Preparation and Adsorption Performance of Fly Ash Based Porous Ceramics

Abstract

Abstract: The effective utilization of fly ash based porous ceramics can not only reduce the pollution of fly ash to the environment but also show high application value in wastewater treatment and other fields. In this paper, porous ceramics with excellent performance were prepared by direct molding sintering method with fly ash as the main raw material, bentonite as the binder and activated carbon as the pore forming agent. The effects of sintering temperature and activated carbon amount on the structures and properties of porous ceramics were studied. The results show that sintering fly ash and bentonite forms the porous ceramic skeleton, oxidized activated carbon forms the pores, and porous ceramics are formed under their synergetic effects. At the same time, with the increase of sintering temperature and the decrease of activated carbon amount, the apparent porosity and water absorption decrease, the bulk density and compressive strength increase. When the sintering temperature is 1 100 ℃ and the amount of the activated carbon is 60% (mass fraction), the prepared porous ceramics with good comprehensive performance can be prepared. Its apparent porosity is 61.75%, bulk density is 0.93 g·cm^-3, water absorption is 63.48%, compressive strength is 4.29 MPa. Moreover, its removal rate is 98.4% and the saturated adsorption capacity is 45.79 mg·g^-1 in the Pb²⁺ solution of 100 mg·L^-1.

Key words: fly ash, activated carbon, porous ceramics, Pb²⁺, removal rate, adsorption capacity

CLC Number:

TQ174

BAI Lizhong, WANG Chaonan, CHENG Jun, ZHAO Zitong, GENG Jiawang, LI Xuefeng. Preparation and Adsorption Performance of Fly Ash Based Porous Ceramics[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(11): 4122-4130.

References

[1] BHATT A, PRIYADARSHINI S, MOHANAKRISHNAN A A, et al. Physical, chemical, and geotechnical properties of coal fly ash: a global review[J]. Case Studies in Construction Materials, 2019, 11: e00263.
[2] WANG C, XU G G, GU X Y, et al. High value-added applications of coal fly ash in the form of porous materials: a review[J]. Ceramics International, 2021, 47(16): 22302-22315.
[3] YIN Y, MA B Y, LI S M, et al. Synthesis of Al₂O₃-SiC composite powders from coal ash in NaCl-KCl molten salts medium[J]. Ceramics International, 2016, 42(16): 19225-19230.
[4] MA B Y, REN X M, YIN Y, et al. Effects of processing parameters and rare earths additions on preparation of Al₂O₃-SiC composite powders from coal ash[J]. Ceramics International, 2017, 43(15): 11830-11837.
[5] MA B Y, SU C, REN X M, et al. Preparation and properties of porous mullite ceramics with high-closed porosity and high strength from fly ash via reaction synthesis process[J]. Journal of Alloys and Compounds, 2019, 803: 981-991.
[6] LIU J, DONG Y C, DONG X F, et al. Feasible recycling of industrial waste coal fly ash for preparation of anorthite-cordierite based porous ceramic membrane supports with addition of dolomite[J]. Journal of the European Ceramic Society, 2016, 36(4): 1059-1071.
[7] ZHAO H, WANG P Y, YU J L, et al. A mechanistic study on the synthesis of β-SiAlON whiskers from coal fly ash[J]. Materials Research Bulletin, 2015, 65: 47-52.
[8] VAKIFAHMETOGLU C, ZEYDANLI D, COLOMBO P. Porous polymer derived ceramics[J]. Materials Science and Engineering: R: Reports, 2016, 106: 1-30.
[9] DZMITRY M, KLIMENTY B. A porous materials production with an electric discharge sintering[J]. International Journal of Refractory Metals and Hard Materials, 2016, 59: 67-77.
[10] MA B Y, LI Y, LIU G Q, et al. Preparation and properties of Al₂O₃-MgAl₂O₄ ceramic foams[J]. Ceramics International, 2015, 41(2): 3237-3244.
[11] GE H B, WANG G, YUAN B, et al. Fabrication and microstructure of porous SiC ceramics using suspension emulsions as pore-forming agents[J]. Ceramics International, 2014, 40(8): 11705-11711.
[12] YUAN L, MA B Y, ZHU Q, et al. Preparation and properties of mullite-bonded porous fibrous mullite ceramics by an epoxy resin gel-casting process[J]. Ceramics International, 2017, 43(7): 5478-5483.
[13] DENG X G, WANG J K, LIU J H, et al. Low cost foam-gelcasting preparation and characterization of porous magnesium aluminate spinel (MgAl₂O₄) ceramics[J]. Ceramics International, 2016, 42(16): 18215-18222.
[14] KAN X Q, DING J, YU C, et al. Low-temperature fabrication of porous ZrC/C composite material from molten salts[J]. Ceramics International, 2017, 43(8): 6377-6384.
[15] YOU Q W, LIU Y S, WAN J J, et al. Microstructure and properties of porous SiC ceramics by LPCVI technique regulation[J]. Ceramics International, 2017, 43(15): 11855-11863.
[16] HWA L C, RAJOO S, NOOR A M, et al. Recent advances in 3D printing of porous ceramics: a review[J]. Current Opinion in Solid State and Materials Science, 2017, 21(6): 323-347.
[17] DANG W, WANG W H, WU P F, et al. Freeze-cast porous Al₂O₃ ceramics strengthened by up to 80% ceramics fibers[J]. Ceramics International, 2022, 48(7): 9835-9841.
[18] CHATHURAPPAN R, JAYAPAL A. Synthesis and characterization of coal fly ash based multipurpose ultrafiltration membrane[J]. Materialia, 2022, 25: 101548.
[19] LIU T Y, TANG Y, HAN L, et al. Recycling of harmful waste lead-zinc mine tailings and fly ash for preparation of inorganic porous ceramics[J]. Ceramics International, 2017, 43(6): 4910-4918.
[20] AL-QADHI E, LI G Y, NI Y X. Influence of a two-stage sintering process on characteristics of porous ceramics produced with sewage sludge and coal ash as low-cost raw materials[J]. Advances in Materials Science and Engineering, 2019, 2019: 1-12.
[21] MIAO Q D, ZHANG Z S, XIA J P. Preparation of low-temperature ceramic foam material with fly ash[J]. Bulletin of the Chinese Ceramic Society, 2010, 29(6): 1463-1467.
[22] SHEN J J, XUE Q H, LIU Y J, et al. Optimization for the manufacturing process of fly ash foamed ceramics[J]. Bulletin of the Chinese Ceramic Society, 2016, 35(2): 617-622.
[23] ZHANG F, NIU H H, LI W, et al. Investigation on the manufacturing process and properties of ceramic wall brick and floor tile with fly ash[J]. Bulletin of the Chinese Ceramic Society, 2018, 37(6): 1941-1945.