Advanced, soluble hydroliquefaction and hydrotreating catalysts. Quarterly reports No. 10 and 11, January 1, 1993--May 30, 1993

Abstract

The purpose of the present program is to develop soluble analogs of surface confined catalysts that can be impregnated directly into the coal structure at low temperatures. This approach should avoid problems related to surface area dependence, a two phase (surface-liquid) reaction system and, mass transport limitations. Heteropolyanions (HPAs) offer the opportunity to develop soluble forms of surface confined catalysts. HPAs, are inexpensive, well-characterized, water soluble metal oxide clusters, e.g. [EM {sub 12}O{sub 40}]{sup 14{minus}} where E = Si or P and M = Mo or W. They are easily modified to contain other transition metals such as Co, Ni or Ru and, can be made soluble in organic solvents. The protic forms exhibit extremely high acidities pK{sub a} {approx} 0--2. In addition, selectively modified RPAs can function as low temperature hydrogenation catalysts that exhibit microporosity HPAs are multifunctional catalysts that could be used to promote both hydroliquefaction and hydrotreating. In theory, these functions could be employed sequentially or simultaneously and could permit exceptional control of liquefaction reactions and reaction conditions. Thus, the current research program involves efforts to evaluate HPAs as soluble liquefaction and hydrotreating catalysts, with the goal of developing soluble analogs of surface confined catalysts. Alternately, ifmore » HPAs decompose under useful liquefaction conditions, we will explore the utility of creating bimetallic HPAs that can be impregnated into coal and then decomposed to give high surface area heterogeneous catalyst particles that may still permit us to accomplish the above described goals. The program consists of three major tasks: (1) Preparation of candidate HPA precatalysts; (2) HDN and HDO modeling studies and, (3) Direct liquefaction studies. The following sections outline the research planned in each area.« less