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To investigate the effect of porosity on elution of volatiles from a devolatilizing coal particle under pulverized coal combustion (PCC) type heating rate conditions, polystyrene was doped into porous model char (Spherocarb) particles and also coated on the surface of nonporous model char (Glassy Carbon) particles. Particles of approximately 80 µm (( 10 µm) diameter were then individually handpicked. These 80 µm diameter particles were heated to a temperature in the range of 1200-2000 K in 32 ms by means of two converging CO 2 laser beams. The eluted products were analyzed by combined gas chromatography/mass spectrometry (GC/MS). The evolved product information was used to construct yield curves. These yield curves were compared to a simple first-order rate law prediction. It was observed that while the styrene yield profile was predicted satisfactorily in the case of nonporous Glassy Carbon, styrene evolution rates were approximately four times slower than predicted in the case of porous Spherocarb. Also, the ratio of secondary pyrolysis products of polystyrene (benzene, toluene, etc.) to a primary pyrolysis product (styrene) was approximately four times higher in the case of Spherocarb than in the Glassy Carbon case. Both findings strongly suggest the presence of transport limitations in porous Spherocarb under PCC-type heating rate conditions.