Development of anti-foulant ultraviolet-assisted polyvinyl alcohol layer on the polysulfone-based nanohybrid membrane for industrial rubber wastewater decontamination

Introduction: Membrane fouling has been reported to be one of the bottlenecks of membrane technologies for wastewater treatment. To mitigate its negative impacts, we fabricated polysulfone membrane (PSf) composites made of silica (SiO2) and graphene oxide (GO) nanoparticles that modified with ultraviolet (UV)-assisted polyvinyl alcohol layer on the membrane surface.Methods: The membrane composite was synthesized using non-solvent induced phase separation (NIPS) method. The membrane was further treated by UV irradiation and cross-linked with PVA coating to cope with the fouling problem. The modified membrane was applied for industrial rubber wastewater decontamination.Results: The UV irradiation and cross-linked PVA coating to the PSf/GO-SiO2 membrane improved the pseudo-steady state permeate flux by 60.15% from 20.05 to 50.32 L/m2hr and maintained the permeate flux up to 82.33%. About 85% of total dissolved solids (TDS), 81% of chemical oxygen demand (COD), and 84% of ammonia compound (NH3) with initial concentrations of 335.76, 242.55, 175.19 mg/L, respectively, could be removed after 8 h of membrane treatment. The modified membrane also exhibited an excellent flux recovery ratio of up to 83%.Discussion: The modified membrane changed the fouling mechanism from pore blockage to cake filtration, which signifies the capability of the membrane to tackle severe fouling tendency. The cross-linked UV/PVA coating reduced fouling formation by reducing the adsorptive interactions between the foulant molecules and the membrane surface by enhancing membrane surface hydrophilicity. This implies that incorporating GO/SiO2 nanoparticles with UV irradiation and PVA coating substantially enhanced the physicochemical properties of the PSf membrane

Statistical approaching for superhydrophobic coating preparation using silica derived from geothermal solid waste

Material quality can be affected by humidity resulting in short durability. Many observations have been conducted to endure the durability of material, such as coating methods. However, currently available methods are unaffordable. Therefore, this paper observes efficient and effective method to prepare superhydrophobic silica coatings derived from geothermal waste. The method was conducted by spraying. The objective of this paper is to observe optimum condition by using variables of silica concentration, TMCS (trimethylsilyl chloride) concentration, solvents and materials confirmed by contact angle of material based on statistical analysis. The study consisted of silica treatment for purification and preparation of superhydrophobic silica coatings. The study was carried out with factorial design of 81 experiments with one-time replication through Design Expert software (version 8.0.6). Based on previous research, the experiment was obtained optimum condition at 5.5%w/v, 13%v/v, isooctane, zinc coated for silica concentration, TMCS concentration, solvent and material, respectively, releasing contact angle by instrumentation of 180°. By ANOVA analysis, it was also complied the optimum condition of the superhydrophobic coating solution preparation achieved the same condition with experimental data releasing contact angle of 179.69°

Design simulation and economic optimization of a benzene-toluene-xylene system distillation process upon the energy cost

Distillation is the most extensively used in separation process of the chemical industry. Relationships between non-linear variables, multivariable interactions, dynamic system properties, and other irregularities render the study of design simulation and process optimization an interesting challenge for process engineers. The objective of the process optimization is to produce the most economical to conduct the system. This paper discusses the process engineering strategy started from the determination method of the degree of freedom, design variables, process tools, economic parameters, and the optimization process. The distillation variable optimized in this study was limited to reflux ratio. The optimum variable was construed from the reflux ratio producing the lowest total annual cost (TAC). Furthermore, it was analyzed the energy cost as optimization parameter in the total annual cost (TAC) calculation method to obtain minimum reflux ratio in distillation unit

Development of anti-foulant ultraviolet-assisted polyvinyl alcohol layer on the polysulfone-based nanohybrid membrane for industrial rubber wastewater decontamination

Membrane fouling has been reported to be one of the bottlenecks of membrane technologies for wastewater treatment. To mitigate its negative impacts, we fabricated polysulfone membrane (PSf) composites made of silica (SiO2) and graphene oxide (GO) nanoparticles that modified with ultraviolet (UV)-assisted polyvinyl alcohol layer on the membrane surface