determination of optimum amounts of effective parameters in reactive dyes removal using a zeolitic-imidazolate framework catalyst

determination of optimum amounts of effective parameters in reactive dyes removal using a zeolitic-imidazolate framework catalyst

an efficient and rapid fabrication procedure for zif-8 crystals through ultrasonic assisted strategy (30min) was reported. additionally, the crystallinity, morphology, chemical bonding, and porosity of zif-8 were fully characterized by xrd, and ft-ir. the response surface methodology approach was established to optimize a series of adsorption conditions: initial concentration (10–400 mg/l), dose (0.02–1 g/l), and time (20–60 min) for red 141 and violet-5r removals.

particularly, plausible adsorption mechanisms (electrostatic interactions and π–π stacking) were elucidated, and isotherm models were rigorously studied by three-parameter equations (langmuir, freundlich, tempkin). the adsorption isotherm data showed the adsorption of reactive dyes by zif-8, was consistent with the langmuir isotherm model. the kinetics parameters were in accord with the pseudo-second-order equation, which implied that the adsorption rate was mainly controlled by the chemisorption mechanism. through advantageous effectiveness involving good reusability (4 recycles), and maximum adsorption capacities (250-200 mg/g), it is recommendable to utilize zif-8 as a good adsorbent for the dyes remediation.