THE EFFECT OF H2SO4 HCL ON THE PHYSICO-CHEMICAL PROPERTIES OF KAOLIN CLAY(DUEKHLA SITE)

Abstract

This study discussed the physico-chemical properties of kaolin clay “Duekhlasite” after treating with inorganic acids(H2SO4, HCl)bystudying their effect on altering the chemical composition, the structure of the clay and on clayimpurities (Ironandtitaniumoxides), in which can be employed in thefuture in different industries such as in catalysts supports or as adsorbents. Raw kaolin was grinded to a particle size (-75micron) and treated with different concentrations ranging (2, 3, 4, 5, 6, 7, 8.5, 9.5) mol/l and (2, 3, 4, 5, 6, 7, 8.5, 9.5, 10.5, 11.5) mol/l of sulfuric acid and hydrochloric acid respectively, temperatures were studied at (90,100, 100ºC), Solid/Liquid (raw kaolin/acid solution) (1/8, 1/10, 1/12) and time of treatment 2and4 hrs. The treated and untreated samples were analyzed by XRF, XRD, and FTIR. After acid treatment, results from XRF and FTIR indicate that removal of octahedralcations; with other impurities (Al2O3, CaO, Na2O, K2O, MgO, Fe2O3, and TiO2) whileXRDstudies refer to the formation of an amorphous silica type phase. The chemical treatment increased Silica/Alumina ratio(Si/Al)that refers to information of amorphous silica was from1.23 in the raw to 15.13whensulfuric acid usedat treatment conditions (acid concentration 9.5M, S/L 1/8, temperature 100ºC, time 4hrs)while for hydrochloric acid Si/Albecame2.05 at conditions (acid concentration 11.5M,S/L 1/8,temperature 110ºC,time 4hrs), the surface area was increased from30.11m2/g inraw kaolin to 118.2m2/g and 59.76m2/g for H2SO4and HCl respectively.