Alumina support compositions comprising at least 0.1 wt % of silica are disclosed. The alumina support are characterized by a pore volume of greater than 0.60 cc/g, a median pore size ranging from about 70 to about 120, a pore size distribution such that at least 90% of the total pore volume falls within the range of about 20 to about 250, and a pore size distribution width of no less than about 40. Alumina compositions of the present invention exhibit a primary peak mode at a pore diameter less than the median pore diameter. Also provided are catalysts made from the alumina supports, and processes of preparing and using the supports and catalysts.