Simulation of hybrid trickle bed reactor-reverse osmosis process for the removal of phenol from wastewater

YesPhenol and phenolic derivatives found in different industrial effluents are highly toxic and extremely harmful to human and the aquatic ecosystem. In the past, trickle bed reactor (TBR), reverse osmosis (RO) and other processes have been used to remove phenol from wastewater. However, each of these technologies has limitations in terms of the phenol concentration in the feed water and the efficiency of phenol rejection rate. In this work, an integrated hybrid TBR-RO process for removing high concentration phenol from wastewater is suggested and model-based simulation of the process is presented to evaluate the performance of the process. The models for both TBR and RO processes were independently validated against experimental data from the literature before coupling together to make the hybrid process. The results clearly show that the combined process significantly improves the rejection rate of phenol compared to that obtained via the individual processes

Adsorption of Para Nitro-phenol by activated carbon produced from Alhagi

This manuscript has present an experimental study for Para Nitro-phenol (PNP) removal from aqueous solution using by physiochemical Alhagi activated carbon (AAC). AAC was characterized using SEM to investigate surface morphology and BET to estimate the specific surface area. The best surface area of AAC was found to be 641.6 m2/gm which was obtained at 600ºC activation temperature and impregnation ratio of 1:1 of KOH. The investigated factors for PNP ions adsorption and their ranges such as initial concentration (10-50 mg/L), adsorption time (30-210 min), temperature (20-50ºC) and solution pH (4-10). Isotherm of adsorption and its kinetics were studied. The adsorption process was modeled statistically by an empirical model. The equilibrium data were fitted to the Langmuir and Freundlich isotherm models and the data found to be well represented by Langmuir isotherm. Pseudo- first order and pseudo- second order kinetic equations were utilized to study adsorption kinetics. It is found that the PNP adsorption on AAC fitted pseudo- second more adequately and the best removal efficiency was found to be 97.59%

Magnetic field induced zinc ferrite distribution in mixed matrix membrane for phenol removal

The mixed matrix membrane typically has the particles randomly dispersed within the membrane. The random particle dispersion will reduce the adsorption and photocatalytic performance because the optimum position for particles in the membrane is near the membrane surface. At the optimum position, the particles will easily interact with the incoming targeted molecule, i.e., phenol. One of the methods to disperse the particles near the membrane is by magnetic induce casting. Hence, the first objective was to analyze the effect of magnet arrangement in magnetic induced casting on zinc ferrite distribution in the membrane for phenol adsorption. Next, was to elucidate the impact of different zinc ferrite dosage on magnetic induced casting at varied initial phenol concentrations via adsorption kinetic, isotherm, and diffusion model. The final objective was to investigate the effect of varied magnetic strength on the distribution of zinc ferrite particles in the membrane for photocatalytic degradation of phenol. The particle in this work refers to zinc ferrite, while the magnetic induced casting refers to a step during the membrane fabrication in which the cast film was exposed to magnets in different arrangements with a unique magnetic field for inducing particle distribution and migration. The membrane performance was tested by water flux, phenol adsorption, regeneration while the adsorption data were fitted into adsorption isotherm and kinetic model. For testing the hypothesis, the magnetic induced casting was carried out by arranging the magnets into the rod, circular (MB), and chain (MC) pattern while the zinc ferrite composition was varied at 3, 12 and 30 wt%. The distance between the magnet and cast film was varied to 10, 15 and 40 mm to study the influence of magnetic strength. The findings show that magnet arranged in a chain and circular pattern produced a membrane with high phenol adsorption, fast water flux and stable performance after three regeneration cycle. Circular/12wt% ZnFe (MB12) membrane reported 30.4 L/m2.h water flux with a phenol adsorption capacity of 415 mg phenol/g ZnFe (mg/g). Meanwhile, the finding shows that membrane with 3 wt%/total solid has a stable performance compared to other compositions of zinc ferrite. In studying the effect of zinc ferrite composition, the magnetic arrangement was fixed to a MC and MB pattern. Circular/3wt% ZnFe (MB3) membrane possessed a balanced water flux and phenol adsorption performance with both registering ~27 L/m2.h and ~303 mg/g, respectively. The adsorption kinetic model revealed that the diffusion in the MB3 membrane was propelled by intraparticle diffusion due to low external mass transfer coefficient, Ks = 0.000633, while the chain/3wt% ZnFe (MC3) membrane was rate-limited by external diffusion with Ks of 0.00254. The zinc ferrite adsorption stage implied that the MB3 membrane possessed a zone IV: drastic kinetic, the fastest adsorption rate, while the MC3 membrane exhibited zone III: quick kinetic, a moderate adsorption rate. Furthermore, varying the distance between magnetic and cast film revealed that the circular/12wt% ZnFe/15mm gap (MB1215) membrane demonstrated the highest photocatalytic performance with a stable photodegradation after three regeneration cycles at 1736, 1706, and 1693 mg/g phenol degradation capacity per cycle. A prolonged photocatalytic run indicated the MB1215 degraded ~98% phenol after 510 min

Simulation of reverse osmosis process: Novel approaches and development trends

Reverse osmosis is an essential technological separation process that has a large number of practical applications. The mathematical simulation is significant for designing and determining the most effective modes of membrane equipment operation and for a deep understanding of the processes in membrane units. This paper is an attempt at systematization and generalizing the results of the investigations dedicated to reverse osmosis simulation, which was published from 2011 to 2020. The main approaches to simulation were analyzed, and the scope of use of each of them was delineated. It was defined that computational fluid dynamics was the most used technique for reverse osmosis simulation; the intensive increase in using of molecular dynamics methods was pointed out. Since these two approaches provide the deepest insight into processes, it is likely that they will further be widely used for reverse osmosis simulations. At the same time, for the simulation of the membrane plant, it is reasonable to use the models that required the simplest solutions methods. The solution-diffusion model appears to be the most effective and flexible for these purposes. Therefore, this model was widely used in considering the period. The practical problems solved using each of the considered approaches were reviewed. Moreover, the software used for the solution of the mathematical models was regarded