Methanol synthesis: a short review of technology improvements

Scope of Review. This review is written from the point of view of the process design engineer trying to find the best catalytic options for upgrading methane. It is not intended to be a review of catalytic principles. In fact, actual catalysts used are only mentioned in passing. If the reader wishes to explore this aspect further, there are many recent review articles that can be used and these are referred to at an appropriate time and place.

The Different Catalytic Routes for Methane Valorization: An Assessment of Processes for Liquid Fuels

Optimum synthesis gas conversion and high selectivity to DME were attained at the initial H2/CO ratio of in feed gas using hybrid catalyst in a slurry bubble column reactor. The study of process economics led to the estimation that the production cost per a heating value in the DME synthesis was reduced by 20% compared with a conventional methanol synthesis.

Direct Synthesis of Dimethyl Ether form Synthesis Gas

Processes for converting methane to liquid fuels: economic screening through energy management

The sections in this article are


Introduction
Thermodynamics
Methanol Synthesis Catalysts
Introduction
ZnO/Cr2O3 Catalyst
Copper-Based Catalysts
Cu/ZnO + Element (Al, Cr, … )
Promotion of Cu/ZnO/MOx Catalysts
Cu/ZrO2
Other Cu, Cu/Me, Cu/MeOx Catalysts
Pd-Based Catalysts
Sulfide Catalysts
Other Catalysts
Activation of Cu/Zn Catalyst
Activity as a Function of the Nature of Copper-Based Catalysts


Catalyst Deactivation
Sintering
Sulfur Poisoning
Other Poisons


By-Product Formation
Reaction Mechanism(s) and Active Sites
Cu+ in a ZnO Matrix as the Active Center
The Schottky Junction Theory
Partly Oxidized Copper Independent of Support as Active Sites
Metallic Copper in Dynamic Interaction with the Support
Cu–Zinc Surface Alloy Model
Water Gas Shift Reaction


Kinetics
Reaction Rate Equations
Diffusion Restrictions
Kinetics in Slurry Phase Methanol Synthesis


Methanol Synthesis Technology
Synthesis Gas Preparation
Natural Gas Reforming
Adiabatic Pre-Reforming
Tubular, Fired Reforming
Autothermal Reforming and Oxygen-Fired Secondary Reforming
Gasification of Heavy Oil, Coal or Biomass
Coproduction in Ammonia Plants and Use of Off-gases
Economics of Synthesis Gas Preparation
Reactor Systems and Synthesis Loop Layout
Slurry Phase Reactor Types
Methanol Purification
Concepts Circumventing the Equilibrium Limitations
Other Methanol Synthesis Routes and Technologies
Methanol Synthesis by Methane Activation


Conclusion


Keywords:

methanol;
methanol synthesis catalysts

13.13 Methanol Synthesis

Future synfuel production schemes may call for methanol synthesis reactors larger than those in use today. Methanol may be produced in a number of quite different reactor types, and for each type some kind of practical scale-up limit exists. This investigation involves exploring the features of seven kinds of reactors, and a kinetic modeling approach is used where appropriate to determine the maximum methanol production for a unit 6 m in diameter. Reactor types discussed include the Lurgi tubular packed bed system, the ICI quench system, and the Casale mixed flow system. Other variations considered are the conventional fluidized bed, the high-velocity circulating fluidized bed, a tube-cooled radial flow system, and a high-viodage version of the four-stage quench reactor. Of the types discussed, four appear to be capable of producing an excess of 5000 ton of methanol per day in a single, 6-m-i.d. unit: the Cassale system, the tube-cooled radial flow reactor, the circulating fluidized bed, and the high-voidage quench system.

Rodney J. Dry

Papers

Possibilities for the development of large-capacity methanol synthesis reactors for synfuel production