Microporous Erionite-activated Carbon Composite From Oil Palm Ash for Doxycycline Antibiotic Removal

Microporous erionite-activated carbon (E-AC) composite was synthesized by activating oil palm ash followed by reacting with aluminum oxide (Al2O3) under alkaline conditions using hydrothermal method. The Al2O3 was added to the activated palm ash to balance the excess silica dioxide (SiO2) to obtain the erionite type of zeolite. The E-AC composite was employed to remove a potent pharmaceutical water pollutant, doxycycline antibiotic under batch adsorption. The effect of solution pH (3-13), doxycycline initial concentration, and temperature were screened in the batch study. The E-AC composite revealed appreciable surface area and average pore size of 467.23 m(2)/g and 2.765 nm, respectively, with abundant chemical surface hydroxyl (-OH) and amine (N-H) adsorptive sites. The textural and surface chemistry greatly contributed to a high monolayer adsorption capacity of 353.81 mg/g at 50 degrees C. Also, the Langmuir isotherm with a high R-2 of 0.99 for doxycycline adsorption on E-AC sufficiently described the equilibrium data. High monolayer adsorption capacity of E-AC compared to other adsorbents in the literature suggests the efficiency of this study. Novel composite synthesis was aimed to enhance the surface area and to increase the doxycycline removal capacity. These encouraging results show that the E-AC composite could pave the way for more low-cost composites to be used as adsorbents for pharmaceutical and other pollutant removals from wastewater.

Automated summary

The microporous erionite-activated carbon (E-AC) composite showed promising potential in removing the doxycycline antibiotic from water, with high monolayer adsorption capacity and efficient removal efficiency. The novel composite synthesis aimed to enhance surface area and increase pollutant removal capacity, paving the way for more cost-effective adsorbents in wastewater treatment.