## 2 Materials and Methods  
### Asphalt Mixture Preparation and Fume Capture  
Asphalt mixtures were designed in the laboratory according to the Marshall Method [65], following the approach for a surface layer, to obtain the optimum proportion of asphalt mix components. The mixtures were not compacted because this is not necessary for fume capture. Raw materials were mixed in a sealed cylindrical reactor (6 L) coupled to a manual stirring system to prevent fumes from leaking. Fluvial aggregates, mainly composed of dolomite, basalt, andesite, rhyolites, sandstone, quartz, and quartzite (12.5 mm sieve size; semi-dense type IV-A-12 aggregate gradation); conventional asphalt binder (CA-24), with absolute viscosity of 3077 P (60 \({}^{\circ}\)C, 300 mm Hg) and a density of 1.04 kg/m\({}^{3}\); and natural clinoptiolite-modernite zeolite (Chemical composition: SiO\({}_{2}\): 64.19%, TiO\({}_{2}\): 0.51%, Al\({}_{2}\)O\({}_{3}\): 11.65%, Fe\({}_{2}\)O\({}_{3}\): 2.53%, MnO: 0.03%, MgO: 0.66%, CaO: 3.42%, Na\({}_{2}\)O: 0.75%, K\({}_{2}\)O: 1.60%, P\({}_{2}\)O\({}_{5}\): 0.03%, PxC: 14.64%) were added to the reactor and treated according to the conditions provided in Table 1. Each asphalt mixture was prepared in triplicate. The RAP used came from milling works of surface course. In order to reduce the heterogeneity of the recycled mixtures, they were fabricated with two fractions of RAP, as recommended by [PERSON] and [PERSON] [66]. The RAP fractions used were 0/5 mm and 5/20 mm. The RAP gradation, the bitumen content for both RAP fractions and the characteristics of binder recovered from the RAP before fractioning, details of the fluvial aggregates, the asphalt binder used, and the mix design properties have all been published previously [67], and the research concluded that these warm mix asphalt and recycled warm mix asphalt performed well in rutting, cracking resistance, fatigue, and moisture damage tests.  
The mixtures were stirred and heated on a magnetic hot plate stirrer for 5 min and allowed to rest for 2 min before fume capture. The fumes (100 mL) were captured using a gas syringe and transferred to hermetic Tedlar gas sampling bags (SKC Inc., Pittsburgh, PA, USA) with a polypropylene valve (Figure 1). Three fume samples were collected from each asphalt mixture.  
The mixtures presented in Table 1 are as follows: P-155: hot mix asphalt produced at 155 \({}^{\circ}\)C; Z0.3-135: warm mix asphalt with 0.3% natural zeolite produced at 135 \({}^{\circ}\)C; Z0.6-135: warm mix asphalt with 0.6% natural zeolite produced at 135 \({}^{\circ}\)C; PR10-155: hot mix asphalt with 10% RAP, produced at 155 \({}^{\circ}\)C; Z0.6-R10-125: recycled warm mix asphalt with 0.6% natural zeolite and 10% RAP, produced at 125 \({}^{\circ}\)C; PR20-155: hot mix asphalt with 20% RAP, produced at 155 \({}^{\circ}\)C; Z0.6-R20-135: recycled warm mix asphalt with 0.6% natural zeolite and 20% RAP, produced at 135 \({}^{\circ}\)C; PR30-155: hot mix asphalt with 30% RAP, produced at 155 \({}^{\circ}\)C; Z0.6-R30-145: recycled warm mix asphalt with 0.6% natural zeolite and 30% RAP, produced at 145 \({}^{\circ}\)C. For all mixes, the asphalt binder was added at 155 \({}^{\circ}\)C and the RAP at ambient temperature (25 \({}^{\circ}\)C). For mixes with RAP, overheating of the natural aggregates was necessary. Contact between the RAP and the overheated natural aggregates produced the desired mixing temperature.