Cu dispersed ZrO2 catalyst mediated Kolbe- Schmitt carboxylation reaction to 4-hydroxybenzoic acid

Pandey, Preeti H.; Pawar, Hitesh S.

doi:10.1016/j.mcat.2022.112595

Cited by 6 publications

(3 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The yield and purity of salicylic acid was calculated using a standard formula as shown below [ 49 ]:

…”

Section: Methodsmentioning

confidence: 99%

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Mohammad,

Onwudili,

Yuan

2024

Molecules

View full text Add to dashboard Cite

Conversion of CO2 into organic chemicals offers a promising route for advancing the circularity of carbon capture, utilisation, and storage in line with the international 2050 Net Zero agenda. The widely known commercialised chemical fixation of CO2 into organic chemicals is the century-old Kolbe–Schmitt reaction, which carboxylates phenol (via sodium phenoxide) into salicylic acid. The carboxylation reaction is normally carried out between the gas–solid phases in a batch reactor. The mass and heat transfer limitations of such systems require rather long reaction times and a high pressure of CO2 and are often characterised by the low formation of undesirable side products. To address these drawbacks, a novel suspension-based carboxylation method has been designed and carried out in this present study, where sodium phenoxide is dispersed in toluene to react with CO2. Importantly, the addition of phenol played a critical role in promoting the stoichiometric conversion of phenoxide to salicylic acid. Under the optimal conditions of a phenol/phenoxide molar ratio of 2:1 in toluene, a reaction temperature of 225 °C, a CO2 pressure of 30 bar, a reaction time of 2 h, and stirring at 1000 rpm, an impressive salicylic acid molar yield of 92.68% has been achieved. The reaction mechanism behind this has been discussed. This development provides us with the potential to achieve a carboxylation reaction of phenoxide with CO2 more effectively in a continuous reactor. It can also facilitate the large-scale fixing of CO2 into hydroxy aromatic carboxylic acids, which can be used as green organic chemical feedstocks for making various products, including long-lived polymeric materials.

show abstract

“…The yield and purity of salicylic acid was calculated using a standard formula as shown below [ 49 ]:

…”

Section: Methodsmentioning

confidence: 99%

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Mohammad,

Onwudili,

Yuan

2024

Molecules

View full text Add to dashboard Cite

show abstract

“…Recently, tremendous efforts and advancements in biomass utilization, − green hydrogen production, , CO 2 hydrogenation to green methanol (a product of liquid sunshine), − and green ammonia synthesis , have created a sustainable platform for the chemical valorization and extension of the industrial chain. For instance, lignin-derived phenols combined with CO 2 to produce salicylic acid via the Kolbe–Schmidt process, , biomass-based carboxylic acids with green methanol to esters, , biomass-based carboxylic acid/esters reacting with ammonia to amides and/or nitriles, − etc. , these reaction routes are promising and practical for the synthesis of chemical intermediates in pharmaceuticals and polymer materials.…”

Section: Introductionmentioning

confidence: 99%

Kinetics and Mechanism of Integrated Catalytic Ammonolysis and Dehydration from Methyl Salicylate over ZnAl₂O₄ Spinel

Wang,

Xie,

Zeng

et al. 2024

ACS Catal.

View full text Add to dashboard Cite

A kinetic and mechanistic study of direct catalytic nitrilation from methyl salicylate and ammonia is conducted by using an amphoteric ZnAl 2 O 4 spinel as a model catalyst. This overall process integrates the catalytic ammonolysis of esters with the dehydration of amides, proceeding stepwise over the concerted Lewis acid−base pairs of Zn−O−Al linkages. The chemisorption and activation of C−O bonds of the ester over Lewis acid−base pairs facilitate the leaving of the methoxy group, while Lewis basic oxygen (Zn−O*−Al) serves as the main hub station for multistep proton transportation, thus leading to the decreased apparent activation energy of nitrilation and ammonolysis. The combined experimental and computational evidence confirms that this direct nitrilation process follows a monomolecular surface adsorption model, i.e., the Eley−Rideal mechanism, involving eight elementary reaction steps in which chemisorbed surface species of methyl salicylate react with gaseous NH 3 molecules via nucleophilic addition−elimination and multistep proton transfer to generate amides and nitriles in sequence. Microkinetic model discrimination and DFT calculations reveal that the formation of chemisorbed imine (C�N−H) via proton transfer from the Lewis basic oxygen atom (Zn−O*−Al) to the carbonyl oxygen (C�O*) is the ratedetermining step, thereby providing a potential consideration of protonation and deprotonation ability to rationally design an improved catalyst.

show abstract

“…Furthermore, presence of water impedes the carboxylation process, necessitating the drying of starting materials [13]. In industrial processes, dry alkali metal phenolates are typically subjected to carbon dioxide under pressure, facilitating the desired carboxylation reaction [14].…”

mentioning

confidence: 99%

Synthesis and optimization of 2,5-dihydroxyterephthalic acid in a slurry reactor

Beiranvand,

Ovaysi

2024

Preprint

View full text Add to dashboard Cite

2,5-dihydroxyterephthalic acid (DHTA) is synthesized under 10 bar pressure and 200°C temperature. Using a slurry reactor, disodium salt of hydroquinone (DSH) is contacted by carbon dioxide gas in presence of sodium acetate as catalyst. A fractional factorial design is used to screen four parameters including reactor pressure, temperature, catalyst to DSH molar ratio, and reaction time. By performing 8 experiments in the screening phase the variables ranges are modified to 175–200°C for temperature, 1.5–2.5 for catalyst to DSH molar ratio, and 3–5 hours for reaction time. Additionally, pressure is kept fixed at 10 bar throughout the remaining experiments. An additional 14 more experiments devised by Box-Behnken design scheme are performed to determine a quadratic model for the DHTA yield against the three parameters mentioned above. A mathematical optimization of the model predicts 83.385% DHTA yield at 200°C, 2.085, and 250 minutes for temperature, catalyst to DSH molar ratio, and reaction time, respectively. These parameter values are put to the test by performing one more experiment under the suggested optimum point. This results in 83% DHTA yield which is in good agreement with the model. For all experiments, the DHTA yields and the composition of byproducts were obtained using HPLC analysis. The optimized product was analyzed using XRD and FTIR analyses and the structure of the synthesized DHTA was confirmed.

show abstract

Cu dispersed ZrO2 catalyst mediated Kolbe- Schmitt carboxylation reaction to 4-hydroxybenzoic acid

Cited by 6 publications

References 72 publications

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Kinetics and Mechanism of Integrated Catalytic Ammonolysis and Dehydration from Methyl Salicylate over ZnAl₂O₄ Spinel

Synthesis and optimization of 2,5-dihydroxyterephthalic acid in a slurry reactor

Contact Info

Product

Resources

About

Cu dispersed ZrO2 catalyst mediated Kolbe- Schmitt carboxylation reaction to 4-hydroxybenzoic acid

Cited by 6 publications

References 72 publications

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe–Schmitt Reaction in Toluene

Kinetics and Mechanism of Integrated Catalytic Ammonolysis and Dehydration from Methyl Salicylate over ZnAl2O4 Spinel

Synthesis and optimization of 2,5-dihydroxyterephthalic acid in a slurry reactor

Contact Info

Product

Resources

About

Kinetics and Mechanism of Integrated Catalytic Ammonolysis and Dehydration from Methyl Salicylate over ZnAl₂O₄ Spinel