Effect of ultrasound on adsorption of Geniposide on polymeric resin

Abstract

The effects of pulse ultrasound with different pulse parameter on the adsorption isotherm and kinetics of Geniposide on Resin 1300 were studied. And the mass transfer model describing the adsorption process was constructed. Amount of Geniposide adsorbed on Resin 1300 in the presence of ultrasound is lower than that in the absence of ultrasound. At our experimental conditions, the adsorption equilibrium constant decreases with increasing ultrasonic intensity and pulse duty ratio, and with decreasing pulse period. In addition, pulse ultrasound can enhance both liquid film diffusion and intraparticle diffusion, and the intensification of liquid film diffusion with pulse ultrasound is stronger than that of intraparticle diffusion. The intraparticle diffusion coefficient D(e)/R2 increases with increasing ultrasonic intensity and pulse duty ratio, and with decreasing pulse period.

Mass transport and thermodynamic analysis of PAHs in partitioning systems in the presence and absence of ultrasonication

“…Enhancements of this nature (i.e., beyond internally controlled deliveries) would only arise from changes in internal properties and could be attributed to sonic shockwaves generating microscopic turbulence within polymer pores. 27 Similar results have been observed for delivery of various drugs from a number of polymers, in which transport increased as a function of agitation to a certain point, after which rates became independent of mixing. 29 However, as also seen in this study sonicated deliveries were faster than those observed under any mixing conditions examined, suggesting that sonic improvements were not solely external.…”

“…[22][23][24][25] The possibility of using ultrasound for improved PAH transport in polymer-liquid systems has been examined by Isaza and Daugulis 16 and results showed significant enhancements in substrate delivery and degradation. Although previous results and conclusions [26][27][28][29] suggest that sonication enhances internal and external delivery, as well as partitioning coefficients, results to date for PAHs 16 cannot be adequately interpreted to identify specific effects in two-phase systems. A mass transport analysis is, therefore, required to provide such insight.…”

“…However, it is apparent that sonication induced higher PAH concentrations in methanol at equilibrium with similar effects reported in previous studies. [26][27][28] During sonication, bubbles are generated and subsequently collapse, in a process termed cavitation, inducing conditions of several thousand Kelvin and a few hundred bar. Near a solid surface, such as a polymeric matrix, asymmetric bubble collapse forms ''microjets'' reaching speeds up to 500 m/s, which along with sonic shockwaves can break up of interactions between sorbed molecules and sorbent surfaces.…”

Effect of ultrasound on the kinetics of cation exchange in NaX zeolite

“…Comparison of the exchange methods shows that the time to reach equilibrium in the traditional method is shorter than that in the ultrasonic one. Ultrasound also enhanced the exchange amount by means of transient cavitation bubbles which are found not only in the fluid phase surrounding the particles but also in the solution within the porous particles, compared to the traditional method [8,9]. The effect of the fold equivalent excess of Li + and Ca 2+ ion exchanges is also clearly seen: the higher the amount of the ions present in the solution, the higher the exchange amount.…”

“…They found that phenol desorption rates were enhanced with the ultrasound due to an increase in diffusive transport within the pores. In another study, the effect of ultrasound was investigated on the leaching process [8,9]; Geniposide leaching from the Gardenia fruit. Ultrasound increased the external mass transfer and intraparticle diffusion coefficients.…”