Control of the acid site distribution on MCM-68 zeolite catalysts can be achieved by the acid treatment with nitric acid. Less coke is deposited during DTO reactions over dealuminated MCM-68 compared to the parent MCM-68 probably due to the selective removal of acid sites on the external surface of the parent MCM-68. The higher yields of propylene and butylenes are obtained with lower selectivity for ethylene and lower paraffins over dealuminated MCM-68, whereas ethylene and lower paraffins are predominant over parent MCM-68. The acid treatment may preferentially remove the strong acid sites, and thus the retained acid sites with moderate strength mainly convert dimethyl ether into propylene and butylenes with high propylene/ethylene (P/E) molar ratio. Besides the issue of high P/E ratio, the ratio is also widely controllable by changing the reaction temperature. (C) 2014 Elsevier Inc. All rights reserved.