measurement luminescent material comprises the following steps: (1) taking an oxygen-containing compound containing elements of Sc, Sm, Mo and Eu as a raw material, weighing corresponding raw materials according to a molar ratio of each element in a chemical composition general formula Sc2-x-yMo3O12: xSm < 3 + > and yEu < 3 + >, x and y being doped molar fractions of Sm < 3 + > and Eu < 3 + >, 0.01 < = x < = 0.05, and 0.01 < = y < = 0.05; (2) fully grinding the weighed raw materials in a mortar, and uniformly mixing to obtain a solid mixture; (3) sintering the solid mixture in an air atmosphere; and (4) cooling the sintered product to room temperature along with the furnace, and grinding with a mortar to obtain Sm < 3 + > and Eu < 3 + > doped Sc2Mo3O12 powder.

The invention belongs to the technical field of ceramic materials, and particularly relates to a high-entropy relaxor ferroelectric ceramic material and a preparation method thereof.The chemical general formula of the high-entropy relaxor ferroelectric ceramic material is (1-x) (Pb0. 25Ba0. 25Sr0. 25Ca0. 25) TiO3-xNaNbO3, x is the mole fraction, x is larger than or equal to 0.1 and smaller than or equal to 0.3, and x is larger than or equal to 0.1 and smaller than or equal to 0.3. The high-entropy relaxor ferroelectric ceramic material disclosed by the invention has relatively high energy storage density, energy storage efficiency, breakdown field energy and stability at the same time.

The application belongs to the technical field of petroleum chemical industry, and discloses a construction method of an atmospheric distillation dynamic hybrid model based on a crude oil molecular model drive. In the calculation of a stable state, the distillation property parameters of the crude oil molecular model related to the molecular pure substance and the distillation process are calculated, and the distillation related property parameters of the mixture are calculated according to the mixing rule; the mechanism model is established for the whole primary distillation column, the top and bottom of the atmospheric distillation column according to the material balance equation, the phase balance equation, the mole fraction normalization equation and the heat balance equation; the agent model is established for the remaining main part of the atmospheric distillation column according to the agent model; and the atmospheric distillation process dynamic hybrid model with the structure of mechanism model-agent model-mechanism model is built in the order of the primary distillation column-atmospheric distillation column main part-atmospheric distillation column top and bottom. The model can simulate and calculate the specific molecular composition distribution of the product.

To provide a radiopaque glass material in the form of microspheres that may be used for vascular embolization and / or radiologic imaging.SOLUTION: A glass material includes: about 0.55 to about 0.85 mole fraction of SiO2; about 0.01 to about 0.23 mole fraction of Na2O, K2O, or a combination of Na2O and K2O; about 0.05 to about 0.28 mole fraction of Y2O3, BaO, or a combination of Y2O3 and BaO; and optionally Ta2O5. In the glass material, the sum of the Y2O3, the BaO, and the optional Ta2O5 is about 0.01 to about 0.31 mole fraction.SELECTED DRAWING: Figure 2D

This invention provides a method for analyzing the impurity content of liquid carbon dioxide in a pressure storage tank, comprising: determining the gas phase mole fraction and thermodynamic parameters of each component in the pressure storage tank before taking out a specific volume of liquid carbon dioxide from the bottom of the tank; calculating the gas-liquid equilibrium constant, mole number, and mole fraction of each component in the pressure storage tank before taking out the liquid; calculating the liquid phase mole fraction of each component in the pressure storage tank before taking out the liquid; calculating the mole fraction of each component in the pressure storage tank after taking out the specific volume of liquid carbon dioxide; and determining the impurity content of the liquid carbon dioxide in the pressure storage tank after taking out the specific volume of liquid carbon dioxide. This invention enables dynamic analysis of the impurity content of liquid carbon dioxide in pressure storage tanks, solving the problems of high difficulty and low accuracy in measuring the composition of impurities in liquid carbon dioxide in pressure storage tanks, and providing a basis for subsequent research on carbon dioxide pipeline transportation technology.

Provided in the present invention is a method for determining the content of a target component in a gas mixture by means of Raman spectroscopy, comprising: performing Raman spectroscopy detection on a gas mixture to obtain a Raman spectrogram; selecting one characteristic peak from the Raman spectrogram as a reference peak, the component corresponding thereto being a reference component, and normalizing characteristic peaks in the Raman spectrogram relative to the reference peak, so as to obtain a relative Raman peak height of each characteristic peak; in combination with the Raman spectrogram of a pure target component, determining the peak position of the characteristic peak of each target component in the Raman spectrogram of the gas mixture; on the basis of the relative Raman peak height of the target component and a regression coefficient obtained on the basis of a training sample set of the gas mixture, determining the molar ratio or volume ratio of the target component to the reference component in the gas mixture; and, on the basis of the molar ratio or volume ratio of the target component to the reference component, determining the molar fraction or volume fraction of each target component in the gas mixture.

A powder for manufacturing wherein the powder contains silicon carbide and boron carbide, wherein the powder includes particles having a particle size of more than or equal to 5 μm and containing silicon carbide, and particles having a particle size of less than or equal to 50 μm and containing boron carbide, and wherein a difference between a mole fraction of the silicon carbide and a mole fraction of the boron carbide in the powder is less than or equal to 60 mol % pt.

The application discloses SAPO-18-MeR molecular sieve and a preparation method and application thereof. The anhydrous chemical composition of the molecular sieve is mMe*nR(Si x Al y P z )O2; Me is at least one selected from Li + , Na + , K + and NH4 + ; R is at least one selected from N, N-diisopropyl ethylamine, tetraethyl ammonium hydroxide, triethylamine, diisopropylamine, diethylamine and ethylenediamine; m is the mole number of Me, m=0.05-0.2; n is the mole number of R, n=0.05-0.2; x is the mole fraction of Si, x=0.05-0.35; y is the mole fraction of Al, y=0.35-0.55; z is the mole fraction of P, z=0.25-0.45, and x+y+z=1. The molecular sieve has excellent silicon distribution and strong acid property, and has excellent catalytic performance as a denitration catalyst after loading Cu ions.

A method for estimating the mole fraction of two components (gas 1 and gas 2) in a gas mixture, components which are neutral gases, the gas mixture being a gas mixture with N constituents (N>2), the method comprising the implementation of the following measures: the mole fraction of constituents 3 to N in the mixture is evaluated by the use of sensors specific to each of these gases implementing commercially available methods on the gas analysis market; the pressure and temperature of the gas mixture are measured; the speed of sound in the gas mixture is measured; and the mole fractions of the two neutral gas components (gas 1 and gas 2) in the mixture are deduced from the previous measurements.

The invention discloses a short c-axis flaky mordenite molecular sieve as well as a preparation method and application thereof, and belongs to the technical field of molecular sieves. The chemical composition of the short c-axis flaky mordenite molecular sieve is Ra.Mb. (SixAly) O2, r is a template agent and is selected from cycloheximine; a is the mole number of R in each mole of (SixAly) O2, and a is more than or equal to 0.02 and less than or equal to 0.04; m is an alkali metal ion; b is the mole number of M in each mole of (SixAly) O2, and b is more than or equal to 0.02 and less than or equal to 0.06; x is the mole fraction of Si in each mole of (SixAly) O2, and x is more than or equal to 0.9 and less than or equal to 0.97; y is the mole fraction of Al in each mole of (SixAly) O2, y is more than or equal to 0.03 and less than or equal to 0.1, and x + y is equal to 1; the dimension thickness of the stone molecular sieve in the c-axis direction is 30-100 nanometers. The molecular sieve shows excellent catalytic performance in a catalytic reaction for preparing methyl acetate through dimethyl ether carbonylation.

The invention discloses a method for measuring and analyzing a material mixing and dispersing heat effect. The method comprises the following steps: adding a backing material and a charging material into a reactor, and mixing; measuring heat flow data of the wall surface of the reactor in the mixing process and calculating first mixing dispersion heat; fitting the calculated first mixed dispersion heat, the mole fraction of the base material in the mixed material and the mole fraction of the added material in the mixed material by adopting a plurality of thermodynamic models, selecting the normalized mean square deviation root deviation of a fitting result, and determining the thermodynamic model of which the coefficient and the absolute average error both meet threshold requirements; calculating a second mixing dispersion heat based on the selected thermodynamic model; and correcting the heat in the reaction process after the materials are mixed by adopting the second mixing dispersion heat. The invention further discloses a measurement and analysis system for implementing the method. The thermal effect in the reaction process is corrected, and the real reliability of monitoring parameters in the chemical reaction process is effectively improved.

This invention discloses a thermochromic luminescent material, its preparation method, and its applications. The general chemical formula of the thermochromic luminescent material is RbCd. (1‑x) Mn x Cl3; x is the mole fraction, with a value ranging from 0 < x ≤ 15%. The thermochromic luminescent material provided by this invention exhibits significant thermochromic luminescence characteristics. At room temperature, RbCd... (1‑x) Mn x Cl3 belongs to the orthorhombic crystal system with space group Pnma. Under ultraviolet light irradiation, it exhibits red light emission. When RbCd... (1‑x) Mn x When Cl3 is heated to above 420K, its crystal structure changes to a tetragonal system with a space group of P4 / mbm, exhibiting yellow light emission. Furthermore, the fluorescence intensity of this thermochromic luminescent material increases with increasing temperature during the temperature variation process from 160K to 420K, demonstrating a significant resistance to thermal quenching. In addition, this invention provides a simple synthesis process with mild reaction conditions, abundant and inexpensive raw materials, solving the problems of lead toxicity and instability in lead-based halide crystals, and is expected to be widely used in intelligent responsive luminescence, anti-counterfeiting, and temperature measurement fields.

The invention discloses a soil organic carbon source and stability rapid evaluation method based on a solid 13C nuclear magnetic resonance spectrum and an intelligent analysis system, and the method comprises the following steps: carrying out standard pretreatment on a soil sample, and detecting the soil sample by using a solid 13C nuclear magnetic resonance technology to obtain spectrum data; partitioning the obtained spectrum data according to a standard chemical shift interval, and calculating an integral area proportion of a partition corresponding to each chemical functional group; based on the molecular mixing model, constructing a linear equation set, and solving the mole fractions of the six chemical components in the soil sample by adopting a constrained least square programming algorithm; and calculating the proportions of plant source carbon, microbial source carbon and pyrolytic carbon in the soil sample according to the calculated mole fractions of the six chemical components. The carbon proportion of a plant source and a microorganism source can be effectively distinguished by combining solid 13C nuclear magnetic resonance and a molecular mixed model, and the carbon stability change in the grassland degeneration and recovery process is revealed.

This invention discloses a method for calculating CO2 stockpiles in abandoned oil reservoirs based on multi-component phase equilibrium analysis, relating to the field of oil and gas field development technology. The invention first calculates the molar concentrations of non-CO2 native hydrocarbon components in the reservoir before and after CO2 injection. Then, it presets an initial value for the CO2 concentration in the reservoir mixture, determines the molar fraction of each component in the mixture under the initial state, and uses the Peng-Robinson equation of state to perform reservoir phase stability analysis under the final stockpiling pressure. This determines the molar fraction of each component in the mixture, obtains the distribution of CO2 and hydrocarbon components in the gas and liquid phases, calculates the true concentration of CO2 in the reservoir mixture, determines the solubility of CO2 in the aqueous phase, and obtains the total CO2 stockpiles in the reservoir. This invention fully considers the influence of porosity elasticity changes and complex component phase states on CO2 stockpiles in the reservoir, improving the accuracy of CO2 stockpil calculation results.

The present invention addresses the problem of providing a mixed gas and a method for regenerating an adsorbent with which it is possible to suppress the pulverization of an adsorbent while removing adsorbed components from the adsorbent. The means for solving the above problem is a mixed gas containing 0.1-3.0 vol% water vapor and 97 vol% or more of a gas A different from the water vapor, wherein the gas A has a Henry's constant with respect to water at 0°C of 2000 atm / mole fraction or less.

The invention provides a preparation method of composite ion pair modified potassium-sodium niobate ceramic, and relates to the technical field of functional ceramic. The chemical general formula of the composite ion pair modified potassium-sodium niobate ceramic is (K0. 5Na0. 5) 1-x (H-V) xNbO3, H-V is a composite ion pair, x is the mole fraction of the composite ion pair, and 0 lt; x is smaller than or equal to 0.05; the composite ion pair H-V is composed of a positive ion H and an equivalent A-site vacancy V, and is used for jointly replacing A-site (K0. 5Na0. 5) 1 + in the chemical general formula and keeping the electricity price balance of a crystal structure. The potassium-sodium niobate ceramic material disclosed by the invention has excellent piezoelectric property, and the maximum piezoelectric coefficient is about 560 pC / N. The performance index is far superior to the electrical performance of pure potassium sodium niobate ceramic, and is also superior to numerous commercial lead-containing PZT piezoelectric ceramics.

The application discloses an electrolyte initial crystallization temperature prediction method, a medium and an electronic device, wherein the method comprises: obtaining to-be-tested electrolyte data, the to-be-tested electrolyte data comprising to-be-tested electrolyte components and mass percentage contents of the to-be-tested electrolyte components; obtaining molar fractions of elements based on the law of conservation of mass, the stoichiometry principle and the elements corresponding to the to-be-tested electrolyte components in the to-be-tested electrolyte data; obtaining point features of each element based on first attributes of the elements, and obtaining edge features between each two elements based on second attributes of the elements and the molar fractions; the first attributes are used for representing inherent physical and chemical attributes of the elements, and the second attributes are used for at least representing interaction strengths determined based on concentration coupling relationships between the elements; and the point features and the edge features are input into a pre-trained neural network prediction model to obtain a predicted electrolyte initial crystallization temperature; and the application improves the prediction accuracy and generalization ability of the initial crystallization temperature.

An ethylene oxide (EO) production process comprising (a) introducing a first reactant mixture (C2H6, C2H4, O2) to a first reactor system to produce a first effluent stream (C2H4, C2H6, O2), wherein the mole fraction of ethylene in first effluent stream is greater than in first reactant mixture; wherein the first reactor system is characterized by a first reactor system operating temperature of 270° C.-320° C.; wherein the first reactor system comprises oxidative dehydrogenation (ODH) stage(s); (b) introducing the first effluent stream to a second reactor to produce a second effluent stream (EO, C2H4, C2H6, O2); (c) separating the second effluent stream into an EO product stream (EO) and recycle stream (C2H4, C2H6, O2); wherein ethylene is not separated from recycle stream and / or first effluent stream; (d) recycling at least a portion of recycle stream to the first reactor system, and a optionally portion of recycle stream to the second reactor.