چكيده به لاتين
Two environmental problems that threaten the international community are oil spills and waste rubbers which have caused both health and environmental problems. In this work, we provide a new way to dispose NBR waste rubbers by reusing the waste rubber for separation of oil from seawater. To investigate this feasibility, firstly, Silica nanoparticles were modified with vinyl silane. To achieve the optimal concentration, silane with three different concentrations (X, 5X and 10X) was added to the silica nanoparticles according to the formulation. Optimized modified nanoparticles were selected according to the analysis of FTIR, TGA, XRD and BET. XPS analysis was performed to confirm the surface modification which confirmed the emergence of peak C1s in interval 284eV which was related to grafted silane. Then, recycled/devulcanized NBR composites were selected and prepared due to their resistance to petroleum solvents. To select the optimal content of pristine nanosilica, rubbery composites were prepared at different nanopartcle concentrations (1%, 2%, 3%, 5% and 10%). To select the optimal samples, MDR and tensile tests were performed. Then, modified nanosilica was added to the selected compound samples. The mechanical and curing behavior of recycled NBR were compared to new NBR samples. Modified nanocomposites showed very good performaces in terms of chemical and mechanical properties which were confirmed by payne effect, wet skid resistance and heat build up test too. Finally, the modified composites were tested for absorption of Persian Gulf oil. The modified recycled samples lasted up to 700 cycles and the modified pristine samples lasted up to 1000 cycles of oil absorption/desorption cycles. However, the recycled samples had higher absorption (1.5 g/g) than pure samples (1.3 g/g). Persian gulf oil separation efficiency was above 99% for all modified samples. The oil contact angle (OCA) for the optimal sample of modified recycled nanocomposite was 11.1° and the water contact angle (WCA) was 153.3°. Due to their cost-effectiveness, high efficiency and the availability of waste rubbers in the community, these waste rubbers can be used for a bigger problem, namely oil/water separation and separation of oil from seawater.
