The goal of this project is to optimize the reaction conditions for upgrading coal liquids. Our results for this quarter are summarized: Last quarter we found that H/sub 2/S aids in the HDN process. During this quarter, we have undertaken an H/sub 2/S concentration study on this reaction and found a direct correlation between the amount of added H/sub 2/S and the reduction in nitrogen content. For comparison, we also used H/sub 2/O and Na/sub 2/S as additives; however, neither appears to be as effective as H/sub 2/S in the HDN process. We initiated syntheses of some organometallic molybdenum cluster complexes (Mo/sub 2/(OAc)/sub 4/ and cluster complexes Mo/sub 2/(allyl)/sub 4/) and have reacted these complexes with an alumina support. Preliminary tests reveal that these complexes have, as expected, less hydrogenation activity than the activated CoMo catalyst. However, we have not yet tested them for HDN activities. We began experiments on the addition of added Bronsted acids (C/sub 3/FCOOH) to the reaction system. So far, the results have been promising and indicate a direct correlation between the amount of added acid and the amount of HDN activity. 3 references, 1 figure, 2 tables.