Influence of Addition of Rice Husk Ash on Porcelain Composition

Rice husk ash (RHA) has long been known to possess high silica content. The abundance of rice husk as agricultural waste makes it the most promising to be used as a supplementary cementations and ceramic material. In this study RHA was used as an additive material on porcelain body. The rice husk was subjected to the chemical pretreatment with 2M HCL, 250C before calcinations to increase silica content of the husk ash. The pressed pellets were sintered at the temperature of 12000C and soaked for 2 hours. It was found that progressive addition of RHA in a porcelain body resulted in early vitrification of the mixture. The compressive strength was the highest at 40wt% addition of RHA. Porosity was the least at 40wt%. It can therefore be concluded that 40wt% addition of RHA into the porcelain body is the best composition.Keywords: RHA, Porcelain, Compressive Strength, Bulk Density, Porosit

Influence of Mould Pressure and Substitution of Quartz by Palm Oil Fuel Ash on the Hardness of Porcelain Body

This paper presents use of treated palm oil fuel ash (POFA) as a substitute material for quartz in fabricating an improved porcelain tile. Untreated POFA was dried in an oven at 100ºC for 24 h. The untreated POFA was then grounded in a ball mill to reduce the particle size to improve reactivity. It was then sieved using a set of sieves (50 μm) to remove the particles coarser than 50 μm. The untreated POFA was heated at a temperature of 600 ºC for 1.5 h. The mixed powder was pressed into pellets at pressure of 31MPa, 61 MPa, 91 MPa and 121 MPa. All the pellets were sintered at a temperature of 1100 ºC for 2 h soaking time. It was found that the bulk density and Vickers hardness of porcelain increases with increase in substitution of quartz by POFA. The highest bulk density and Vickers hardness of the porcelain was achieved on 15 wt% substitution of quartz by POFA at a Mould pressure of 91 MPa.Keywords: Bulk Density, POFA, Porcelain, Porosity, Volume Shrinkage, Quart

Nuclear and Atomic Methods Applied in the Determination of Some Heavy Polluting Elements in Some Soil Samples around Industrial Locations in Kano-Nigeria

Heavy metals (HM) can have a serious impact if released into environment even in trace quantities. These can enter into food chain from aquatic and agricultural ecosystems and threaten human health indirectly. An experiment was carried out to investigate some heavy elements from soil samples of different industrial locations of Kano state, Nigeria. The techniques used were Neutron Activation Analysis (NAA) and Atomic Absorption Spectrometry (AAS). The order of average contents of metals in soil samples was Mn>Fe>Zn>Cu>Pb>Cd>Cr>Ni and their concentration values ranged from (31.8 to 18.1), (21.1 to 10.3), (8.8 to 2.01), (7.17 to 1.72), (4.02 to 1.71), (2.18 to 0.19), (1.71 to 0.22) and (0.28 to 0.21) mg/kg, respectively. The results also indicated that Fe contents are higher than for Pb in each location and the two different techniques have shown good agreement with each other. The concentrations are within acceptable limits.Keywords: Heavy Metals, Neutron Activation Analysis, Atomic Absorption Spectrometry, Soil Sample