Here, we report the preparation of a series of Na+-doped Ca(OH)2 in nanocrystalline form using a very simple method, and investigation of their catalytic activities towards one step aminolysis and transesterification of used cottonseed oil. The catalyst prepared by doping 3.5 wt% Na in Ca(OH)2 was found to exist in nanocrystalline form (particle size = 25–30 nm) as suggested by TEM and DLS studies and found to have the basic strength of 15.0 < H_ < 18.4 as supported by the Hammett indicator test. Na/Ca(OH)2 was used as a solid catalyst towards the aminolysis and transesterification of used cotton seed oil with diethanolamine and methanol, respectively. The catalyst was found to complete the aminolysis and transesterification of a variety of feedstocks even at room temperature and shows excellent reusability.
