Characterization of Biochar from Pyrolysis of Rice Husk and Rice Straw

Abstract

The valorization of rice husk biochar obtained by pyrolysis was studied by production high quality activated carbon. Activated carbon (AC) chemically treated by K 2 CO 3 , was used as sorbent phase in bar adsorptive microextraction followed by comprehensive two-dimensional gas chromatography coupled to a quadrupole mass spectrometer analysis (BAµE/GC×GC-qMS) for trace analysis of carbazole in commercial diesel. The prepared AC was characterized by N 2 adsorption, SEM-EDS and pH PZC. Assays of nitrogen adsorption isotherm demonstrated that the AC presented microporosity and the Density Functional Theory Calculation was applied to obtain information concerning the micropore size distribution. The BET surface area and total pore volume were 1850 m 2 g-1 and 0.83 cm 3 g-1 , respectively. AC from rice huskpyrolysis (RH) showed an acceptable adsorption capacity for Carbazole in diesel matrices allowed us to obtain average recoveries of 91.0 % and convenient analytical parameters. From the data obtained, the proposed methodology proved to be a suitable sorption-based static microextraction alternative for monitoring trace levels of carbazole in commercial diesel.

Effect of Temperature on the Structural and Physicochemical Properties of Biochar with Apple Tree Branches as Feedstock Material

“…CEC is an important property of biochar indicating the capacity of a biochar to adsorb cation nutrients [20]. In our study, the CEC for the generated biochars significantly decreased from 66.59 to 18.53 cmol·kg −1 when the pyrolysis temperature increased from 300 to 600 °C (Figure 2), which was consistent with previous study [44]. The shift in CEC may due to the reduction of functional groups and oxidation of aromatic C with temperature [34], which was well supported by the lower O/C ratio and our FTIR and Boehm titration results at higher temperature.…”

Study of the Effect of Pyrolysis Temperature on the Cd2+ Adsorption Characteristics of Biochar

“…Table 2 shows the biochar pH and elemental composition of both materials obtained at various pyrolysis temperatures. Between 300 • C and 700 • C, the pH of the rice-husk biochar increased from acidic (pH = 5.31) to strongly basic (pH = 9.42), which was consistent with previous studies (pH = 5.37-9.82) [16], while the pH of the cotton-straw biochar increased from neutral (pH = 6.61) to strongly basic (pH = 10.42). A previous study found that the pH of biochar typically ranges from 4 to 12 [17], and the results of the present study fell within that range.…”

Evaluation of the potential of feedstock combinations and their biochars for soil amendment

“…The factors affecting CEC include (a) surface structure, (b) surface area and (c) functional groups (such as phenolic, hydroxyl and carbonyl groups) (Claoston et al, 2014; Liang et al, 2006). As the pyrolysis temperature increased from 300°C to 500°C, the CEC decreased as reported by other studies (Phuong et al, 2015; Zhao et al, 2017). Numerous research works have reported the reduction of CEC with increasing temperature and pyrolysis (Claoston et al, 2014; Zornoza et al, 2016).…”