The electroless plating of palladium and palladium alloy membranes is fast becoming an important and enabling technology. This is more so when juxtaposed with the rising demand for high purity hydrogen for applications particularly in proton exchange membrane fuel cells (PEMFC). The effect of process factors such as sensitization and activation during surface modification, concentration of the reducing agent, plating temperature, time, pH, additives, air aeration on plating efficiency, quality of the palladium film and deposit morphology is reviewed with the aim of identifying areas requiring further investigation. The paper also reviews how these process factors could be optimised for better plating efficiency and overall membrane quality. The concentration of the reducing agent has been identified as the limiting factor on plating efficiency albeit other process factors separately impact on the plating efficiency. Furthermore, bulk precipitation caused by concentration of the reducing agent has been identified as a major problem during electroless plating with hydrazine based plating baths. To ameliorate this problem, a multi step addition of the hydrazine reducer in separate portions has been recommended.

The spread of Diseases like Cholera and Diarrhea, which leads to loss of lives in developing countries is commonly caused by use of contaminated water. In this study ceramic pot filters for rural area water purification were developed. The clay sample was tested for physical properties and the mixtures of the clay and sawdust were made in seven (7) proportions of 75/25, 70/30, 65/35, 60/40, 55/45, 50/50, 45/55. The soil tests conducted on the different portions of the clay and sawdust material revealed that the shrinkage of the sawdust blended clay reduced to the minimum of 6.3 compared to the pure clay with 13.7. A fluid dynamic test experiment on each filter was conducted; similarly total dissolved solids (TDS), pH and turbidity tests for both raw water and filtered water were conducted. From fluid dynamic test results, filter 50/50 % tends to have higher filtration rate compared to the other two filters. From the TDS, pH, and turbidity test, the results obtained show that the filtered water quality has fallen within the world health organization (WHO) standard. It can therefore be concluded that the filtered water is safe for consumption.

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The main purpose of this work is to investigate the hydrogen permeation behavior of a commercial ceramic alumina membrane and compare same with that of a γalumina membrane graded with an AlOOH sol using the dip coating method. The permeance of hydrogen and 5 other single gases (He, N2, CH4, CO2 and Ar) were investigated at high temperatures. Mixed gas permeation tests for a H2 gas mixture were also carried out. Results show that the permeance of H2 increased

The mitigation of the CO inhibition effect in palladium membranes is necessary due to its significance in the efficiency of membrane reactors and hydrogen production systems. In this work, the hydrogen separation performance of a Pd and Pd/Ag membrane both of thickness 2 μm is investigated using a mixed gas with composition (H 2 = 50%, CO = 28%, CO 2 = 10%, CH 4 = 8%, N 2 = 4%) at temperature 623 -873 K and pressure (0.05 -0.4 bar) was investigated. The component gases CO and CO 2 were observed to inhibit hydrogen permeation through the membrane and lead to deviations from Sievert's law for n values 0.55 and 0.62 for the Pd membrane and unity for the Pd/Ag membrane.For the Pd/Ag membrane, the concentration of CO in the permeate stream was reduced as a result of the addition of Ag. The effect of the component gases to hydrogen permeation was observed to be lower for the Pd/Ag membrane. Annealing the membrane in hydrogen at high temperature decreased the inhibition effect and enhanced hydrogen permeation through the membrane.