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The present study deals with the removal of phosphorus from wastewater by using oven-dried alum sludge (ODS) as adsorbent that was collected from Al-Qadisiya treatment plant (Iraq); it was heated in an oven at 105• C for 24 h and then cooled at room temperature. The sludge particles were then crushed to produce a particle size of 0.5-4.75 mm. Two modes of operation are used, batch mode and fixed bed mode, in batch experiment the effect of oven-dried alum sludge doses 10-50 g/L, pH of solution 5-8 with constant initial phosphorus concentration of 5 mg/L, and constant particle size of 0.5 mm were studied. The results showed that the percent removal of phosphorus increases with the increase of oven-dried alum sludge dose, but pH of solution has insignificant effect. Batch kinetics experiments showed that equilibrium time was about 6 days. Adsorption capacity was plotted against equilibrium concentration, and isotherm models (Freundlich, Langmuir, and Freundlich-Langmuir) were used to correlate these results. In the fixed bed isothermal adsorption column, the effect of initial phosphorus concentration (C o ) 5 and 10 mg/L, particle size 2.36 and 4.75 mm, influent flow rate (Q) 6 and 10 L/hr, and bed depth (H) 0.15-0.415 m were studied. The results showed that the oven-dried alum sludge was effective in adsorbing phosphorus, and percent removal of phosphorus reaches 85% with increasing of contact time and adsorbent surface area (i.e., mass of adsorbent 50 g/L with different pH).

This work aims to study extraction of essential oil (EO) from peppermint leaves using hydro-distillation methods. The peppermint oil extraction with hydro-distillation method studied the effect of the extraction temperature on the yield of peppermint oil. Besides, it also studied the kinetics during the extraction process. The second-order mechanism was adopted in the model of hydro-distillation to estimate many parameters such as the initial extraction rate, capacity of extraction, the constant rat of extraction at various temperatures and activation energy. The results showed that the extraction process is a spontaneous process, since the Gibbs free energy has a negative value at all studied temperatures. For example the Gibbs free energy at (70, 80, 90, and 100 ºC)were (-2.93, -3.84, -4.75, -5.66) respectively.

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