Kinetics of Upgrading of Anisole with Hydrogen Catalyzed by Platinum Supported on Alumina

Abstract

Kinetics of the reactions of anisole, a model compound representative of lignin-derived bio-oils, with H 2 , catalyzed by Pt/Al 2 O 3 , were investigated with a fixed-bed tubular microflow reactor at 573−673 K, 8−14 bar, and space velocities in the range of 3−240 (g of anisole)/(g of catalyst × h). Selectivity−conversion data were used as a basis to propose an approximate reaction network and estimate parameters in approximate rate equations. The reactions include the following: anisole conversion to phenol by hydrogenolysis, to 2-methylphenol by transalkylation, to 2,4-dimethylphenol, 2,4,6-trimethylphenol, and 2,3,5,6-tetramethylphenol by transalkylation and alkylation, to benzene by hydrodeoxygenation (HDO), and to hexamethylbenzene by HDO and alkylation. The primary reactions are satisfactorily represented with the approximation that each is first-order in the organic reactant. The apparent activation energy for the hydrogenolysis reaction that leads to phenol formation is approximately 25.3 kJ/mol, and the alkylation is the reaction class characterized by the highest apparent activation energy.

Hydroprocessing of 4‐methylanisole as a representative of lignin‐derived bio‐oils catalyzed by sulphided CoMo/γ‐Al2O3: A semi‐quantitative reaction network

“…In this research, we extend the work that has been reported characterizing sulphided CoMo/γ‐Al 2 O 3 ‐catalyzed hydroprocessing of compounds representative of lignin‐derived bio‐oils, now including a partial quantitative representation of the reaction network (with kinetics), with 4‐methylanisole chosen as the reactant because it incorporates a benzene ring substituted with both methyl and methoxy groups and is therefore a good representative of lignin‐derived compounds.…”

Experimental Investigation on Upgrading of Lignin‐Derived Bio‐Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst

“…The depolymerization of biomass and the upgrading the resulting fragments into compounds with properties that approximate those of petroleum represent substantial challenges . The compositions of liquids formed from biomass depend on the raw materials and the methods of conversion . Generally, these liquids include high concentrations of oxygen‐containing compounds, and improvements in the stability of these liquids and their compatibility with petroleum products require a reduction in their oxygen contents.…”

“…Among the various polymers present in lignocellulosic biomass, lignin, with its polyaromatic structure, is the one that is chemically most similar to petroleum. Nonetheless, lignin contains much more oxygen than crude oil , and lignin‐derived bio‐oils are good candidates for hydroprocessing for oxygen removal.…”

The utilization of synthesis gas for the deoxygenation of cyclohexanone over alumina‐supported catalysts: Screening catalysts

“…The utilized microflow reactor (Microactivity‐Reference, PID Eng & Tech) for the conversion of cyclohexanone has been well introduced in the previous studies . A fixed‐bed once‐through tubular reactor working in the down‐flow mode and equipped with a porous plate for the catalyst particles was utilized.…”