dingxinda Yeni Üye

Kayıt Tarihi: 2021-13-Ocak
Aktif Durum: Pasif Gönderilenler: 30
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Gönderen: 2021-18-Ocak Saat 05:27 | Kayıtlı IP
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Indispensable role of inherent calcite in coal on
activated carbon (AC)’s preparation and applications
Calcite (CaCO3) is the main calcium-containing mineral in
coal,
www.coalactivat
edcarbon.com activated carbons (ACs) were obtained
through blending Alxa coal with different content of
CaCO3 (2, 4, 6, 8%), molding, carbonization at 600 °C
and activation at 900 °C under water–vapor atmosphere.
As-derived ACs were investigated physiochemical structure
and performance by XRD, SEM, BET, XPS, SO2 and rhodamine-
B (RhB) removal test. The results show that: (1) CaCO3
promotes the development of AC’s physiochemical
structure and surface chemistry. CaCO3 is beneficial to
pore evolution through etching carbon surface, which
causing the evolution of micropore/mesopore to
mesopore/macropore and/or pores collapse. The total
specific surface area and micropore’s specific surface
area has decreased from 895 m2/g and 674 m2/g to 671 m2/g
and 564 m2/g with CaCO3 addition up to 8%. The total
volumes and micropore’s volumes (<2 nm) also decreased
from 0.40 cm3/g and 0.33 cm3/g to 0.31 cm3/g and 0.24
cm3/g, respectively. The O/C and π-π* are increased
linearly with the addition CaCO3; (2) CaCO3’s addition
promotes sulfur capacity through enhancement of pore
structure, oxygen-containing functional groups and π-
π*. Moreover, the CaO in ACs participates in the
desulfurization process and finally forms CaSO4, which
further promotes desulfurization, and the mechanism was
proposed; (3) CaCO3’s addition slightly decrease the RhB
adsorption capacity from 96.7 mg/g to 87.9 mg/g due to
competition of OH− with COO−.activated-carbon.com/">wholesale activated carbon
The results of this work indicate that AC prepared from
high-calcium coal is more suitable for desulfurization
other than RhB removal.
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