Benzene is harmful both to living organisms and the environment and should, therefore, be extracted from water. Phosphoric acid and activated carbon from the rice husk are used in this process. A rapid intake of benzene was observed. A thorough analysis of kinetic data using various techniques proved that the data fitted in pseudo-second order models. The results point to the fact that chemisorption took place. Additionally, rice husks were found to have better benzene adsorption capacity compared to other adsorbents.
Who did the research and where? The study was conducted in Egypt where the rice husks were locally available. Students from the King Saud University were responsible for carrying out the research.
How was the research conducted and with what materials and methods (experimentally or otherwise)? The study was conducted experimentally. The main materials used were rice husks and n=benzene. Rice hulls were obtained locally and their dimensions measured and recorded. A kinetic study was carried out based on the plotted adsorption profile. Techniques such as pseudo first-order, pseudo second-order, and the Elovich kinetic equation models were employed in the kinetic study. Informed judgment was passed based on a comparison between the experimental and theoretical values.
What were the results of the research? Single curves were obtained. These were smooth and continuous, and they led to saturation were obtained. Figures of the uptake of benzene indicate a quick uptake between zero to thirty minutes. The absorption rate slowly decreases up to the fortieth minute with no indication of uptake after that point.
How were they interpreted? The curves obtained signify possible monolayer benzene coverage on the surface of the rice husks. The curves also indicate that benzene absorption increases with time until it reaches a point of equilibrium after forty minutes. The rapid absorption in the initial stages is a result of the availability of many vacant adsorption sites for benzene of the bulk solution. As time goes by, the number of vacant sites decrease hence benzene molecules compete for these available sites. It explains why the curve’s slope reduces. Consequently, one can deduce that benzene adsorption on rice husks depends on the film diffusion process. The process is activated by the high concentration difference between the bulk solution (benzene solution) and the pores of the adsorbent (the rice husks).
Why is this study significant to biology and to humanity? Toxic Benzene is absorbed mainly through the skin and by inhalation. When benzene is applied to the surface, a large portion is absorbed while the rest rapidly volatilizes. When inhaled, about 47% of the inhaled vapors are not excreted by the lungs. Biologically, such statistics are useful for the formulation of preventive and curative measures. One can understand the effects of this toxic organic pollutant. Additionally, this study enables human beings to understand the importance of water treatment. After realizing the dangers of exposure to this pollutant, one becomes more cautious about the things they consume.
Any scientific experiment is a milestone to humanity. Scientists devote their time to perform tests whose results should be taken into account. Recommendations that come with these results should be accorded the seriousness that they deserve. Some of them could be life-changing. As is the case of the removal of benzene from rice water, such an experiment is enlightening to people who insist on using water that has not been treated.