Application of Graphitic Bio-Carbon using Two-Level Factorial Design for Microwave-assisted Carbonization

Abstract

A novel intermittent microwave-assisted carbonization method was developed to prepare bio-char (BWSC) from Durian wood sawdust (BWS). The BWS was further activated using a base-catalytic approach to produce a graphitic form of bio-carbon (BWSAC). A three factor, twolevel central composite (CCD) experimental design was used to maximize Pb(II) ion removal from aqueous solution using BWSAC. Three independent variables (initial pH of solution (pH0) ranging from 2 to 8, initial metal ion concentration of Pb(II) cations (C0) ranging from 50 to 100 mg/L, and contact time (Ct) ranging from 10 to 300 min) were consecutively coded as x1, x2, and x3 at three levels (−1, 0 and 1) of the design matrix. The experimental conditions in terms of actual factors were determined to be x1 (pH0) = 5.86, x2 (C0) = 57.77 mg/L, and x3 (temperature) = 53.85 °C, and the resultant Pb(II) ion removal efficiency (y1) obtained was 92.73%, with a model desirability of 0.974. The change in physiochemical properties after carbonization as well as activation was observed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer, Emmett and Teller surface area analysis (BET), Thermogravimetric analysis (TGA), Ultimate analysis, and Fourier transform infrared spectroscopy (FTIR) .

The Effects of Pre-treatments and Low-temperature Pyrolysis on Surface Properties of Biochar from Sunflower Straw as Adsorption Material

“…This suggests that the crystalline structures of the prepared biochar changed after treatment with KOH and H3PO4. The crystalline index of the samples are given in Table 1 (Chowdhury et al 2016c). …”

Poly(amidoxime) from Polymer-Grafted Khaya Cellulose: An Excellent Medium for the Removal of Transition Metal Cations from Aqueous Solution

“…Pollution of aquatic streams by heavy metals causes severe environmental problems because of their toxic and carcinogenic effects (Mance 1987;Nriagu and Pacyna 1988;Liu et al 2008;Chowdhury et al 2016b). Heavy metals are commonly discharged into the environment from mining activities, fossil fuels, battery manufacturing, automobile emissions (Ozay et al 2009), metal plating, or electric device fabrication (Denizli et al 2005).…”

Adsorption Studies of Volatile Organic Compound (Naphthalene) from Aqueous Effluents: Chemical Activation Process Using Weak Lewis Acid, Equilibrium Kinetics and Isotherm Modelling

“…Adsorption kinetics can provide information regarding the rate of reaction at a constant pressure or temperature [ 38 , 39 ]. Linear plots for pseudo-first and second order kinetics for naphthalene (C 10 H 8 ) adsorption over DSP and CDSP are shown in Figure 2 and Figure 3 .…”

“…Furthermore, the experimental q e obtained for this model was nearly equivalent with the calculated q e values after linearization ( Table 3 ). This reflected that, over the CDSP sample, the adsorption process of C 10 H 8 proceeded via chemical interactions mainly [ 10 , 37 , 38 , 39 ]. On the contrary, C 10 H 8 adsorption onto the unactivated, raw DSP sample by the pseudo-first order model also showed better linearity, except concentrations 25 and 37.5 ppb ( Table 2 ).…”