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The vast utilizing of aniline in diverse industrial applications makes it predominantly recognized in the eco-geological system. This work investigated the feasibility of reverse osmosis (RO) and nanofiltration (NF) membranes for the removing of aniline from wastewater. The performance of the TFC spiral wound membrane was examined with different operating parameters. The effect of feed concentration (10-200 mg/l) and operating pressure (1-4 bar) on flux and aniline rejection were explored. Additionally, the fouling test for the adopted membranes was conducted for 20 h using NaOH as cleaning agent. The results revealed that a high rejection ratio at noticeable low operation pressure was achieved by using TFC membranes for both of the RO and NF technologies. The maximum aniline rejection was 99.8% and 93.25% under a 1 bar pressure and the concentration of feed 10 mg/l for the RO and NF membranes, respectively. These rejection ratios correspond to the permissible concentration of aniline in the wastewater. The water flux obtained was 6.33 and 13.5 LMH for reverse osmosis and nanofiltration membranes, respectively. The augmentation of operation pressure resulted in decreasing of rejection and rising of the flux. The fouling test showed a reduction in flux of about 0.92 and 4.35% for RO and NF membranes, respectively, from its initial value before membrane cleaning. The results also demonstrated that the reverse osmosis membrane is better than the nanofiltration membrane in terms of removal efficiency.

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The moisture sorption isotherms of Mefenamic acid tablets were investigated by measuring the experimental equilibrium moisture content (EMC) using the static method of saturated salt solutions at three temperatures (25, 35, and 45°C) and water activity range from 0.056 to 0.8434. The results showed that EMC increased when relative humidity increased and the sorption capacity decreased, the tablets became less hygroscopic and more stable when the temperature increased at constant water activity. The sorption curves had a sigmoid shape, type II according to Brunauer’s classification. The hysteresis effect was significant along with the whole sorption process. The results were fitted to three models: Oswin, Smith, and Guggenhein - Anderson and de Boer. According to the fitting results, the GAB model was the most appropriate model to describe the sorption behavior of Mefenamic acid; it had a regression coefficient range (0.9803-0.994), %E (0.69-4.06), and low values of SEE (0.85-2.2). The monolayer moisture content was calculated using the GAB model and it was concluded that the tablets should be stored at moisture content equal or slightly higher than (0.2046, 0.1843, and 0.1437 %) for desorption and (0.2073, 0.1269, and 0.1452 %) for adsorption for the three temperatures.