Particle cycle times (average, maximum, and minimum) have been measured in draft tube conical spouted beds for different geometric factors of the contactor (angle and gas inlet diameter), draft tubes (diameter, height of the entrainment zone, and width of the faces) and under different operating conditions (particle density). On the basis of the results, the effects of the type of draft tube and different factors of the contactor/draft tube/particle system have been studied, and those of greater influence have been determined. The results show that particle cycle times and solid circulation rates are highly dependent on the type of draft tube, solid density, and contactor angle. Open-sided draft tubes are the ones with the highest solid circulation rate with stable spouting performance. Therefore, this internal device is a suitable option for scaling up spouted beds with a hydrodynamic performance similar to those without tubes.

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The presence and final destination of pharmaceutical compounds in waters constitute one of the emerging events in current environmental chemistry. Two widely consumed compounds have been evaluated in this study, amoxicillin (AMOX) and diclofenac (DFC), at a concentration of 200 mg L –1 . The presence of both in wastewater has been verified, generating problems in ecosystems and human health. Pyrolysis of hair waste from a tannery process was performed in a fixed-bed reactor. Char was obtained at different operating temperatures (300, 350, 400, and 450 °C), which underwent a characterization of heavy metals and elemental composition. An activation process was applied to the char obtained at 450 °C by means of physicochemical processes and with two chemical agents (KOH and K 2 CO 3 ). For the removal of drugs, two separate tests were performed, one for 28 days and the other one for 4 h, to assess the efficiency and the percentage of removal. It was found that the char obtained at 450 °C is the one that removes most of both compounds: more than 90% of AMOX and more than 80% of DFC.