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Obscuring circumnuclear dust is a well-established constituent of activegalactic nuclei (AGN). Traditionally referred to as the receding dusty torus,its inner radius and angular extension should depend on the photo-ionizingluminosity of the central source. Using a Monte Carlo approach, we simulate theradiative transfer between the multiple components of an AGN adopting modelconstraints from the bright Seyfert galaxy NGC 4151. We compare our modelresults to the observed near-IR to UV polarization of the source and predictits X-ray polarization. We find that the 2-8 keV polarization fraction of astandard AGN model varies from less then a few percent along polar viewingangles up to tens of percent at equatorial inclinations. At viewing anglesaround the type-1/type-2 transition the X-ray polarization variability differsbetween a static or a receding torus scenario. In the former case, the expected2-8 keV polarization of NGC 4151 is found to be 1.21% +/- 0.34% with a constantpolarization position angle, while in the later scenario it varies from 0.1% to6% depending on the photon index of the primary radiation. Additionally, anorthogonal rotation of the polarization position angle with photon energyappears for very soft primary spectra. Future X-ray polarimetry missions willbe able to test if the receding model is valid for Seyfert galaxies seen at aviewing angle close to the torus horizon. The overall stability of thepolarization position angle for photon indexes softer than {\Gamma} = 1.5ensures that reliable measurements of X-ray polarization are possible. Wederive a long-term observational strategy for NGC 4151 assuming observationswith a small to medium-size X-ray polarimetry satellite.

X-ray polarimetric signatures induced by spectral variability in the framework of the receding torus model