Context :

Aims : We focus here on one particular and poorly studied object , IRAS 11472 - 0800 .
It is a highly evolved post-Asymptotic Giant Branch ( post-AGB ) star of spectral type F , with a large infrared excess produced by thermal emission of circumstellar dust .

Methods : We deploy a multi-wavelength study which includes the analyses of optical and IR spectra as well as a variability study based on photometric and spectroscopic time-series .

Results : The spectral energy distribution ( SED ) properties as well as the highly processed silicate N-band emission show that the dust in IRAS 11472 - 0800 is likely trapped in a stable disc .
The energetics of the SED and the colour variability show that our viewing angle is close to edge-on and that the optical flux is dominated by scattered light .
With photospheric abundances of [ Fe/H ] = - 2.7 and [ Sc/H ] = - 4.2 , we discovered that IRAS 11472 - 0800 is one of the most chemically-depleted objects known to date .
Moreover , IRAS 11472 - 0800 is a pulsating star with a period of 31.16 days and a peak-to-peak amplitude of 0.6 mag in V .
The radial velocity variability is strongly influenced by the pulsations , but the significant cycle-to-cycle variability is systematic on a longer time scale , which we interpret as evidence for binary motion .

Conclusions : We conclude that IRAS 11472 - 0800 is pulsating binary star surrounded by a circumbinary disc .
The line-of-sight towards the object lies close the the orbital plane making that the optical light is dominated by scattered light .
IRAS 11472 - 0800 is one of the most chemically-depleted objects known so far and links the dusty RV Tauri stars to the non-pulsating class of strongly depleted objects .