Use of amino phase adsorbent for biomass tar sampling and separation

To reduce sampling and sample separation time, a highly efficient method based on solid-phase adsorption (s.p.a.) on amino phase was designed. This method is suitable for intermittent trapping of tar compounds ranging from benzene to coronene prevailing in product gases from thermal decomposition of biomass at 700-1000 degrees C. Using eluotropic elution, adsorbates are selectively desorbed into aromatic and phenolic fractions and then determined by gas chromatography with flame-ionization detection. The sampling step allows collection of one to three samples per minute, compared with one or two samples per hour using conventional cold trapping (c.t.) techniques, and correspondingly more information is obtained. As a result of this improvement, the progress of pyrolysis and gasification processes in terms of molecular distribution is easily followed. Furthermore, the method can be readily applied to establish cold-trap and filter performance and for industrial emission control. The usefulness of the method is compared with the cold-trapping techniques and the novel solid-phase micro extraction (s.p.m.e.) technique, not tested earlier for tar sampling. Copyright (C) 1997 Elsevier Science Ltd.