Desalination of brackish water using ion exchangers prepared from Omani date palm leaflets

Oman belongs to arid countries with limited annual precipitation and 90 % of the available fresh water comes from ground water. About 92 % of the available fresh water is used for agriculture. The Omani population, in the last 3 decades, has increased with a great expansion in industry leading to an increase in water demand and, thus, more consumption of ground water. Over-pumping of ground water has led to sea water intrusion and ground water salinization. The increased salinity of ground water along the coastal wilayat in South and North Al-Batinah governorates, the highest agricultural region in Oman, has led to dramatic consequences on crops and soil in that region. The proposed project intends to introduce cationic and anionic exchangers from date palm leaflets. First, dehydrated carbon is prepared via the dehydrative and oxidative effect of sulfuric acid. Activated carbon is prepared via ZnCl2 activation followed by surface oxidation. The surface of the carbon will be functionalized using diamine and triamines short chain derivatives followed by conversion to tertiary amine functional groups that act as strong anionic exchanger. Another surface functionalization of the dehydrated carbon and oxidized activated carbon will be carried out using amine sulfonic derivatives to produce loaded carbon with sulfonic acid groups that act as strong cationic exchangers. Both types of ion exchangers will be mixed and tested for desalting the brackish water in Al-Batina farm wells along the coastal wilayat. The project will constitute bench studies for the removal of cations of Na+, Ca2+ and Mg2+ as most abundant metals in brackish water in addition to some anions such as SO42-, NO3-, Cl-. Brackish water will be tested for treatment using a filter from the ion exchangers selected for best performance. A group of analytical techniques such as ICP-MS, AA and ion chromatography will be utilized to evaluate the level of cations and anions in brackish water before and after the treatment. Batch and filter column studies will be carried out for desalting brackish water. In addition, soil across the coastal plane in Al-Batinah region will be sampled and analyzed.