The volume of PE solid walls and closed cells in a sample [V.sub.m] was measured using a gas
pycnometer (AccuPycII, Shimadzu, Kyoto, Japan) under nitrogen environment and porosity was calculated by Eq.
Being: Vs: total volume displaced by sample (mL), Ws: sample weight (g), Wp: weight of the empty
pycnometer (g), Wpt: weight of the
pycnometer filled with toluene (g), Wps: weight of the empty
pycnometer with sample (g), Wpts: weight of the
pycnometer filled with sample and toluene (g), [[rho].sub.tol (20[grados]C)] toluene density at 20[grados]C=0.8623 g/mL [15].
True volume of the samples (excluding pore volume) was measured using a
pycnometer (Model Manual Multi-pycnometer; Qunatachrome, Florida, USA) using the fluid (nitrogen) displacement method.
The density was determined using a
pycnometer of 25 ml, viscosity using the outflow velocity of fluids in capillary tubes at 40[degrees] C, the AV and PV by volumetric titrations and the FP using open device or the Marcusson flashpoint apparatus.
General physical and chemical properties were evaluated that included density (by
pycnometer) using the standard IUPAC method 2.101, kinematic viscosity following ASTM method D445, while iodine value (Wij's method), refractive index (Abbe's refractometer), free fatty acid content (FFA %) and saponification number were determined following standard AOCS methods Cd 1-25, Cc 7-25, Ca 5a-40 and Cd 3-25, respectively.
With the
pycnometer method as per standard ASTM D854, the specific gravity ([G.sub.s]) of the tailings was obtained:
Standard test methods for specific gravity of soild solids by water
pycnometer, West Conshohocken, PA, 2010.
The densities of the cured samples were determined in a
pycnometer at 25[degrees]C, using water as the medium.
[14] ASTM, "Standard test methods for specific gravity of soil solids by water
pycnometer: D854-02," in Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA, USA, 2002.