The effect of adding boron (0.05-0.2 wt.%) and silver (0.5 wt.%) on the performance of Mo/H-ZSM-5 catalysts has been investigated. The results indicate that at the levels studied, boron did not influence the conversion level but improved the selectivity for C-2 hydrocarbons with increasing boron content, while the selectivity for aromatics was decreased when the boron content was more than 0.05 wt.%. The selectivity for C-2 hydrocarbons was increased from 4.5 to 9.5% for a boron loading of 0.2 wt.%. The presence of silver in Mo/H-ZSM-5 catalysts increased the conversion as well as the selectivity for C2 hydrocarbons and aromatics. The catalysts were characterised using TPR, NH3-TPD, UV-vis DRS, FTIR and XPS. (c) 2008 Elsevier B.V. All rights reserved.