Cikapundung River is the main raw water source for 2-millions inhabitants of Bandung city but has been severely deteriorated due to organic pollution such as cattle manure, domestic, and agriculture wastes. Dissolved Organic Matter (DOM) in raw water can influence the process of water treatment. This study characterized and identified the origins of fluorescent DOM (FDOM) in Cikapundung River. Raw water samples were collected from intake outlets during dry and rainy seasons and analyzed using Fluorescence Excitation Emission Matrix spectroscopy combined with parallel factor (PARAFAC). FDOM origins were identified by Fluorescence-Index (FI) while autochthonous process contribution in water body was determined by Biological-Index (BIX). Chromophoric DOM as UV absorbance at 254 nm (A254) and Chemical Oxygen Demand (COD) were also measured. The FI were 1.82 (dry season) and 1.77 (rainy season), and the BIX were 0.92 (dry season) and 0.65 (rainy season). PARAFAC identified three compounds: water contaminant-like (C1), humic-like (C2) and tryptophan-like (C3) compounds. C2 was predominantly present in the rainy season with a C3/C2 ratio of 0.33. In the dry season, C3 increased substantially with a C3/C2 of 1.60. Strong correlation between C1 and C3 (R=0.86) was evidence that contaminant-like and tryptophan-like compounds were from the same anthropogenic sources. Strong correlation with A254 may indicate these identified compounds are aromatics.

Abstract. Fly ash is a particulate material produced from coal combustion power plants with major components are silica, alumina, iron oxide, calcium oxide, magnesium oxide, and carbon which are ideal for metal adsorbents. The potential use of fly ash in the wastewater treatment process is obvious because it can be obtained cheaply in large quatities and it can be used as an adsorbent. However, fly ash still shows lower adsorption capacity unless it is activated. In this study, fly ash activated by NaOH 14 M and KOH 14 M solutions. The batch experiments were carried out to study the sorption of copper ions from aqueous on alkali activated fly ash. The influence of initial concentration and contact time were examined at constant pH and dose of adsorbent. The sorption capacity of copper ions increased with the initial concentration and contact time. The sorption capacities followed the order Na1>Ka1>FA. The adsorption isotherm model exhibited that the Langmuir model is very suitable with copper ions adsorption onto fly ash and alkali activated fly ash. Kinetic study shows that adsorption of copper ions onto FA, Na1, and Ka1 follows the pseudo second-order kinetics.

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Abstract. The ability of fly ash to adsorp Cu(II) ions from two different coal combustion systems was studied. Optimum removal was found at pH 5, contact time 30 minutes and 60 minutes for Fly Ash 1 and Fly Ash 2, respectively, and dosage 10 g/l. The difference in adsorption capacity between both fly ashes may be due to their carbon fraction and CaO content. The removal of Cu (II) ions was caused by both adsorption and/or precipitation. Precipitation is enhanced by lowering the carbon fraction and increasing the CaO content. The adsorption isotherm showed that the Langmuir model fitted well to the experimental data of both fly ashes. A thermodynamic study was conducted at three different temperatures: 25 °C, 45 °C, and 60 °C. The adsorption processes were spontaneous and endothermic and were more favorable at higher temperature.

The continues deficiency of consumable water is a significant issue in developing countries, and contaminated water can result in various diseases, which are often lethal. Solar desalination seems to be a promising method and alternative way for supplying fresh water. <strong>Aim:</strong> The aim of this research is to study heat transfer in desalination system and the quality of feed water, distilled water and brine compared to the quality standard. Feed water consists of salinity 12‰ and 38‰ salinity. <strong>Methodology and Result:</strong> At first, initial characterization of feed water was conducted, then temperature on fourteen points was measured using thermocouples and thermometer so heat transfer rate can be calculated. After that, the final characterization of water production was conducted. From the  observation, it was found that evaporative heat transfer for vacuum pressure of -0.05, -0.1, -0.15, -0.2, -0.25, and -0.3 bar respectively were 173.77, 180.07, 190.79, 481.66, 242.57, and 246.24 W/m2. The result of water quality test of distilled water produced from saline water desalination for some parameters respectively were pH 7.4; turbidity 2.73 NTU; TDS 27.45 mg/L; chloride 84.98 mg/L; Fe 2.13 mg/L; total hardness 0.1698 mg/L; and <em>Escherichia coli</em> 12 cell/mL . <strong>Conclusion, significance and impact study:</strong> It can be concluded that distilled water produced by desalination system was met drinking water quality standard according to Minister of Health Regulation No. 492 of 2010.

The textile wastewater contains components of dye and inorganic salts which are very dangerous when they are directly discharged into the water body without any prior treatment. In this study, the ability of immobilized ceramic/ZnO nanoparticles (NPs) for decolorization of Reactive black 5 dyes was investigated. A laboratory scale of rotating disc type reactor with UV-C lamp and dip coating method to immobilize nanoparticles were used in this study. Ceramic/ZnO NPs were then characterized by SEM-EDS. EDS result has shown that 82% of ZnO NPs were dispersed on the ceramic surface with maximum catalyst dosage of 5.5 mg/cm2. It was achieved after 3 cycles of impregnation process at 500°C. Photocatalytic activity of ceramic/ZnO NPs was strongly depended on pH and RB5 initial concentration. It possesses the highest photocatalytic activity (100% of decolorization efficiency) at the extreme alkaline condition and low RB5 concentration (3 mg/L) after 90 min of treatment time.

Abstrak: Telah dilakukan penelitian tentang degradasi intensitas zat warna air gambut dengan fotokatalis ZnO. Penelitian ini meliputi proses pre-treatment dengan koagulasi dan post treatment dengan penentuan jumlah optimum fotokatalis ZnO, pH optimum dan konstanta laju reaksi (k). Hasil penelitian menunjukkan bahwa proses pre-treatment menggunakan koagulasi dengan koagulan aluminium sulfat pada dosis 110 ppm dan pH 6,5 dengan persentase penyisihan kekeruhan, warna dan TSS, masing-masing 89%, 78% dan 98%. Pada proses fotokatalis menunjukkan bahwa kondisi optimum proses degradasi intensitas zat warna pada air gambut memerlukan 0,5 g/L katalis ZnO, pH 4 dan wakti radiasi sinar UV selama 120 menit. Konstanta laju fotodegrdasi intensitas zat warna sebesar 0,0209 menit-1 dengan persentase degradasi sebesar 20,54 %. Air gambut sebelum perlakuan memiliki konsentrasi intensitas zat warna sebesar 527 Pt.Co dapat disisihkan menjadi 10 Pt.Co dengan kombinasi koagulasi dan fotokatalis ZnO. Abstract : Has done research on the degradation of color substances in peat water with photocatalystsZnO. This study includes pretreatment process with coagulation and post treatment to determine the optimum dose of ZnO photocatalyst, optimum pH and the reaction rate constant (k). The result showed that the pretreatment process using coagulation with Al2SO4 at 110 ppm dose, and pH 6,5 with the percentage of removal for turbidity, color and TSS are 89%, 78%, and 98%, respectively. Photocatalysts process showed that the optimum condition of color substance degradation in peat water requires 0,5 g/L ZnO, pH 4 and UV radiation for 120 minutes. Photodegradation rate constant of 0,0209 min-1 and the percentage of degradation is 20,54%. The peat water before treatment has color substance concentration can be set aside for 527 Pt.Co to 10 Pt.Co with the combination of coagulation and ZnO photocatalyts process.

Surface water pollution caused by industrial, agricultural, and domestic waste limit the availability of clean water sources. One solution is to use sea water as a source of clean water. Seawater desalination using solar energy is now growing. The purpose of this research is to study the effectiveness of desalination equipment with variation of vacuum pressure, number of trays, and type of feed water. First, the environmental conditions were measured, i.e. the intensity of solar radiation, ambient air temperature, and relative humidity. Then the distillator efficiency by variation of vacuum pressure, number of trays, and type of feed water was measured. From the result of observation, it was found that with radiation intensity ranged from 3967.86 - 6459.99 W/m2.day, ambient air temperature 22 - 28°C, and relative humidity 55 - 80%, distilled water produced was 7595 - 11,146 ml/day. The distillator efficiency for pressure of -0.05; -0.1; -0.15, -0.2; -0.25; -0.3 bar respectively were 25.54; 29.45; 29.56; 30.18; 30.90; and 37.77%. Distillator efficiency for evaporator from without tray until five trays were 24.89; 29.01; 27.88; 30.03; 34.05; and 37.77%. It was found that optimum distillator efficiency achieved at vacuum pressure of -0.3 bar and five trays in evaporator. Distillator efficiency for sea water (efficiency of 21.79%) was lower than brackish water (efficiency of 37.77%).