Korean Journal of Chemical Engineering, Vol.36, No.7, 1164-1171, July, 2019
Robust synthesis of coal bottom ash-based geopolymers using additional microwave heating and curing for high compressive strength properties
E-mail:
While coal bottom ash (CBA) contains an amount of amorphous silica and alumina as high as coal fly ash (CFA), its irregular particle shapes and excess unburnt carbon content compared to CFA are known to decrease the compressive strength of CBA-based geopolymers. Hence, we propose an advanced synthetic method of high-strength CBA-based geopolymer by appending microwave heating to conventional oven curing process without pretreatments for carbon removal. First, we blended finely crushed CBA with a moderate amount of 14M NaOH alkali activator to make a mixture in a slightly wet state. Then, we fabricated precast samples by casting the mixture against 5-cm cubic molds with the help of a hand press. Next, the samples were hardened through the two-stage process of pre-dry-oven curing (12, 24 and 36 hr at 75 °C) and post-microwave-oven heating (up to 7min under 700 W power). In essence, the specimens cured for 36 hr in the dry oven showed a considerable improvement in compressive strength just after being heated for 3min in the microwave oven (from 12.8 to 40.5MPa). This newly proposed synthetic method is proven to be very cost-effective for producing CBA-based geopolymer with high compressive strength.
Keywords:Coal Bottom Ash-based Geopolymers;Compressive Strength;Slightly Wet State;Microwave;Cost-effective Technique
- Ramme BW, Tharaniyil MP, We energies coal combustion products utilization handbook (3rd Ed.), We Energies Publication, Wisconsin (2013).
- American Road and Transportation Builders Association (ARTBA), market forecast through 2033 (Published in Jun., 2015).
- Kalyoncu RS, Olson DW, Coal combustion products, (published in Aug., 2001) (Retrieved on Aug. 27, 2018 from https://pubs.usgs.gov/fs/fs076-01/fs076-01.pdf)..
- Yao ZT, Ji XS, Sarker PK, Tang JH, Ge LQ, Xia MS, Xi YQ, Earth-Sci. Rev., 141, 105 (2015)
- Jayaranjan MLD, Van Hullebusch ED, Annachhatre AP, Rev. Environ. Sci. Bio/Technol., 13(4), 467 (2014)
- Palomo A, Grutzeck MW, Blanco MT, Cem. Concr. Res., 29(8), 1323 (1999)
- Fernandez-Jimenez A, Palomo A, Fuel, 82(18), 2259 (2003)
- Fernandez-Jimenez A, Palomo A, Sobrados I, Sanz J, Microporous Mesoporous Mater., 91(1-3), 111 (2006)
- VanJaarsveld JGS, VanDeventer JSJ, Lorenzen L, Miner. Eng., 10(7), 659 (1997)
- Davidovits J, J. Mater. Educ., 16(2,3), 91 (1994)
- Chindaprasirt P, Jaturapitakkul C, Chalee W, Rattanasak U, Waste Manage., 29(2), 539 (2009)
- Van Jaarsveld JGS, Van Deventer JSJ, Schwartzman A, Miner. Eng., 12(1), 75 (1999)
- Kim H, Lee JY, World Coal Ash, Conf. Proc. (2017).
- Lee S, Seo MD, Kim YJ, Park HH, Kim TN, Hwang Y, Cho SB, Int. J. Miner. Process., 97(1-4), 20 (2010)
- Aunsholt KEH, US Patent, 4,426,282 (1984).
- Cochran JW, Kirkconnell SF, US Patent, 5,399,194 (1995).
- Nelson RD, Heavilon JL, Styron RW, Fletcher BG, US Patent, 5,299,692 (1994).
- Gray ML, Champagne KJ, Finseth DH, US Patent, 6,126,014 (2000).
- Kim H, Hong S, World Coal Ash, Conf. Proc. (2017).
- Somaratna J, Ravikumar D, Neithalath N, Cem. Concr. Res., 40(12), 1688 (2010)
- Chindaprasirt P, Rattanasak U, Taebuanhuad S, Adv. Powder Technol., 24(3), 703 (2013)
- Zuhua Z, Xiao Y, Huajun Z, Yue C, Appl. Clay Sci., 43(2), 218 (2009)
- Hardjito D, Wallah SE, Sumajouw DMJ, Rangan BV, Civil Eng. Dimension, 6(2), 88 (2004)
- Barbosa VFF, MacKenzie KJD, Thaumaturgo C, Int. J. Inorg. Mater., 2(4), 309
- Topcu IB, Toprak MU, Uygunoglu T, J. Clean Prod., 81, 211 (2014)
- Slavik R, Bednarik V, Vondruska M, Nemec A, J. Mater. Process. Technol., 200(1-3), 265 (2008)
- Hardjito D, Wallah SE, Sumajouw DMJ, Rangan BV, ACI Mater. J.
- Swanepoel JC, Strydom CA, Appl. Geochem., 17(8), 1143 (2002)
- Chindaprasirt P, Chareerat T, Sirivivatnanon V, Cem. Concr. Compos., 29(3), 224 (2007)
- Davidovits J, Geopolymer chemistry and applications (4th Ed.), Geopolymer Institute, France (2015).
- Xie J, Kayali O, Constr. Build. Mater., 67, 20 (2014)
- Gubb TA, Baranova I, Allan SM, Fall ML, Shulman HS, Kriven WM, Developments in Strategic Materials and Computational Design II, Wiley, New Jersey, 35 (2011).
- Hong S, Kim H, Poster session presented at the Fall Symposium of The Korean Inst. Chem. Eng., Korea (2018).
- Abdulkareem OA, Bakri AMMA, Kamarudin H, Nizar IK, Saif AA, Constr. Build. Mater., 50, 377 (2014)
- Zhang HY, Kodur V, Qi SL, Cao L, Wu B, Constr. Build. Mater., 55, 38 (2014)
- Duxson P, Provis JL, Lukey GC, Mallicoat SW, Kriven WM, Van Deventer JSJ, Colloids Surf. A: Physicochem. Eng. Asp., 269(1-3), 47 (2005)
- Provis JL, Van Deventer JSJ, Geopolymers, Woodhead Publishing, UK (2009).
- Phair JW, Van Deventer JSJ, Int. J. Miner. Process., 66(1-4), 121 (2002)
- Clayden NJ, Esposito S, Aronne A, Pernice P, J. Non-Cryst. Solids, 258(1-3), 11 (1999)
- Criado M, Fernandez-Jimenez A, Palomo A, Microporous Mesoporous Mater., 106(1-3), 180 (2007)
- Lee WKW, van Deventer JSJ, Langmuir, 19(21), 8726 (2003)
- Fernandez-Jimenez A, Palomo A, Criado M, Cem. Concr. Res., 35, 1204 (2005)
- Institute of Chemistry University of Tartu (Na2CO3) (Published on Dec. 7, 2015)(Retrieved on Jul. 18, 2018 from http://lisa.chem.ut.ee/IR_spectra/paint/fillers/1472-2/).