Danu Ariono

Integrated processes for desalination and salt production: A mini-review

The scarcity of fresh water due to the rapid growth of population and industrial activities has increased attention on desalination process as an alternative freshwater supply. In desalination process, a large volume of saline water is treated to produce freshwater while a concentrated brine is discharged back into the environment. The concentrated brine contains a high concentration of salt and also chemicals used during desalination operations. Due to environmental impacts arising from improper treatment of the brine and more rigorous regulations of the pollution control, many efforts have been devoted to minimize, treat, or reuse the rejected brine. One of the most promising alternatives for brine handling is reusing the brine which can reduce pollution, minimize waste volume, and recover valuable salt. Integration of desalination and salt production can be implemented to reuse the brine by recovering water and the valuable salts. The integrated processes can achieve zero liquid discharge, increase wat...

Preparation and characterization of polysulfone/PEG heterogeneous ion exchange membrane for reverse electrodialysis (RED)

Heterogeneous cation-exchange membrane is synthesized using solution casting method. The casting solution is prepared by dispersing finely ground cation-exchange resin particles in N,N-dimethylacetamide (DMAc) solutions of polysulfone (PSf) while polyethylene glycol (PEG400) is used as a modifier. The results show that the PEG400 can increase water uptake, conductivity, and ion-exchange capacity (IEC) of the heterogeneous cation-exchange membrane due to the hydrophilic nature of PEG400. The more hydrophilic membrane results in higher water uptake and wider access for functional sites. However, when the concentration of PEG400 is increased further, the IEC and conductivity tend to decrease. This tendency is more pronounced when the ion-exchange resin particle is increased from 50 to 60%-wt. It could be attributed to the washed out of some ion-exchange particle during membrane immersion due to lower bonding between membrane matrix and the particles.

Determination of thermodynamic properties of polysulfone/PEG membrane solutions based on Flory-Huggins model

Flory-Huggins (F-H) model was used to study thermodynamic properties of polysulfone-based membrane solution that consists of water, dimethylacetamide (DMAC), polysulfone (PSf), and polyethylene glycol (PEG400). The thermodynamic properties of membrane solution were examined based on equilibrium composition in a ternary diagram of the membrane system, which known as binodal curve. The binary interaction parameters of each component in F-H model were predicted based on cloud point experiment at various PSf and PEG400 concentrations and used to calculate the binodal curve in ternary diagram. It was obtained that the binary interaction parameters in the membrane solution are: X13 (water–PSf) = 6.76, g14 (water–PEG400) = 0.51, g23 (DMAc–PSf) = 0.46, g24 (DMAc–PEG400) = 0.46, and g34 (PSf–PEG400) = −0.53. Based on the thermodynamic analysis in the ternary diagram, low solubility of membrane solution was achieved when 20 wt% of PSf was blended with a high concentration of PEG400 (20–30%). It means that the membr...

EKSTRAKSI MINYAK DAN RESIN NYAMPLUNG DENGAN CAMPURAN PELARUT HEKSAN-ETANOL

Calophyllum seeds are potential to be used as raw material for vegetable oil production due to their high oil content ( 75.1 % db ). In addition, C alophyllum seeds contain resin consisting beneficial phenolic compound s for health. In this study, C alophyllum seeds were extracted using hexane-ethanol mixture to investigate oil and resin yields and their physicochemical properties , and to obtain the best process condition in oil and resin production from C alophyllum seeds. Experiment was carried out using r andomized c omplete d esign with three factors, i.e. extraction time s (5-7 h ), temperature s (40-50°C) , and hexane to ethanol ratio s ( 2 : 4 , 3:3 and 4 : 2 ). The result of variance analysis showed that extraction time and hexane to ethanol ratio affected significantly on oil and resin yield s , density, acid and iod value s, whereas temperature influenced only on oil yield , density and acid value . Best oil (58.2%) and resin (16.2%) yields were respectively obtained at 5h extraction time, 50°C temperature and 4:2 hexane to ethanol ratio, and 5hextraction time, 4 0°C temperature and 2:4 hexane to ethanol ratio. At these optimum conditions, the oil had acid value of 1 4 . 89 mg KOH/g, iodine value of 60.75 g iodine/100 g , viscosity (25 °C ) of 71 . 46 mPa.s, and density (25 °C ) of 0.8 6 g/ cm 3 . On the other hand, t he resin had acid value of 1 33 . 76 mg KOH/g. Keywords: C alophyllum, extraction, ethanol , hexane, oil, resin

Review of hydrophilic PP membrane for organic waste removal

The acceleration of industrialization in developing countries has given an impact of environmental pollution rapidly, such as contamination of groundwater with organic waste. To solve this problem, some membrane techniques have been performed to remove organic waste from water, such as membrane contactors, membrane bioreactors, and supported liquid membranes. Polypropylene (PP) membrane is one of the promising candidates for these membrane processes due to its chemical stability, low cost, good mechanical resistance, and being easily available. However, different processes require membranes with different surface properties. Hydrophobic PP membranes with excellent chemical stability can be directly used in membrane contactors, in which the organic phase wets the porous membrane and slightly excessive pressure applied to the other phase. On the other hand, hydrophilization of PP membrane is necessary for some other processes, such as for fouling reduction on membrane bioreactors due to organic matters depo...

The effect of polymer concentration on flux stability of polysulfone membrane

The influence of various polymer concentrations on flux stability of polysulfone membranes was investigated. The polysulfone membrane was prepared by blending polysulfone in DMAc with 25%wt concentration of PEG400 and 4% wt concentration of acetone. It was found that the pure water flux was sharply decreased from 1230 to 7 Lm-2h-1, when the polysulfone concentration was increased from 14% to 24%wt. Furthermore, the increase of polysulfone concentration also affects the fouling behavior of the membranes, in which almost of 90% of FRR was achieved by the addition of 18 %wt of polysulfone concentration. It was suggested that fouling formed on the membrane surface was dominated by reversible fouling, thus it could be easily cleaned by flushing method. In addition, the applied transmembrane pressure (TMP) also plays an important role in fouling behavior of polysulfone membrane. It was observed that irreversible fouling of organic matter was deteriorated by the increase of TMP, which contributed to the reduction of water flux. More stable membrane flux performance was achieved although it was operated at high TMP, when 20% wt concentration of polysulfone was added into membrane solution.The influence of various polymer concentrations on flux stability of polysulfone membranes was investigated. The polysulfone membrane was prepared by blending polysulfone in DMAc with 25%wt concentration of PEG400 and 4% wt concentration of acetone. It was found that the pure water flux was sharply decreased from 1230 to 7 Lm-2h-1, when the polysulfone concentration was increased from 14% to 24%wt. Furthermore, the increase of polysulfone concentration also affects the fouling behavior of the membranes, in which almost of 90% of FRR was achieved by the addition of 18 %wt of polysulfone concentration. It was suggested that fouling formed on the membrane surface was dominated by reversible fouling, thus it could be easily cleaned by flushing method. In addition, the applied transmembrane pressure (TMP) also plays an important role in fouling behavior of polysulfone membrane. It was observed that irreversible fouling of organic matter was deteriorated by the increase of TMP, which contributed to the reductio...

Improving ion-exchange membrane properties by the role of nanoparticles

Extensive application of synthetic ion-exchange membrane (IEM) in many areas has necessitated the improvement of their properties. Recently, the introduction of nanoparticles into polymeric membrane has attracted growing interest since the combination of both materials results in better properties. This well-known mixed-matrix membrane exhibits superior characteristics compared to an individual polymeric membrane. Properties of the nanoparticles such as electrical conductivity, hydrophilicity, and adsorption capacity can be utilized to produce the IEM with better physicochemical, electrochemical, and mechanical characteristics. The nanoparticles may also be used to achieve a specific characteristic such as an antibacterial property and monovalent ion permselectivity. In this paper, preparation, the role of inorganic materials and performance of mixed-matrix IEM are reviewed. In addition, challenges facing mixed-matrix IEM and strategies taken to overcome those challenges and future perspectives are discussed.Extensive application of synthetic ion-exchange membrane (IEM) in many areas has necessitated the improvement of their properties. Recently, the introduction of nanoparticles into polymeric membrane has attracted growing interest since the combination of both materials results in better properties. This well-known mixed-matrix membrane exhibits superior characteristics compared to an individual polymeric membrane. Properties of the nanoparticles such as electrical conductivity, hydrophilicity, and adsorption capacity can be utilized to produce the IEM with better physicochemical, electrochemical, and mechanical characteristics. The nanoparticles may also be used to achieve a specific characteristic such as an antibacterial property and monovalent ion permselectivity. In this paper, preparation, the role of inorganic materials and performance of mixed-matrix IEM are reviewed. In addition, challenges facing mixed-matrix IEM and strategies taken to overcome those challenges and future perspectives are discussed.

Transesterifikasi In Situ Biji Jarak: Pengaruh Kadar Air dan Ukuran Partikel Bahan terhadap Rendemen dan Kualitas Biodiesel

The objective of this study was to investigate in situ transesterification process allowing to realize directly biodiesel production from jatropha seeds. The influence of moisture content (0.5, 2, 3 and 4 %) and particle size (10, 20 and 35 mesh) of jatropha seeds was examined to determine the best performance of the biodiesel production yield and its quality. Generally, the moisture content and particle size of jatropha seeds affected biodiesel production yield. An increase of biodiesel production yield was observed as moisture content and particle size of jatropha seeds were decreased. Highest biodiesel production yield (71 %) was obtained under seed moisture content of 0.5 % and particle size of 35 mesh. Effect of the moisture content and particle size of jatropha seeds on biodiesel quality was less important. In all experiments tested, the biodiesel quality was very good. The acid value was below 0.3 mg KOH/g of biodiesel, water and sediment content was very poor ( 210 mg KOH/g of biodiesel). In addition, quality of biodiesel produced under optimum process condition was in accord with Indonesian Biodiesel Standard. Keyword: Transesterification, in situ, jatropha seed, biodiesel ABSTRAK Kegiatan penelitian ini bertujuan untuk mempelajari proses produksi biodiesel secara langsung dari biji jarak melalui proses transesterifikasi in situ. Parameter kondisi proses yang dipelajari adalah pengaruh kadar air (0,5, 2, 3 dan 4 %) dan ukuran partikel bahan (10, 20 dan 35 mesh) terhadap rendemen biodiesel dan kualitasnya. Kadar air dan ukuran partikel bahan berpengaruh nyata terhadap rendemen biodiesel. Semakin kecil kadar air dan ukuran partikel bahan, rendemen biodiesel dan efektifitas proses transesterifikasi in situ biji jarak semakin meningkat. Rendemen biodiesel tertinggi (71 %) dihasilkan dari perlakuan kadar air dan ukuran partikel bahan 0,5 % dan 35 mesh. Biodiesel yang dihasilkan dari proses transesterifikasi in situ biji jarak mempunyai bilangan asam, viskositas, air dan sedimen yang relatif rendah, yaitu 0,27 mg KOH/g biodiesel, 210 mg KOH/g biodiesel. Ukuran partikel bahan tidak berpengaruh nyata terhadap bilangan penyabunan dan ester biodiesel, sedangkan kadar air bahan menunjukkan pengaruh yang nyata. Kata kunci: Transesterifikasi, in situ, biji jarak, biodiesel