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The performance of membrane filtrations are mostly determined by pore structure of the fabricated membrane. Selection of polymer and solvent in membrane preparation are influence the morphology of fabricated membrane. The present work discusses the morphology of PES membrane fabricated from different polymer system with constant preparation condition. Polymer system consists of 15 wt% of polyethersulfone (PES) and 85 wt% of solvents. The homogeneous solution includes of PES-dimethyl sulfoxide (DMSO), PES-dimethylformamide (DMF), and PES-N-methylpyrrolidone (NMP). The purpose of this research is to investigate the effect of the types of solvent on the formed membrane morphology. Phase inversion technique is used to solidify the flat sheet membrane in deionized water as a coagulation bath. The scanning electron microscopy (SEM) was used to observe the morphology of membrane. A dead-end ultrafiltration module was carried out to observe the filtration performance of the fabricated membrane. It is proved that the different membrane solution affect the membrane structure in term of skin layer, macrovoid, and support layer. Furthermore, the changing of the membrane structure affected the pure water permeability (PWP). It is found that the highest PWP was reached up to 4.52 L/m2.hr.atm using PES-DMSO system.

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Mercury from the traditional gold mining activities in Aceh Jaya Regency causes water source and thus residents are exposed to mercury metals. In organic and inorganic conditions, mercury is toxic to the human body, causes damage to the nerve system, kidney failure, heart failure, blood pressure disorders, and damage to the immune system. The problem of mercury contamination can be chemically solved in various ways. This research uses polyurethane foam to adsorb mercury from water. The adsorption and selectivity of polyurethane foam adsorption can be improved through modification with Chitosan. In this research, preheating temperature, glycerol and toluene di-isocyanate (TDI) compositions greatly affect the physical form of foam. The condition under which optimal glycerol composition used for synthesizing the polyurethane foams is 20% (w/w of mixture A). This glycerol composition results in polyurethane foams with an optimum ratio of the mixture A/TDI/distilled water of 2 : 1 : 1. The best adsorption is obtained with polyurethane foam added by 2.5% Chitosan. The optimum mercury adsorption 25% is resulted from the operating time of 60 minutes with adsorption capacity of 0.313 mg/g. For Chitosan modified polyurethane foam, research points out that the reaction is the second order reaction. The result concluded that the polymer has semi crystalline crystallization and melting temperatures.

Hospital wastewater basically contains organic materials and inorganic materials. Levels of these materials can be determined by testing of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Dissolved Solid (TDS), and Total Suspended Solid (TSS). The hospital wastewater treatment proposed in this research is the electrocoagulation treatment using electrodes Fe-Fe and uses the response surface method for optimizing the response variable. Referring to this resea rch, the result shows that the relationship between the process variables and the TSS is significantly influential. As the contact time (15, 30, and 45 minutes) is longer and the voltage (6, 9, and 12 volts) is higher, the percentage reductions of TSS increase. However, the electrolyte solution (0–1 M) has little influence/significance to a response variable of TSS. The highest percentage of TSS reduction is at the contact time 30 minutes and 12 volts, which declined at contact time 45 minutes. The model recommended is a quadratic form with a low error less than 1.6%. In such a way, the optimum condition is at contact time 36 minutes, voltage 12 volts, and the electrolyte (NaCl) concentration 0.1 M. The reduction percentage is TSS 72.45%.