Copper(II) ion removal by chemically and physically modified sawdust biochar

Abstract The difference between physical activations (by sonications) and chemical ammonia) on sawdust biochar has been investigated in this study by comparing the removal of Cu(II) ions from an aqueous medium adsorption (SD), sonicated (SSD), ammonia-modified (SDA) with stirring at room temperature, pH value 5.5–6.0, 200 rpm. was prepared dehydrations wood reflux sulfuric acid, formed activated physically sonications chemically ammonia solutions then characterized Fourier transform infrared (FTIR); Brunauer, Emmett, Teller (BET); scanning electron microscope (SEM); thermal gravimetric analysis (TGA); energy-dispersive spectroscopy (EDX) analyses. involves 100 mL sample volume initial ion concentrations (conc) 50, 75, 100, 125, 150, 175, mg L −1 doses 200, 250, 300 mg. maximum percentage 95.56, 96.67, 98.33% for SD, SSD, SDA biochars, respectively, 50 conc 1.0 g adsorbent dose. correlation coefficient ( R 2 ) used to confirm data obtained isotherm models. Langmuir model best fitted experimental SDA. capacities Q m are 91.74, 112.36, 133.33 , respectively. degree fitting using non-linear models sequence (LNR) (ideal fit) > Freundlich (FRH) Temkin (SD SSD) FRH LNR (SDA). ideally described biosorption SD SSD owing low values χ rate well-ordered pseudo-second-order (PSO) Finally, modified enhances ions’ efficiency more than (SSD). Response surface methodology (RSM) optimization studied biochars.