Obtaining syngas by dry reforming of methane in a pilot unit

ABSTRACT

Dry reforming of methane (DRM) is an endothermic catalytic process that occurs between 700 and 900 ^oC, capable of converting CH₄ and CO₂ (biogas) into H₂ and CO (syngas). Works have been undertaken in view of developing ideal catalyst for DRM, endeavoring to resolve the problems encountered, such as the case of catalyst deactivation due to coke formation, which reduces the performance of syngas production and may block the catalyst layer. In previous works by the Laboratory of Renewable and Materials Energies (LABMATER) at the UFPR, the catalyst 20Ni / Si-MCM-41 was developed, which has a good performance in the conversion of CH₄ and CO₂ and a low tendency to coke formation (≈ 10 mgC.gcat^-1.h^-1), being a material with a nominal Ni load of 20% (m / m), supported on a molecular sieve based on mesoporous silica (Si-MCM-41) with a high specific surface (≈600 m².g^-1). However, only tests in experimental units using the catalyst in the powdered form have been performed to test the efficiency of the material. In this work, a pilot unit containing a continuous fixed bed reactor was used, with the objective of evaluating the activity of the granular catalyst and its stability in DRM, in order to subsidize the future construction of a reformer on an industrial scale. Four preliminary experiments were performed with a varying reaction composition of 40-70% CH₄: 30-60% CO₂, 3 g of the catalyst 20Ni/Si-MCM-41 in the catalyst layer, temperature of 800 ^oC and a flow rate of the products of 36 Lh^-1 at 1 atm. The tests involving variations in the entry compositions with a duration of 4 hours indicated better results for a mixture 50%CH₄:50%CO₂. Another test of 17 hours was performed, in order to verify the stability of the catalyst and evaluate coke formation during the reaction time and the performance of the pilot unit.

Keywords
hydrogen; mesoporous silica; Si-MCM-41