Microwave-Assisted Digestion of Polyurethane Foam as an Alternative to Elution: Solid Phase Extraction of Cd(II) and Pb(II) for Their Determination in Swimming Pool Waters

Table 1

Microwave oven program used in the wet acid digest of polyurethane foam with a 10.5 mol·L⁻¹ HNO₃ solution.

Step	T (°C)	Ramp (°C·s^−1)	Irradiation time (min)
1	100	1	2
2	230^a	2	30^a
3	50	1	1
4	50	1	1
5	50	1	1

^aValues set after the study of the microwave-assisted digestion conditions (see text for details).