RESEARCH ARTICLE Fabrication and characterization of 3,4-diaminobenzophenone-functionalized magnetic nanoadsorbent with enhanced VOC adsorption and desorption capacity Ömer Şahin 1 & Sinan Kutluay 1 & Sabit Horoz 2 & Mehmet Şakir Ece 3 Received: 29 April 2020 /Accepted: 15 September 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract The present study, for the first time, utilized 3,4-diaminobenzophenone (DABP)-functionalized Fe 3 O 4 /AC@SiO 2 (Fe 3 O 4 / AC@SiO 2 @DABP) magnetic nanoparticles (MNPs) synthesized as a nanoadsorbent for enhancing adsorption and desorption capacity of gaseous benzene and toluene as volatile organic compounds (VOCs). The Fe 3 O 4 /AC@SiO 2 @DABP MNPs used in adsorption and desorption of benzene and toluene were synthesized by the co-precipitation and sol-gel methods. The synthesized MNPs were charac- terized by SEM, FTIR, TGA/DTA, and BET surface area analysis. Moreover, the optimization of the process parameters, namely contact time, initial VOC concentration, and temperature, was performed by applying response surface methodology (RSM). Adsorption results demonstrated that the Fe 3 O 4 /AC@SiO 2 @DABP MNPs had excellent adsorption capacity. The maximum adsorption capacities for benzene and toluene were found as 530.99 and 666.00 mg/g, respectively, under optimum process parameters (contact time 55.47 min, initial benzene concentration 17.57 ppm, and temperature 29.09 °C; and contact time 57.54 min, initial toluene concentration 17.83 ppm, and temperature 27.93 °C for benzene and toluene, respectively). In addition to the distinctive adsorptive behavior, the Fe 3 O 4 /AC@SiO 2 @DABP MNPs exhibited a high reproducibility adsorption and desorption capacity. After the fifth adsorption and desorption cycles, the Fe 3 O 4 /AC@SiO 2 @DABP MNPs retained 94.4% and 95.4% of its initial adsorption capacity for benzene and toluene, respectively. Kinetic and isotherm findings suggested that the adsorption mechanisms of benzene and toluene on the Fe 3 O 4 / AC@SiO 2 @DABP MNPs were physical processes. The results indicated that the successfully synthesized Fe 3 O 4 /AC@SiO 2 @DABP MNPs can be applied as an attractive, highly effective, reusable, and cost-effective adsorbent for the adsorption of VOC pollutants. Keywords Adsorption and desorption . Magnetic nanoparticles (MNPs) . Nanoadsorbents . Modeling . Volatile organic compounds (VOCs) Highlights • The novel Fe 3 O 4 /AC@SiO 2 @DABP MNPs were successfully synthesized, characterized, and used for enhancing VOC adsorption and desorption capacity. • Adsorption optimization of benzene and toluene VOCs was performed by applying RSM. • The maximum adsorption capacity of Fe 3 O 4 /AC@SiO 2 @DABP MNPs for benzene and toluene reached 531 and 666 mg/g, respectively. • Kinetic and isothermal model parameters were determined for the adsorption of VOCs. • The reusability performance of Fe 3 O 4 /AC@SiO 2 @DABP MNPs was studied for the adsorption and desorption of VOCs. Responsible editor: Tito Roberto Cadaval Jr * Mehmet Şakir Ece sakirece@artuklu.edu.tr 1 Department of Chemical Engineering, Siirt University, 56100 Siirt, Turkey 2 Department of Electrical & Electronics Engineering, Siirt University, 56100 Siirt, Turkey 3 Vocational High School of Health Services, Mardin Artuklu University, 47100 Mardin, Turkey Environmental Science and Pollution Research https://doi.org/10.1007/s11356-020-10885-y