A cost sensitivity study has been made in which the effects of major process parameters on plant investment and operating costs have been determined. A tabulation of the parameters studies is included. Results are reported as changes from the base case values which were obtained from the previously completed phases 1 and 2 evaluations. Three battery limits base case process designs were developed in phases 1 and 2 (dispersed phase, fluid bed, fixed bed), but not all of the variables were evaluated in phase 3 for three designs. A copy of the flow sheet, process description, battery limit investment and operating cost for each of the base case designs is included for reference. A brief summary of the results on economics of the major process variables studied is shown. As a reference case, the base case investment and operating costs are also shown. (Author)