4Astm C 618 - 94a, Standard specification for coal fly ash and Raw or calcined natural pozzolan for use as a mineral admixture in portland cement concret.
5Tanaka H, Sakai Y, Hino R, Formation of Na- A and - X zeolites from waste solutions in conversion of coal fly ash to zeolites, Materials Research Bulletin,2002(37) : 1 873 - 1 884.
6Holler H, Wirsching U. Zeolite formation from fly ash.Fortschriue der Mineralogie, 1985,63(1) :21 - 27.
7Querol X,Umana J C,Plana F et al. Synthesis of zeolites from fly ash at pilot plant scale, example of potential applications.Fuel,2(1)2(80) :857 - 865.
8Mondragon R F. New perspectives for coal ash utilization: synthesis of zeolitic materials. Fuel, 1990,69(2) : 263 - 266.
9Querol X,Alastuey A, Lopez- Soler A et al.A fast method for recycling fly ash: microwave - assisted zeolite synthesis. Environ. Sci. Technol, 1997(31 ) : 2 527 - 2 533.
10Hollman G G, Steenbruggen G, Janssen- Jurkovicova M. A twostep process for the synthesis of zeolites ftmu coal fly ash.Fuel, 1999(78) : 1 225- 1 230.