Solid 3D titanium dioxide (TiO2) structures with hexagonhelical (3DHH) geometry were possible to achieve through additive printing technology. The monoliths acquired the shape and hydrodynamic requirements of a tubular solar CPC photoreactor. The optimum printing parameters were achieved with a 1.2 mm ∅ nozzle, and a dosing rate of 0.87 ml/min, with a duration of 10 min per complete manufactured piece. The heat treatment (Tam⇨180°C30 min ⇨250°C30 min ⇨350°C30 min) applied to the printed pieces does not modify the active anatase/rutile weight ratio (82.9/17.1). On the contrary, the mechanical resistance improved remarkably after the heat treatment: a compressive stress 5 folds higher (307.81 ± 15.31 kPa) was observed in comparison with the pieces without heat treatment. The most important shrinkage in diameter and height are generated throughout the dehumidification process at room temperature of free drying for 24 h (Δ∅ = 3.86 ± 0.43 mm and Δh = 3.78 ± 0.16 mm respectively). In contrast, the size changes were insignificant after heat treatment (Δ∅ = 0.075 ± 0.12 mm and Δh = 0.15 ± 0.01 mm). The microscopic morphology shows changes on the surface of the monoliths with deagglomerated flat shapes after heat treatment. Persistent degradation of the IBP model compound was observed over 10 cycles under solar irradiation in a laboratory-scale photoreactor using twelve heat-pretreated 3DHH-TiO2 monoliths. In addition, 10 cycles were compared for monoliths without thermal processing. Including both cases (monoliths with and without heat treatment), 90% of the solar experiments degraded between 50 and 95% of the initial IBP concentration per cycle (200 mg/L).The resistance to erosion acquired by heat treatment allows mechanical stability for photocatalytic purposes while maintaining significant solar activity. The commercial use of heterogeneous photocatalytic processes on an industrial scale could soon be achieved with the support of 3D additive manufacturing.