Synthesis of Acetic Acid via Carboxylation of MethaneEPA Grant Number: R827124
Title: Synthesis of Acetic Acid via Carboxylation of Methane
Investigators: Roberts, George W. , Spivey, James J.
Current Investigators: Roberts, George W. , Spivey, James J. , Wilcox, Esther
Institution: North Carolina State University , Desert Research Institute
Current Institution: North Carolina State University
EPA Project Officer: Shapiro, Paul
Project Period: September 30, 1998 through September 30, 2001 (Extended to June 30, 2002)
Project Amount: $118,119
RFA: Exploratory Research - Environmental Engineering (1998) RFA Text | Recipients Lists
Research Category: Sustainability , Land and Waste Management , Engineering and Environmental Chemistry
This research is designed to explore the direct synthesis of acetic acid, an
important chemical intermediate, by the direct reaction of two greenhouse gases,
methane (CH4) and carbon dioxide (CO2):
The objective is to develop solid, heterogeneous catalysts for this direct synthesis reaction. This provides a means of forming a non-fuel product from two greenhouse gases.
The feasibility of the direct reaction of CO2 and CH4 to form acetic acid has recently been shown at RTI on solid catalysts from a CO2/CH4 gas mixture over a 5% Pd/C catalyst. The formation of the RCOO- group was observed by FTIR by the appearance of bands at 1,743 and 1,790 cm-1. Although experimental homogeneous catalysts have been reported for this reaction (Kurioka et al., 1995; Nishiguchi, 1992), reaction rates are orders of magnitude lower than commercial requirements. Heterogenous catalysts are preferable to avoid separation costs and expensive reactor materials needed for homogeneous catalysts. We will use DRIFTS studies to evaluate transition metal catalysts, e.g., Ni, Fe, Pd, Pt, Rh, Ir, and Cu, on basic supports for their ability to activate CO2 and CH4.
The direct synthesis of acetic acid using CO2 and methane provides an environmentally benign way to consume two greenhouse gases in one process. The use of heterogeneous catalysts for this synthesis has not been reported in the literature. Although an indirect route involving the reforming of CH4 + CO2 -> syngas -> methanol -> acetic acid is possible with conventional technology, the direct route is clearly simpler and therefore potentially economically attractive.