Preparation and characterization of activated carbon from the char produced in the thermolysis of granulated scrap tyres

Abstract

The char produced in the thermolysis of granulated scrap tyres has few market outlets, reducing the economic viability of the thermolytic process. This paper reports the potential of this char as a low-cost precursor of porous carbons. The tyre-derived char was demineralized in either alkaline or acidic media to reduce its ash, zinc, sulfur, and silica contents. The lowest impurity content was achieved with an HNO 3 /H 2 O treatment. The resulting demineralized char was then subjected to activation by KOH or CO 2 . The Brunauer-Emmett-Teller (BET)-specific surface area of the activated carbon produced by the KOH treatment was 242 m 2 /g, whereas that of the CO 2 -activated carbon was 720 m 2 /g. The textural properties of the latter product were similar to those of some commercial activated carbons. The use of tyre-derived char as a precursor of porous carbons could render the thermolytic treatment of scrap tyres more economically attractive.Implications: Char produced in thermolysis of granulated scrap tyres has a few market outlets; in this paper an alternative for its use is presented. The char was converted into activated carbon with textural properties similar to those of some commercial activated carbons. This process could render the thermolytic treatment of scrap tyres more economically attractive.

Char from Spent Tire Rubber: A Potential Adsorbent of Remazol Yellow Dye

“…The XRD pattern (Figure 3) is typical of ST-derived chars, as the peaks observed were mainly attributed to zinc sulfide (ZnS) [25,31,32]. The ZnO used as accelerator in rubber vulcanization suffers sulfidation with the hydrogen sulfide (H2S) generated during ST rubber pyrolysis [33,34]. The mineral analysis of char (Table 2) revealed the presence of many metals and metalloids, but the high concentrations of zinc and silicon stood out.…”

Effect of pretreatment process on the characteristics of activated carbons produced from chemical activation of scrap tire

“…In another study, Lopez et al . studied the effect of alkaline or acidic demineralization prior to physical or chemical activation. The pretreatment with nitric acid was reported to yield the highest mineral elimination (∼73%) and active surface area compared to other tested acidic and alkaline environment.…”

“…Gupta et al [18] investigated the effect of microwave-assisted chemically pretreatment process on the conventional physical activation; the economic aspects of the synthesis were improved by achieving similar total pore volume and adsorption capacities of the ACs in shorter activation times. In another study, Lopez et al [19] studied the effect of alkaline or acidic demineralization prior to physical or chemical activation. The pretreatment with nitric acid was reported to yield the highest mineral elimination (73%) and active surface area compared to other tested acidic and alkaline environment.…”

Influence of process conditions on product yield of waste tyre pyrolysis- A review

“…The reaction between carbon black and agent generates gases by disintegration of carbon black particles, thereby increasing the surface area of carbon black. Table 9 presents properties of activated carbon [24,76,[78][79][80]. Activated carbons are mostly used as adsorbents to adsorb phenols, basic dyes, metals, p-chlorophenols, butane, natural gas, etc.…”