Microdurezza Rockwell:

I risultati del test di microdurezza Rockwell vengono sintetizzati in Tabella 6.9.

Tabella 6.9 – Microdurezza Rockwell.

HR30T 1050 °C 1100 °C Cab 70 79,9 94,2 TM-Cab 70 79,6 94,1 T-Cab 70 79,9 94,4 Lac Ben 70,0 83,7 TM-Lac Ben 69,8 83,7 T-Lac Ben 70,1 83,9 R3

Ba-Cab 70
93,7 Ba-Lac Ben

Ba-R3

K-Cab 70
86,0 K-Lac Ben 93,4 94,1 K-R3
59,1 C7+OR 55,3 72,3 Ba-C7+OR 51,7 71,9 R3+OR 52,1 71,3 Ba-R3+OR 54,4 72,0

Cab 70 presenta valori di microdurezza più elevati rispetto a Lac Ben. Entrambi i materiali, cotti alla temperatura di 1100 °C, fanno registrare

un sensibile aumento della microdurezza superficiale da mettere in relazione con l’aumento di densità.

La determinazione di tale parametro non è stata possibile per tutti i materiali poiché alcuni di essi hanno subito rottura durante l’esecuzione della prova.

Il processo di scambio cationico ha determinato differenti risposte da parte dei materiali trattati. Scambiando Lac Ben con potassio, si osserva un netto miglioramento di microdurezza da mettere in relazione con il comportamento fondente di questo catione che favorisce una migliore densificazione del materiale.

B

B

IIBBLLIIOOGGRRAAFFIIAA

Ames L.L.J. (1960) - The cationic sieve properties of Clinoptilolite. American Mineralogist, 45, 689-700.

Ames L.L.J., Mercer B.W. (1978) - Zeolite ion exchange in radioactive and municipal wastewater treatment. Natural Zeolites, Occurrence, Properties and Use, L.B. Sand F.A. Mumpton Eds., Pergamon Press, Oxford, 3-27.

Andreola F., Manfredini T., Passaglia E., Pellacani G.C., Pozzi P., Romagnoli M. (1994) - Utilization of an Italian Zeolite in ceramic bodies. Materials Engineering, 5 (2), 299-312.

ASTM C326 (1982) - Standard Test Method for Drying and Firing Shrinkages of Ceramic Whiteware Clays, 93-94.

ASTM C329 (1982) - Standard Test Method for Specific Gravity of Fired Ceramic Whiteware Materials, 95-96.

ASTM C373-88 (2005) - Standard Test Method for Water Adsorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products, 116-117.

Bish D.L., Chipera S.J. (1988) - Problems and solutions in quantitative analysis of complex mixture by X-ray powder diffraction. Adv. X-ray Analysis, 31, 295-307.

Breck D.W. (1974) - Zeolite Molecular Sieves. John Wiley & Sons Eds., New York.

Breck D.W. (1980) - Potential uses of natural and synthetic Zeolites in industry. Properties and Applications of Zeolites, R.P. Townsend ed., The Chem. Soc. London, 391-422.

Cappelletti P., Cerri G., Colella A., de’Gennaro M., Langella A., Perrotta A., Scarpati C. (2003) - Post-eruptive processes in the Campanian Ignimbrite. Mineralogy and Petrology, 79, 79- 97.

Cerri G., Cappelletti P., Langella A., de’Gennaro M. (2001) - Zeolitization of Oligo-Miocene volcanoclastic rocks from Logudoro (northern Sardinia, Italy). Contrib. Mineral. Petrol., 140, 404-421.

Cerri G., Mameli P., Oggiano G. (2003) - Determination of Illite / Smectite ratio in an interlayed clay mineral from the zeolitized epiclastic deposit of eastern Logudoro, Sardinia, Italy. Atti del Convegno GEOSED 2003, Alghero, 287-289.

Cerri G., Oggiano G. (2002) - Le epiclastiti zeolitizzate del Logudoro orientale: un livello guida all’interno della successione vulcano-sedimentaria della Sardegna centro-settentrionale. Boll. Soc. Geol. It., 121, 3-10.

Chipera S.J., Bish D.L. (1995) - Multireflection RIR and intensity normalizations for quantitative analyses: applications to Feldspars and Zeolites. Powder Diffraction, 10, 47-55. Chung F.H. (1974) - Quantitative interpretation of X-ray diffraction patterns of mixtures. Matrix-flushing method for quantitative multicomponent analyses. J. Appl. Cryst., 7, 519-525. Ciambelli P., De Simone V., Marino C. (1984) - Evaluation of Italian Zeolite tuff as adsorbent in oxygen enrichment of air. Annali di Chimica 74, Società Chimica Italiana, 18-29.

Chabazite. J. Therm. Anal., 47, 281-289.

Colella C., Aiello R., de’Gennaro M. (1987) - Ion exchange applications of Italian Zeolite tuff. Special Issue of Rend. Acc. Sc. Fis. Mat. in Napoli, 85-105.

Colella C., Aiello R., Nastro A. (1984) - Evaluation of Phillipsite tuff for the removal of ammonia from aquaculture wastewater. Use of Natural Zeolites in Agriculture and Aquaculture, W.G. Pond F.A. Mumpton Eds, Westiew Press Boulder, 239-244.

de Gennaro R., Cappelletti P., Cerri G., de’Gennaro M., Dondi M., Langella A. (2005) - Neapolitan Yellow Tuff as raw material for lightweight aggregates in lightweight structural concrete production. Applied Clay Science, 28, 309-319.

de Gennaro R., Dondi M., Cappelletti P., Cerri G., de’Gennaro M., Guarini G., Langella A., Parlato L., Zanelli C. (2007) - Zeolite-feldspar epiclastic rocks as flux in ceramic tile manufacturing. Microporous and Mesoporous Materials, 105, 273-278.

De Vivo B., Rolandi G., Gans P.B., Calvert A., Bohrson W.A., Spera F.J., Belkin H.E. (2001) - New constraints on the pyroclastic eruptive history of the Campanian volcanic plain (Italy). Mineralogy and Petrology, 73, 47-65.

de’Gennaro M. & Marone P. (eds.) (2006) - Atti del Convegno di presentazione dei risultati del Progetto Internazionale “Alta Formazione e Ricerca in Tema di Utilizzo degli Scarti dell’Industria Lapidea”, Napoli.

de’Gennaro M., Colella C., Aiello R., Franco E. (1984) - Italian Zeolites 2. Mineralogical and technical features of Campanian Tuff. Industrial Minerals, 204, 97-109.

Dell’Agli G., Ferone C., Mascolo G., Pansini M. (2000) - Dilatometric characterization of natural Phillipsite and Chabazite bearing materials. Natural Zeolites for the Third Millennium, C. Colella F.A. Mumpton Eds., Litografia editrice Alfredo De Frede, Napoli, 299-304.

Di Bartolomeo P., Dondi M., Marsigli M. (1994) - Use of zeolitic rocks in ceramic tile production. Tile & Brick Int., 12 (4), 311-316.

Flanigen E.M. (1983) - Absorption properties of molecular sieve zeolites. Zeo-Agriculture, Pond & Mumpton Ed., 55-68.

Franco E. (1974) - La zeolitizzazione naturale. Atti del Convegno Lincei 1975, 95-115.

Franzini M., Leoni L., Saitta M. (1972) - A simple method to evaluate the matrix effects in X- ray fluorescence analyses. X-ray spectr., 1, 151-154.

Gottardi G. (1978) - Mineralogy and crystal chemistry of Zeolites. Natural Zeolites, Occurrence, Properties and Use, L.B. Sand F.A. Mumpton Eds, Pergamon Press, Oxford, 31-34.

Hawkins D.B. (1981) - Kinetics of glass dissolution and Zeolite formation under hydrothermal conditions. Clays and Clay Minerals, 29, 331-340.

Hay R.L. (1966) - Zeolites and zeolitic reactions in sedimentary rocks. Geol. Soc. Am. Spec. Pap., 85, 130.

Hay R.L. (1978) - Geologic occurrence of Zeolites. Natural Zeolites, Occurrence, Properties and Use, L.B. Sand F.A. Mumpton Eds, Pergamon Press, New York, 135-145.

increasing yield of wheat. Natural Zeolites, Occurrence, Properties and Utilization, D. Kallo H.S. Sherry Eds., Budapest, 717-727.

Langella A., Cappelletti P., Cerri G., Bish D.L., de’Gennaro M. (1999) - Distribution of industrial minerals in Sardinia (Italy): Clinoptilolite bearing rocks of the Logudoro region. P. Misaelides F. Macasek T.J. Pinnavaia C. Colella Eds., Natural Microporous Materials in Environmental Technology, NATO Science Series E: Applied Sciences, 362, 237-252.

Langella A., De Simone P., Calcaterra D., Cappelletti P., de’Gennaro M. (2002) - Evidence of the relationship occurring between zeolitization and litification in the yellow facies of Campanian Ignimbrite (southern Italy). Studies in Surface Science and Catalysis, 142, 1775- 1782.

Langella A., Naimo D. (2003) - Influence of Zeolites on the sintering and technological properties of porcelain stoneware tiles. Journal of the European Ceramic Society, 23, 2237-2245. Langella A., Pansini M., Cerri G., Cappelletti P. & de’Gennaro M. (2003) - Thermal behaviour of natural and cation-exchanged Clinoptilolite from Sardinia (Italy). Clays and Clay Minerals, 51, 625-633.

Lenzi G., Cassano G. (1988) - The zeolitized tuffs of mount Vulture (Basilicata, Italy): Mineralogical and Physico-chemical study for use as decontaminants for radioactive solutions, in Occurrence, Properties and Utilization of Natural Zeolites, D. Kallò e H.S. Sherry Ed., Akademiai Kiadò, Budapest, 803-819.

Leoni L., Saitta M. (1976) - X-ray fluorescence analysis of 29 trace elements in rock and mineral standards. Rendiconti Società Italiana di Mineralogia e Petrologia 32, 497-510.

Meier W.M. (1968) - Zeolite structures. Molecular Sieves, Soc. Chem. Ind., Londra 10-27. Minato H., Tamura T. (1978) - Production of oxigen and nitrogen with natural zeolites, in Natural Zeolites: Occurrence, Properties and Use, L.B. Sand, F.A. Mumpton Eds., Pergamon Press New York 509-513.

Mumpton F.A. (1973) - Worldwide deposits and utilizzation of natural zeolites. Industrial Minerals, 73 30-45.

Mumpton F.A. (1978) - Natural zeolites: a new industrial mineral commodity: in Natural Zeolites: Occurance, Properties, Use, L.B. Sand and F.A. Mumpton eds, Pergamon Press, Elmsford, N.Y.,3-27.

Mumpton F.A. (1984) - The role of natural zeolites in agriculture and acquaculture, in Zeo- Agriculture. Use of Natural Zeolites in Agriculture and Acquaculture, W.G. Pond, F.A. Mumpton Eds. Westwiew Press,Boulder 3-29.

Mumpton F.A. (1985) - Development of uses for natural zeolites: a critical commentary. Procedings of “Zeolite 85”. An. Int. Cof. on the Occurrence, Properties, and Utilization of Natural Zeolites, Budapest 1985, 333-367.

Oggiano G., Funedda A., Pasci S. (1995) - Il Bacino di Chillivani-Berchidda: un esempio di struttura transtensiva. Possibili relazioni con la geodinamica Cenozoica del Mediterraneo occidentale. Boll. Soc. Geol. It., 114, 465-475.

Passaglia E., Vezzalini G., Carnevali R. (1990) - Diagenetic Chabazites and Phillipsites in Italy: crystal chemistry and genesis. Eur. J. Mineral, 2, 827-839.

Pond W.G., Jong-Tseng Yen (1984) - Physiological effects of Clinoptilolite and synthetic zeolite A in animals, in Zeo-Agriculture. Use of Natural zeolites in Agriculture and Acquaculture, W. G. Pond, F.A. Mumpton Eds., Westwiew Press, Boulder 127-142.

Prieto-Valdés J.J., Victorero-Rodriguez A., Mir-Caraballo M., Rodriguez-Fuentes G. (1991) - Natural Zeolites for Ceramic Industry. In "Zeolite '91" Int. Conf. On Occurrence, Properties and Utilization of Natural Zeolites. 130-137.

Prieto-Valdés J.J., Victorero-Rodriguez, A. (1992) - Ceramic material from zeolite rock: structure and properties. J. Materials Science Letters, 11, 678-680.

Scherillo A. (1955) - Petrografia chimica dei Tufi Flegrei II, Tufo Giallo, Mappamonte, Pozzolana. Rend.Acc.Sc.Fis.Mat. (Naples) 22, 345-370.

Sersale R. (1985) - Natural zeolites: processing present and possible applications. Zeolites. Synthesis, Structure, Technology and applications. B. Drzay, S. Horevar, S. Pejovkin, Eds, Elsevier, Amsterdam 503-512.

Sistu G. (1990) - Materiali alternativi per impasti ceramici: le piroclastiti del vulcanismo terziario della Sardegna. Ceramurgia, 20, 107-113.

Tchernev D.L. (1980) - The use of zeolites in solar cooling. Proc. 5th. Int. Conf. Zeolites Naples 1980, L.V.C. Rees,ed.Heyden, London, 788-794.