Glycol Production Research Articles

PRIMARY HYPEROXALURIA TYPE I: FROM INFANTILE TO ADULT FORM WITH END-STAGE RENAL FAILURE: RARE CASE AND THERAPEUTIC ASPECTS

Primary hyperoxaluria type I (HP1) is a very rare autosomal recessive inherited metabolic disease due to a hepatic alanine-glyoxylate aminotransferase (AGXT) enzyme deficiency. The result is excessive production and elimination of oxalate and glycolate leading to renal failure and systemic thesaurismosis. Diagnosis is based on oxaluria, followed by genotyping, as confirmation of the type of hyperoxaluria is essential for management and allows prenatal diagnosis. Conservative treatment (pyridoxine, hydration, crystallization inhibitors) is essential and must be early and the surgical management of recurrent calculi is very difficult, and requires the least invasive procedures possibleby experienced urologists in order to preserve as much renal parenchyma as possible. It is a serious disease that is often diagnosed late and its radical treatment requires costly and demanding hepato-renal replacement. Knowledge of thealanine-glyoxylate aminotransferase gene and genetic progress has made its prevention possible through prenatal diagnosis and genetic counseling. In this article, we present the case of a young patient treated for this rare disease since childhood to raise awareness among all medical staff, especially pediatricians, urologists and nephrologists, of this pathology which can be mitigated and whose progression can be slowed down if diagnosed at an early stage not like our patient necessitating liver-renal transplantation as the ultimate treatment.

Hybrid modeling for carbon monoxide gas-phase catalytic coupling to synthesize dimethyl oxalate process

Ethylene glycol (EG) plays a pivotal role as a primary raw material in the polyester industry, and the syngas-to-EG route has become a significant technical route in production. The carbon monoxide (CO) gas-phase catalytic coupling to synthesize dimethyl oxalate (DMO) is a crucial process in the syngas-to-EG route, whereby the composition of the reactor outlet exerts influence on the ultimate quality of the EG product and the energy consumption during the subsequent separation process. However, measuring product quality in real time or establishing accurate dynamic mechanism models is challenging. To effectively model the DMO synthesis process, this study proposes a hybrid modeling strategy that integrates process mechanisms and data-driven approaches. The CO gas-phase catalytic coupling mechanism model is developed based on intrinsic kinetics and material balance, while a Long Short-Term Memory neural network is employed to predict the macroscopic reaction rate by leveraging temporal relationships derived from archived measurements. The proposed model is trained semi-supervised to accommodate limited-label data scenarios, leveraging historical data. By integrating these predictions with the mechanism model, the hybrid modeling approach provides reliable and interpretable forecasts of mass fractions. Empirical investigations unequivocally validate the superiority of the proposed hybrid modeling approach over conventional data-driven models and other hybrid modeling techniques.

Catalytic hydrogenolysis of sorbitol to glycols over chromium oxide silica: Effect of chromium loading

Cr2O3-SiO2 (CrSi) catalysts were prepared using the sol-gel method with varying Cr2O3 loadings (5%, 10%, 15%, 20%, and 25% by weight). The physical properties of the synthesized catalysts were characterized through N2 physisorption analysis, X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM). Additionally, NH3-TPD analysis was employed to assess the acidity of the catalysts. The results indicated the presence of ordered mesopores with uniform pore sizes in the synthesized catalysts. The 20CrSi catalyst exhibited high total acidity, which correlated with its catalytic performance. The catalytic activities of the synthesized samples were tested in the sorbitol hydrogenolysis reaction to produce propylene glycols (PG) and ethylene glycols (EG) in a stirred high-pressure reactor under various process conditions. It was found that 20CrSi catalyst recorded maximum sorbitol conversion (70.08%) at optimum reaction condition. The catalyst was reusable up to 5 times with only a minor activity loss. This work contributes to sustainable and green chemical synthesis from renewable sources, offering insights into catalyst design for efficient glycol production.

Carbon and energy balance of biotechnological glycolate production from microalgae in a pre-industrial scale flat panel photobioreactor

Glycolate is produced by microalgae under photorespiratory conditions and has the potential for sustainable organic carbon production in biotechnology. This study explores the glycolate production balance in Chlamydomonas reinhardtii, using a custom-built 10-L flat panel bioreactor with sophisticated measurements of process factors such as nutrient supply, gassing, light absorption and mass balances. As a result, detailed information regarding carbon and energy balance is obtained to support techno-economic analyses. It is shown how nitrogen is a crucial element in the biotechnological process and monitoring nitrogen content is vital for optimum performance. Moreover, the suitable reactor design is advantageous to efficiently adjust the gas composition. The oxygen content has to be slightly above 30% to induce photorespiration while maintaining photosynthetic efficiency. The final volume productivity reached 27.7 mg of glycolate per litre per hour, thus, the total process capacity can be calculated to 13 tonnes of glycolate per hectare per annum. The exceptional volume productivity of both biomass and glycolate production is demonstrated, and consequently can achieve a yearly CO2 sequestration rate of 35 tonnes per hectare. Although the system shows such high productivity, there are still opportunities to enhance the achieved volume productivity and thus exploit the biotechnological potential of glycolate production from microalgae.

Selective Electrified Propylene-to-Propylene Glycol Oxidation on Activated Rh-Doped Pd.

Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.

Biobased propylene glycol production in a sugarcane biorefinery through lactic acid, glycerol, or sorbitol: A techno-economic and environmental evaluation of intermediates and downstream processing methods

Propylene glycol (PG) is a versatile chemical which can be produced by direct fermentation of sugars or through intermediates like lactic acid (LA), glycerol and sorbitol. Few studies have examined producing PG from different intermediates in terms of economic feasibility. In this study, seven process scenarios were assessed in a biorefinery annexed to an existing sugar mill. Aspen simulations were developed for each scenario as the basis for mass and energy balances, techno-economic, and environmental evaluations. Scenario 1 (LA intermediate) had the lowest minimum selling price (MSP) of 1991 US$t−1 and greenhouse gas (GHG) emissions of 1.24 kgCO2/kgPG which was the best intermediate investigated. Scenario 2a-2d (glycerol intermediate) was used to offer insights on the economic benefits of different design changes to the process. Scenario 2a investigates the use of reactive distillation as opposed to normal distillation in the other scenarios. Scenario 2c and 2d offer insights on the purchasing of green hydrogen as an alternative to producing onsite and effect of increased hydrogen ratios respectively. The MSP for the scenarios ranged from 2121–2863 US$.t−1 and GHG emissions of 0.8–2.2 kgCO2/kgPG. Scenario 3 (sorbitol intermediate) had the poorest performance with an MSP of 2751 US$t−1 and GHG emissions of 2.22 kgCO2/kgPG. Scenario 4 (combined first and second-generation feed) had an MSP of 2065 US$t−1 and 1.04 kgCO2/kgPG for GHG.

Dynamic regulation and cofactor engineering of escherichia coli to enhance production of glycolate from corn stover hydrolysate

Glycolic acid is widely employed in chemical cleaning, the production of polyglycolic acid-lactic acid, and polyglycolic acid. Currently, the bottleneck of glycolate biosynthesis lies on the imbalance of metabolic flux and the deficiency of NADPH. In this study, a dynamic regulation system was developed and optimized to enhance the metabolic flux from glucose to glycolate. Additionally, the knockout of transhydrogenase (sthA), along with the overexpression of pyridine nucleotide transhydrogenase (pntAB) and the implementation of the Entner-Doudoroff pathway, were performed to further increase the production of the NADPH, thereby increasing the titer of glycolate to 5.6 g/L. To produce glycolate from corn stover hydrolysate, carbon catabolite repression was alleviated and glucose utilization was accelerated. The final strain, E. coli Mgly10-245, is inducer-free, achieving a glycolate titer of 46.1 g/L using corn stover hydrolysate (77.1 % of theoretical yield). These findings will contribute to the advancement of industrial glycolate production.

Oxygen-Activated Boron Nitride for Selective Photocatalytic Coupling of Methanol to Ethylene Glycol.

The controllable photocatalytic C-C coupling of methanol to produce ethylene glycol (EG) is a highly desirable but challenging objective for replacing the current energy-intensive thermocatalytic process. Here, we develop a metal-free porous boron nitride catalyst that demonstrates exceptional selectivity in the photocatalytic production of EG from methanol under mild conditions. Comprehensive experiments and calculations are conducted to thoroughly investigate the reaction mechanism, revealing that the OB3 unit in the porous BN plays a critical role in the preferential activation of C-H bond in methanol to form ⋅CH2OH via a concerted proton-electron transfer mechanism. More prominent energy barriers are observed for the further dehydrogenation of the ⋅CH2OH intermediate on the OB3 unit, inhibiting the formation of some other by-products during the catalytic process. Additionally, a small downhill energy barrier for the coupling of ⋅CH2OH in the OB3 unit promotes the selective generation of EG. This study provides valuable insights into the underlying mechanisms and can serve as a guide for the design and optimization of photocatalysts for efficient and selective EG production under mild conditions.

Oxygen‐Activated Boron Nitride for Selective Photocatalytic Coupling of Methanol to Ethylene Glycol

AbstractThe controllable photocatalytic C−C coupling of methanol to produce ethylene glycol (EG) is a highly desirable but challenging objective for replacing the current energy‐intensive thermocatalytic process. Here, we develop a metal‐free porous boron nitride catalyst that demonstrates exceptional selectivity in the photocatalytic production of EG from methanol under mild conditions. Comprehensive experiments and calculations are conducted to thoroughly investigate the reaction mechanism, revealing that the OB3 unit in the porous BN plays a critical role in the preferential activation of C−H bond in methanol to form ⋅CH2OH via a concerted proton‐electron transfer mechanism. More prominent energy barriers are observed for the further dehydrogenation of the ⋅CH2OH intermediate on the OB3 unit, inhibiting the formation of some other by‐products during the catalytic process. Additionally, a small downhill energy barrier for the coupling of ⋅CH2OH in the OB3 unit promotes the selective generation of EG. This study provides valuable insights into the underlying mechanisms and can serve as a guide for the design and optimization of photocatalysts for efficient and selective EG production under mild conditions.

Peritoneal B Cells Play a Role in the Production of Anti-polyethylene Glycol (PEG) IgM against Intravenously Injected siRNA-PEGylated Liposome Complexes.

Polyethylene glycol (PEG)-modified (PEGylated) cationic liposomes are frequently used as delivery vehicles for small interfering RNA (siRNA)-based drugs because of their ability to encapsulate/complex with siRNA and prolong the circulation half-life in vivo. Nevertheless, we have reported that subsequent intravenous (IV) injections of siRNA complexed with PEGylated cationic liposomes (PLpx) induces the production of anti-PEG immunoglobulin M (IgM), which accelerates the blood clearance of subsequent doses of PLpx and other PEGylated products. In this study, it is interesting that splenectomy (removal of spleen) did not prevent anti-PEG IgM induction by IV injection of PLpx. This indicates that B cells other than the splenic version are involved in anti-PEG IgM production under these conditions. In vitro and in vivo studies have shown that peritoneal cells also secrete anti-PEG IgM in response to the administration of PLpx. Interleukin-6 (IL-6) is a glycoprotein that is secreted by peritoneal immune cells and has been detected in response to the in vivo administration of PLpx. These observations indicate that IV injection of PLpx stimulates the proliferation/differentiation of peritoneal PEG-specific B cells into plasma cells via IL-6 induction, which results in the production of anti-PEG IgM from the peritoneal cavity of mice. Our results suggest the mutual contribution of peritoneal B cells as a potent anti-PEG immune response against PLpx.

A novel reactive-extractive distillation process for separation of water/methanol/tetrahydrofuran mixtures

The design of separation systems for the purification of azeotropic mixtures is of great importance in the chemical industries from economic and environmental points of view. Two novel reactive-extractive distillation (RED) processes, new design (I) and new design (II), were proposed for separating the azeotropic mixture of water/methanol/tetrahydrofuran (THF). These processes were compared to a conventional extractive distillation (ED) process. New design (I) employs dimethyl sulfoxide as a solvent, while new design (II) utilizes ethylene glycol. Ethylene oxide was introduced to the first column in both designs, enabling the in-situ production of ethylene glycol, a valuable byproduct. This is a novel solution to separate water from the azeotropic mixture by reaction between ethylene oxide and water. Aspen Plus software was used to simulate and design the processes. Both suggested designs were compared economically with the base design which is an ED process. According to the results, the new design (I) is more cost-effective and environmentally friendly alternative to the base design and the new design (II). It has a lower total capital cost and produces less carbon dioxide. Additionally, it generates a valuable by-product, ethylene glycol, which can be sold for substantial revenue. As a result, the new design (I) is the preferred choice for replacing the conventional extractive distillation method.

Fine-Tuning the Expression of the Glycolate Biosynthetic Pathway in Escherichia coli Using Synthetic Promoters

Glycolate plays an important role as a platform chemical in both polymeric material and cosmetic industries. However, the microbial production of glycolate often encounters challenges associated with unbalanced metabolic flux, leading to a notably low titer. Additionally, the use of expensive inducers, such as IPTG, contributes to an increase in the overall production cost. To address these issues, the key enzymes involved in the glycolate biosynthetic route, including citrate synthase (gltA), isocitrate lyase (aceA), isocitrate dehydrogenase kinase/phosphatase (aceK) and glyoxylate reductase (ycdW), were overexpressed in E. coli under the control of inducible promoters with varying strengths in order to determine the optimal combination. Subsequently, the glycolate pathway was further modulated by replacing inducible promoters with various constitutive synthetic promoters. Through this systematic optimization, the best strain, named Mgly4T1562, produced 3.02 g/L glycolate with 97.32% theoretical yield in shake-flask cultivation. The titer further increased to 15.53 g/L in a fed-batch experiment. Notably, this study marks the first successful utilization of synthetic promoters in tuning the glycolate biosynthetic pathway for glycolate biosynthesis. The strategy presented in this research holds significant promise for facilitating the cost-effective and industrially viable production of glycolate without the need for expensive inducers.

Photodynamic Therapeutic Effect during 5-Aminolevulinic Acid-Mediated Photodynamic Diagnosis-Assisted Transurethral Resection of Bladder Tumors.

Photodynamic diagnosis-assisted transurethral resection of bladder tumors (PDD-TURBT) enhances detection of elusive lesions compared to standard white light-transurethral resection of bladder tumors (WL-TURBT). If minimal light exposure during PDD-TURBT induces the accumulation of reactive oxygen species (ROS), potentially resulting in phototoxicity in small lesions, apoptosis may be triggered in residual small tumors, allowing them to escape resection. We investigated the hypothesis of a potential photodynamic therapeutic effect during PDD-TURBT. Our study, conducted between January 2016 and December 2020 at Nara Medical University Hospital, focused on a specific emphasis on ROS production. Immunohistochemical analysis for thymidine glycol and N ε -hexanoyl-lysine was performed on 69 patients who underwent 5-aminolevulinic acid-mediated PDD-TURBT and 28 patients who underwent WL-TURBT. Additionally, we incrementally applied the minimal irradiation energy to T24 and UM-UC-3 cells treated with 5-aminolevulinic acid using instruments similar to those used in PDD-TURBT and evaluated intracellular ROS production and phototoxicity. Immunohistochemical analysis revealed a significant increase in production of thymidine glycol and N ε -hexanoyl-lysine within the PDD-TURBT group. In T24 and UM-UC-3 cells treated with 5-aminolevulinic acid and light exposure, immunofluorescent staining demonstrated a dose-dependent increase in intracellular ROS production. In addition, higher irradiation energy levels were associated with a greater increase in ROS production and phototoxicity, as well as more significant decrease in mitochondrial membrane potential. Although the irradiation energy used in PDD-TURBT did not reach the levels commonly used in photodynamic therapy, our findings support the presence of a potential cytotoxic effect on bladder lesions during PDD-TURBT.

Unlocking the value of food waste: sustainable production of ethylene glycol over low-cost Ni–W catalysts supported on glucose-derived carbons

Low-cost Ni–W catalysts supported on glucose-based carbons were efficient for the sustainable ethylene glycol production directly from cellulose and wastes.

Enhancing the ketonization ability of CeO2 for deoxygenation of biomass-derived sugars by Fe doping

Ketonization of oxygenated compounds in pyrolytic products of biomass is an effective means for deoxygenation and upgrading of bio-oils. However, the ketonization potential of biomass-derived sugars and the mechanism underneath remain unclear. On this basis, a series of Fe doped CeO2 catalysts were synthesized and employed for catalytic ketonization of xylan. Characterization of the catalysts proved the successful formation of the Fe-CeOx solid solution. Doping an appropriate amount of Fe (20–33%) ions on CeO2 could obviously increase the number of oxygen vacancy and basic sites by up to 56.31% and 29.6%, respectively. During the catalytic reaction of xylan, pure CeO2 exhibited a good ketonization ability during xylan pyrolysis, and the introduction of a certain amount of Fe further enhanced the ability. The highest yield of ketones was obtained by 33%Fe-CeO2, which was 38% higher than pure CeO2. The selectivity to linear ketones (acetone and 2-butanone) reached a maximum of 85% for 57%Fe-CeOx. Thus, oxygen-rich compounds had been converted to low oxygen containing and high-quality ketone components. Introducing Fe into CeO2 favored the production of ethylene glycol rather than 2,3-dihydroxy propanal, and thus promoted the yield of acetone. This investigation provides fundamentals for the deoxygenation of biomass through catalytic ketonization, aiming at the production of value-added ketone products.

Implementation and Analysis of a Digital Twin for Propylene Glycol Production: Dynamic Simulation and Process Statistical Control

Purpose: Development of a dynamic simulation and analysis system for Propylene Glycol production through the hydrolysis of Propylene Oxide, utilizing market-available tools including a Digital Twin developed in the Unisim/Honeywell Simulation integrated to the PI System AVEVA/OSIsoft. This system aims to provide a realistic industrial environment for subsequent analysis and statical quality control. Theoretical framework: The manufacturing of Propylene Glycol involves complex reactive systems that require precise control and optimization. The integration of advanced simulation tools and statistical control charts, such as Shewhart Control Charts, is pivotal in monitoring and enhancing the quality of the process. This approach addresses the need for efficient process management in the chemical industry. Method/design/approach: The project employs a decoupled simulation structure, where the reactive system and the statistical control system operate simultaneously, exchanging information through the PI System supervisory software (AVEVA/OSIsoft) and a Python programming environment. The implementation of Shewhart Control Charts within the simulation provides real-time process quality monitoring. Results and conclusion: The outcomes demonstrate the feasibility of using a combination of software tools for daily industrial event simulation, as well as for training and acclimatizing engineers and operators. The analysis of statistical control charts allows for the detection of special cause variations, offering valuable insights for efficient process intervention, thereby enhancing the quality of both the process and the final product. Research implications: This study contributes to a deeper understanding of reactive systems in chemical engineering and the effective integration of simulation and statistical process control techniques. Originality/value: The development of a simulation framework that combines Digital Twin technology with statistical process control for the efficient and reliable production of Propylene Glycol.

Effect of slicing parameters on the light transmittance of 3D-printed polyethylene terephthalate glycol products

To manufacture 3D-printed polyethylene terephthalate glycol (PETG) products with excellent light transmittance performance, this study evaluated the principle of light transmission and the influencing factors of fused deposition methods (FDM) 3D-printed PETG products. This study explored the influence of different slicing parameters (layer height, extrusion rate, and printing speed) on the light transmittance of PETG products via a UV-visible spectrophotometer. The results showed that, in the range of 0.1 to 0.3 mm, the PETG specimens with 0.2 mm layer height had the best light transmittance performance; in the range of 100% to 120%; the PETG specimens with 110% extrusion rate had the best light transmittance performance; in the range of 20 to 40 mm/s printing speed, the PETG specimens with 40 mm/s printing speed had the best light transmittance performance. Comparison of image visibility showed that PETG products with layer height of 0.2 mm, extrusion rate of 110%, and printing speed of 40 mm/s had the best image visibility.

Nickel-tungsten co-doped biochar catalyst boosting ethylene glycol production from cellulose hydrogenolysis

Promoted ethylene glycol (EG) yield from cellulose hydrogenolysis is achieved via using Nickel-tungsten doped carbon catalysts prepared from glucose (x%Ni-y%WOx-GCT). Synchronously metal loading and carbon formation endow the catalyst excellent catalytic performance and high stability. Mechanistic investigations of the effects of metal loading and BrØnsted acid on EG yield are conducted. Increasing W loading promotes the content of polymerized WOx and consequently increases the amount of polytungstate species, thus lead to an improved BrØnsted acid content. Results reveal that promotion of B/L acid facilitates cellulose hydrolysis and suppresses isomerization of glucose to fructose. Besides, high W loading is beneficial for reduction of WOx to form W5+, producing oxygen vacancies to promote retro aldol condensation (RAC) of glucose to form acetaldehyde alcohol (an important intermediate for EG). By adopting the optimized 9%Ni-12%WOx-GC700 catalyst, a 100% cellulose conversion with a high EG yield of 65% is obtained due to the synergistic interactions between BrØnsted acid, W5+ and Ni0+ active sites.

Mechanistic study of the production of ethylene glycol diacetate as a byproduct of the ethylene vapor phase process for vinyl acetate on PdAu(100) surface

With the rapid development of the photovoltaic industry, the demand for new materials such as EVA resin is increasing, and the study of its synthetic monomer vinyl acetate is of great significance. The ethylene vapor phase process is the current mainstream method for producing ethylene acetate. This method mainly uses a PdAu bimetallic catalyst to catalyze the production of ethylene acetate and water from ethylene, acetic acid and oxygen. The reaction process produces ethylene glycol diacetate, a high boiling point byproduct, which not only increases the energy consumption for separating the byproduct and reduces the selectivity of the target product but also may lead to catalyst deactivation. Therefore, reducing its production is of great importance in industrial production. The production mechanism of ethylene glycol diacetate is not clear due to the large variety of surface species and the complexity of the reaction in the ethylene vapor phase method, which makes it challenging to investigate the production mechanism of ethylene glycol diacetate directly by experimental means without interference. Molecular simulation techniques, especially Density Functional Theory (DFT) simulations and kinetic Monte Carlo (kMC) simulations, allow for a targeted study of the catalyst surface reaction mechanism to obtain the mechanism of ethylene glycol diacetate production.In this paper, the elementary reaction in the possible formation path of ethylene glycol diacetate on PdAu(100) surface has been studied by the DFT simulations, and the energy barrier and reaction heat of each elementary reaction have been obtained. Moreover, based on the DFT simulation data, the generation process of ethylene glycol diacetate on PdAu(100) surface is investigated by the kMC simulation, including the processes of reactant adsorption, intermediate species diffusion, surface reaction, and product desorption. The calculation results show that the species are mainly adsorbed on the Pd-Au bridge site or Pd top site; ethylene can firstly generate CH3COOCH2CH2, CH3COOCHCH2 or CH3COOCHCH species and then be combined with CH3COO species to produce ethylene glycol diacetate, where the energy barrier of the reaction of CH3COOCH2CH2 species with CH3COO species is lower than other two species with CH3COO species. The advantage generation path for the ethylene glycol diacetate on PdAu(100) surface is CH2CH2→CH3COOCH2CH2→CH3COOCH2CH2OCOCH3, and the rate-determining step is the reaction of ethylene with CH3COO species to form CH3COOCH2CH2 species.

Simulation Of The Optimum Operating Conditions For A Propylene Glycol Production Unit Using Aspen Hysys Software

Commercially, propylene glycol is produced by the direct hydrolysis of propylene oxide with water. This first-order, irreversible, exothermic reaction is performed in a glass-lined Continuous Stirred Tank Reactor (CSTR). In this study, the initiation of a CSTR was modelled from first principles and simulated using Aspen Hysys 3.2 to obtain concentration and temperature profiles. It is often very important how these profiles approximate the steady-state values. For example, when approaching a steady state the temperature may rise too high and this leads to degradation of the reactant or product, or the altitude may be unacceptable for safe operation. If either condition occurs, the system will exceed its practical stability limit. The practical stability limit represents the temperature above which it is undesirable to operate due to undesirable side reactions or equipment damage. Therefore, the best-operating conditions were obtained in terms of the flow rate of the raw material and the temperature of the reactor at 345 Kgmol/h and 82.2 °C on straight. The production of propylene glycol in the presence of an acid catalyst in an isothermal tank reactor is presented using advanced process simulation software. The effect of temperature was also calculated using the principle of energy balance on the reactor. The reactor operates optimally at a fractional conversion of 0.995 to obtain optimal values for the most important variables/parameters [reactor volume 7.92 m3, reactor length 2.83 m, reactor diameter 1.89 m, and amount of heat required for cooling per unit volume of the reactor 1205 kw].