Enhanced Catalyst Activity of WO₃ Using Polypyrrole as Support for Acidic Esterification of Glycerol with Acetic Acid

Table 1

Acidic properties of the samples obtained from TPD of ammonia.

Sample			Temperature at maximum (°C)	Total acidity (mol·g^−1)
WO3	1.38	28.50	350	316
WO3-Ppy-5	9.01	10.73	130, 223, 390	535
WO3-Ppy-10	9.35	10.87	132, 226, 384	659
WO3-Ppy-15	10.84	10.21	134, 227, 407	754
WO3-Ppy-20	11.17	10.16	137, 230, 370	1250
Ppy	10.53	15.29	127, 183, 211	647

Multipoint BET surface area (m² g⁻¹).
^bPore Size (nm).