bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of change of land-use type on hydrological cycle
Authors: Xiaoyong Wang , Lihe Yin , Honglin MA , Zebing Dai , Jiaqiu Dong , Xueqin Zhang
Published: February 2021

Change of land-use pattern causes the change of underlying surface environment in the basin, thus influencing the source and sink of hydrological cycle in the study area and to greatly affect the groundwater level. In order to study the relationship between underlying surface change and groundwater level, this paper quantitatively analyzed the remote sensing images of the Hailiutu River basin acquired in different periods and collected long-series groundwater monitoring data, and this paper drew a groundwater level change map by calculating the transfer matrix of different land-use types. On this basis, this paper analyzed the groundwater level and influential factors for the transfer amount of different land-use types. Results showed that the change in groundwater level was mainly influenced by the underlying surface change. The land-use types exhibited strong tempo-spatial transformation. Where there was a drastic change of land-use type, there was a sharp change in groundwater level, indicating that the change of land-use type greatly influenced the underlying surface and was positively correlated with the spatial distribution of groundwater level.
Application of low-cost mesoporous geopolymer for dye waste removal
Authors: Fitriani Evi , Purbasari Aprilina
Published: February 2021

Abstrak

Environmental pollution causes a significant reduction in water quality. Sustainable development and industrial waste pollution are the supporting factors for the amount of water that is not suitable for consumption. Contaminants in wastewater that pollute water sources include phenolic compounds, substituted compounds, various types of pesticides, and dyes. This study focuses on developing geopolymers as a low-cost alternative adsorbent for adsorbing harmful dyes. Geopolymers can rapidly absorb dyes due to their supportive surface properties to absorb dyes. The porous structure is derived from alumino-silicate materials such as kaolin, metakaolin, dolomite, fly ash, and slag which have been activated with alkaline or alkaline silicate solution. Geopolymers are readily stored adsorbents. Geopolymers have shown good adsorption capacity of the dyes of Methylene blue, Rhodamine B, Congo Red, Methyl Orange, Methyl Violet. This study aims to provide an overview of the types of geopolymer forming materials, geopolymer characterization, application of geopolymers as dye adsorbents, and comparison with other adsorbents. The adsorption isotherm model and adsorption kinetics are also summarized in this overview.
Adsorptive removal of methylene blue from aqueous solution onto koh-activated carbons derived from saba banana (m. Acuminata balbisiana) peel
Authors: Parmita Ade Wahyu Y P , Hartanti Ansita F B , Ernawati Lusi , Laksono romeda Dwi , Iskandar Zulkarnain M , Fadila Febryela Alda
Published: February 2021

Organic pollutants in water are an increasingly prominent problem. Given this challenge, this study reported the high adorptive removal of methylene blue (MB) onto potassium hydroxide (KOH)-activated carbon. To prepare activated carbon, saba banana peel that are local organic waste were carbonized at 400 ° C and activated using various KOH concentrations, e.g.(0,5, 1 and 1,5 M). Physical and microstructural properties of activated carbon were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), and Fourier Transform Infrared (FTIR). The efffect of KOH concentrations on the adsorption perfromance of MB on KOH-activated carbon were further investigated. The adsorption process occurred more easily after KOH (1,5 M) of concentration and the adsorption capacity of activated carbon improved by more than 23 %. These results indicate that preparing Banana fruit peels-derived activated carbon using KOH activation is an effective way to reduce pollution and utilize a waste resource.
Adsorption of Pb(II) from aqueous solution by acid-modified water hyacinth cellulose
Authors: Tsaniatri D A , Hargono H
Published: February 2021

Water hyacinth has high cellulose content so that its potential to increase the adsorption capacity of heavy metal. Besides has containing cellulose, water hyacinth also contains lignin, which can inhibit the adsorption process. Delignification of water hyacinth was conducted by NaOH so that the cellulose content in water hyacinth increases as the lignin decreases. The research aimed to study the effect of nitric acid-modified on Pb(II) adsorption capacity. The various nitric acid at 0.2, 0.6, and 1 M concentrations. The influence of pH, contact time, and initial metal ion concentration in the adsorption process was studied. The analysis of Pb(II) metal ion contents in a solution used Atomic Absorption Spectrometer (AAS). Results showed that the best of Pb2+ adsorption is water hyacinth cellulose adsorbent with nitric acid modification of 1 M (D) was 8.6403 mg/g. The lowest adsorption was observed at 99.8883% for Pb2+ ion at pH 4, while the highest adsorption was 99.9477% at pH 7. The optimum contact time for Pb2+ adsorption at 100 minutes. The amount of Pb2+ ions adsorbed enhancement with an increase in the initial metal ion concentration.
Enhanced wash-fastness of cotton fabric dyed with a composite of chitosan-natural dyes extract of Ceriops tagal
Authors: Kartini I , Halimah S N , Rahayuningsih E
Published: February 2021

Chitosan coating on dyed cotton fabric by the natural dye of Tingi (Ceriops tagal) has been done to improve the wash fastness. Hydrophobic coating using HDTMS (hexadecyltrimethoxysilane) was also introduced to obtain multifunctional textiles. Fabric dyeing was done by the dip-coating method in two ways, one-pot (Op) and layer-by-layer (LbL). Specular-reflectance (SR) UV-Vis spectrophotometer was used to access the dyeing quality. An infrared spectrophotometer evaluation was performed to indicate the possible interaction between chitosan and the dye on the dyed cotton fabrics. The leaching degree was determined by using sodium dodecyl sulfate (SDS) and lerak (Sapindus rarak) natural surfactant as the leaching agents. The results showed that LbL coating has shown better dye-coverage on the cotton fabrics compared to the Op coating. However, cotton fabric coated by chitosan/tingi (Op) showed better performance than that of the LbL, with a leaching degree of 6.2% on SDS leaching, and 4.1% on lerak’s leaching. While, for LbL coating, the leaching degree was 20.1% on SDS and 13.9% on lerak’s leaching. The hydrophobic coating was stable and not affected by leaching. Different types of molecular interaction between the dye and chitosan from different coating techniques may result in those different performances on leaching.
Fabrication and application of ZnO-Ag nanocomposite materials prepared by gas-phase methods
Authors: Kusdianto K , Sari T D , Laksono M A , Madhania S , Winardi S
Published: February 2021

Zinc oxide nanoparticles have been used in various applications because of its unique physical and chemical properties. Unfortunately, the performance of pristine ZnO is inhibited by electron-hole recombination. The zinc oxide performance can be improved by metal doping to enhance its properties. This review paper provides summary of the synthesis and application of zinc oxide doped by silver (Ag) using different synthesis via gas-phase methods. From this review, synthesis parameters that will affect the ZnO-Ag nanoparticle and its application will be concluded. The gas-phase synthesis methods include flame spray pyrolysis, spray pyrolysis, sputtering, plasma enhanced chemical vapor deposition, electron beam evaporation, atomic layer deposition and electrospinning. It is clearly observed that the morphology, crystallinity, and performance of ZnO-Ag nanocomposite is significantly affected by the fabrication method. The precursors used, spray rate, deposition rate, precursor concentration, deposition time, morphology of the nanoparticle and deposition or annealing temperature affect the performance capability of ZnO-Ag. We believe that this review paper will provide valuable information and new insights into possible fabrication methods of ZnO-Ag nanocomposite materials in the gas-phase, which can be used for many applications as photocatalyst, anti-microbial applications, catalyst for hydrogen production as well as in dye-sensitized solar cells and gas sensors.
ZnO-TiO2 nanocomposite materials: fabrication and its applications
Authors: Kusdianto K , Nugraha D F , Sekarnusa A , Madhania S , Machmudah S , Winardi S
Published: February 2021

Zinc oxide (ZnO) is one of the most commonly used semiconductor materials for various applications, namely as photocatalysts, gas sensors, antimicrobial substances, and photovoltaic cells. The performance of the particles is greatly influenced by the morphology and the optical properties of the particles itself. To improve the performance of ZnO, one method which can be applied is by doping support with other semiconductor materials, such as TiO2. This is caused by electron transfers between ZnO and TiO2 which are able to enhance the stability of ZnO and the electron mobility of TiO2. Therefore, the electron-hole recombination can be inhibited by this mechanism. Fabrication of ZnO-TiO2 can be prepared by several methods, which is gas or liquid phases and solid phase. Spray pyrolysis, chemical vapor deposition, micro-arc oxidation, electrospinning and electron beam evaporation are preparation method for gas-phase synthesis, while sol-gel, hydrothermal, precipitation, solution combustion, pulse plating, and wet impregnation are for liquid phases. In this study, the fabrication methods of ZnO-TiO2 and its application have been reviewed as well as the factors that affect the morphology, performance, and the stability of ZnO-TiO2 nanocomposite. This review is conducted by comparing the analysis results with their performances. It is clearly found that there is an optimum condition for obtaining the best photocatalytic performance by adjusting the ratio of ZnO to TiO2. Furthermore, ratio of ZnO:TiO2 concentration on antimicrobial activity shows a linear performance, and it is obviously observed that the ZnO- TiO2 nanocomposite shows a better performance compared to the pristine ZnO or TiO2 in various applications. We believe that this review will provide valuable information and new insights into possible fabrication methods of ZnO-TiO2 nanocomposite materials, which can be used in many applications.
Fabrication of High Performance PSf-rGO/TiO2 UF Membrane for Ruberry Wastewater Treatment
Authors: Kusworo T.D. , Wulandari Lutfi Mia
Published: February 2021

Membrane technology is commonly used because it is one of the most effective and efficient technologies in producing clean water. The PSf-rGO / TiO2 UF (Ultra Filtration) membrane was synthesized using the phase inversion NIPS method. The membrane was synthesized by modifying the membrane surface by adding rGO / TiO2 nanoparticles to achieve the best performance. The membrane matrix used wasthe polymer of Polysulfone (PSf) with 0, 0.5, 1, and 1.5 wt% nanoparticles addition and UV irradiation time of 0.5, 1, 3, and 5 minutes. The higher concentration addition of rGO / TiO2 at 1.5% resulted in the best permeability. Meanwhile, the UV irradiation time of 3 and 5 minutes were the lowest time to gain permeability value.
The effect of legen treatment on fermentation process in production of nata de legen
Authors: Hendrianie N , Putri S N , Satria Y I
Published: February 2021

Palmyra palm (Borassus flabellifer) is one of the most widely cultivated plants in Indonesia, especially in Gresik, East Java. The number of Palmyra palm trees in that area is estimated to be approximately 5,000,000. The Palmyra palm tree produces a large amount of legen obtained by tapping the palm flower and its use now is only limited as a beverage. By processing the legen into the nata, it would increase its selling price and the local people’s income. In this research, the method used to produce the nata de legen was by fermenting the legen using the microbial Acetobacter xylinum. This method was the same as for producing the nata de coco from coconut water. There were various methods of pre-treatment of the legen before the fermentation process. The legen was stored at room temperature 30°C, cooled in a refrigerator for 2 hours, or heated at 100°C for 10 minutes, with incubation time was 10 days respectively. The results showed that the quality of the nata de legen was affected by the pre-treatment of the legen. The best quality of the nata obtained was its thickness of the 4 mm and the cellulose content of 23.25% under pre-treatment condition at 100°C
POLY LACTIC ACID (PLA) DEVELOPMENT USING LACTIC ACID PRODUCT FROM RICE STRAW FERMENTATION WITH AZEOTROPIC POLYCONDENSATION PROCESS
Authors: maryanty Yanty , Hadiantoro Sigit , Widjajanti Kristina , Putri Dahniar Ika Kusuma , Nikmah Lailatul
Published: February 2021

Polylactic acid ( PLA) is the raw material for the manufacture of environmentally friendly plastics since microorganisms more easily destroy it in nature. PLA had made from renewable materials such as wood, such as agricultural waste, such as lignocellulose-containing rice straw. Azeotropic polycondensation method has been using for the processing of PLA. This method is relatively simple and can yield a high molecular weight of PLA. Xylene solvent had used to absorb water, and the SnCl2 catalyst has used to accelerate the reaction. The polymerization process lasts 30 hours. The results of the polymerization process were deposited with excess methanol and then filtered with a vacuum pump and then toasted at 800C within 2 hours, resulting in PLA crystals in the form of yellowish-white powder. The best condition is that the 40-gram mass variation produces PLA with a yield of 49.6 per cent PLA, a molecular weight of 57066.9 g / mol and a temperature melting of 120 ° C. The situation had used in the polymerization of fermented lactic acid after achieving the best conditions for the scientific lactic acid polymerization, namely at a lactic acid mass of 40 gr. PLA polymerized lactic acid fermented with rice straw has the characteristics of dark-grey powder with a molecular weight of 2310.86 g / mole and a temperature melting of 135 ° C.
Kinetics study of enzymatic hydrolysis of Tetraselmis chuii using Valjamae model
Authors: Megawati  , Damayanti A , Putri R D A , Sari P N , Fidyani D
Published: February 2021

The Tetraselmis chuii microalgae have a potential as an alternative raw material for producing bioethanol, because of its low lignin and high carbohydrate content. The purpose of this research is to study the kinetics of enzymatic hydrolysis of Tetraselmis chuii using Valjamae model. This experiment was carried out with a variety of enzymes (cellulase, xylanase, and cellulase-xylanase mixture, enzyme concentrations (10, 20, and 30% w/w), times (10, 20, 30, and 40 min), and temperatures (40 and 45 °C). The results show that the activation energy of hydrolysis using cellulase-xylanase mixture is 27,253 J/mol, xylanase 116,121J/mol, and cellulose 140,914 J/mol. At 45 °C, the concentration of the cellulase-xylanase mixture increased (10, 20, and 30% w/w), the reaction rate constants (0.028, 0.110, and 0.171 1/min) as well as the fractal exponents (0.4, 0.6, and 0.7). Thus, the glucose production rate is higher, where at 40 minutes produces higher yields (23.5, 25.5, 28.5, and 32.5%). In this study, the constant rate of Tetraselmis chuii hydrolysis using cellulase-xylanase mixture at 45 °C is 0.1714 1/min; higher than the one conducted at 40°C which is 0.1454 1/min. The kinetic parameters of the enzymatic hydrolysis are expected to help in bioreactor design.
Fermentation of Tapai and Alcohol Content Released From Tapai
Authors: ul-Haque Dr.Siti Noor Suzila Maqsood , Mueedin NurulSyazwani
Published: February 2021

Tapai is a well-known dessert with slight alcoholic flavour and a sweet sour aroma. Normally, glutinous rice and cassava roots are always used to make Tapa. Both of them are almost similar in taste. However, Tapai needs to be consumed immediately because it is a perishable product. So we need to preserve Tapai by using either natural or synthetic preservatives. In this study, we will review turmeric essential oil as natural preservative to preserve Tapai. If we let it to be fermented for too long, its alcohol content might increase and it may turns the Tapai becomes too alcoholic. So, this review study is conducted to study how to detect alcohol released from Tapai. Different research studies have been done on detecting alcohol released from Tapai by using different kind of methods such as specific-gravity method, refractive index and GC-MS methods. But this review article is focusing more on alcohol biosensor. Other than that, we will observe the changes in biochemical properties of Tapai such as pH and total lactic acid
Oxidation Models of Encapsulated Iron Using Alginate by Gelation Method
Authors: Wardhani D H , Ulya H N , Astuti W I S T , Kumoro A C , Aryanti N
Published: February 2021

Alginate had been used as an additive on many food materials due to its biodegradability and non-toxic properties. As the alginate was extracted from natural sources, it had various properties depending on its source and purification method. In general, alginate has high gelation which hinder its use in high concentration in specific applications. This work aimed to study the effect of alginate modification in protecting oxidation of iron. The modification was conducted using ultrasound. The degraded alginate was applied for encapsulating iron using gelation method. The oxidation profile of the iron was modelled. The result showed that the lower alginate concentration and longer ultrasonication process decreased the alginate ability on protecting the oxidation. After 15 days, the lowest oxidation (8.47%) was able to be suppressed by ultrasonication of 5 % alginate for 30 min. The Kirby model (R2>0.76) was more suitable in describing the oxidation rate from the iron encapsulated by the degraded alginate.
Biodiesel production process without glycerol by-product with base catalyst: effect of reaction time and type of catalyst on kinetic energy and solubility
Authors: Daryono E D , Wardana I N G , Cahyani C , Hamidi N
Published: February 2021

Biodiesel is a renewable energy that is very potential to be produced because it has many advantages compared to diesel fuel. The process of making biodiesel which has so far been carried out is a transesterification process with glycerol byproducts. Glycerol has a low economic value and is usually only disposed of as waste. An alternative process for producing biodiesel with more valuable byproducts is interesterification. The by-product of the interesterification reaction is triacetin which is widely used in the chemical, food and pharmaceutical industries. From the analysis and calculation, the highest FAME yield was 87.18% at reaction temperature 60°C, the molar ratio of palm oil: methyl acetate = 1: 6, reaction time 1 hour, NaOH catalyst, stirring speed of 400 rpm and catalyst mass of 0.5% wt. oil. From the calculation of ChemDraw software for the triglyceride + methyl acetate + NaOH system had an energy kinetic of 2930.8062 kcal/kmol and a dipole moment of 12582.9333 debye, whereas the triglyceride + methyl acetate + KOH system had a kinetic energy of 3140.9573 kcal/kmol and a dipole moment of 9630.3735 debye so that the NaOH catalyst is superior in solubility and the KOH catalyst is superior in reactivity. Biodiesel produced had an acid value of 0.224 mg KOH/g and meets ASTM D664 for a maximum acid value of 0.5 mg KOH/g, and a density of 0.888 g/ml so that meets ASTM D1298 for a density between 0.86 – 0.89 g/ml.
Recent study on TiO2 based Self-Cleaning Coating
Authors: Prawira Rizgyandhaka Artha , Ariyanti Dessy
Published: February 2021

Coating is a way of protecting the surface of the materials as glass, metal, clay, wood, and cementitious from pollutant, dust. self-cleaning coating can be achieved by modifying the surface to have super-hydrophobic, super-hydrophilic, and photocatalytic properties. This paper summarizes the recent studies on TiO2 based self-cleaning coating. The scope of this article is in the mechanism and fabrication route of TiO2 based self-cleaning coating, application technique such as spin coating, spray coating dip coating a nd chemical vapour deposition (CVD) and characterization. Self-cleaning coating can be characterized using many methods in order to determine their quality and feasibility. The characterization of the surface applied by self-cleaning coating can be in the form of numerical data and morphological images such as X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), contact angle, hardness, and scratch resistance are also analysed a nd discussed.
Synthesis Cocamide DEA as Green Surfactant from Virgin Coconut Oil
Authors: Aryanti N , Khoiriyah L , Heny D R , Nafiunisa A , Wardhani D H
Published: February 2021

Petroleum-based surfactants are not biodegradable. In this study, a surfactant made from natural ingredients, namely cocamide DEA. Di-ethanolamine (DEA) is one of the surfactants from non-ionic natural ingredients which has the advantage of being nontoxic, biodegradable, and environmentally friendly. Cocamide DEA is used for the synthesis of a wide variety of heterocyclic compounds and has a wide application in the pharmaceutical, surfactant, polisher and cosmetic industries. Cocamide DEA is obtained from Virgin Coconut Oil (VCO) which contains fatty acids. Manufacture of Cocamide DEA surfactants by the Transesterification-amidase process. Transesterification is the process of chemical transformation of fatty acids reacted with methanol and a catalyst that produces methyl esters. Amidation is the reaction of the formation of amide compounds between di-ethanolamin e and methyl esters (ME). Preparation of surfactant Cocamide DEA from VCO by esterification-amidase process with a ratio of ME:DEA (1:1, 1:1,25, 1:1,5, 1:1,75 1:2) w/w, variations NaOH catalyst (0.25%, 0.5%, 0.75%, 1%, 2% and 3%) and operating temperatures (150°C, 160°C, 170°C, 180°C). The study was conducted on the optimization of Transesterification-Amidation proses, and to analyze the cocamide DEA functional groups with FTIR. The optimization of Transesterification-Amidation proses about ME:DEA ratio, catalyt concentration, and temperature of conversion. The result show that the transesterification-amidase process of cocamide DEA obtained optimum conditions at the ratio ME:DEA = 1:2 w/w, 3% NaOH catalyst concentration on 180°C.
Reduction and Adsorption Mechanism of Chromium Hexavalent in Electroplating Industry Passivation Tank Effluent Using New Linz-Donawits Slag Waste Material.
Authors: Anuar Farah Izatty , Zainuddin N A , Puasa Siti Wahidah
Published: February 2021

Hexavalent chromium Cr(IV) is widely used as electroplating agent to produce a hard, durable coating to a metal with excellent wear and corrosion resistance properties. Yet the effluent of this process needs to be carefully treated as Cr(IV) has been recognized as hazardous, a known carcinogen and mutagen to the human body. Current treatment of Cr(IV) in electroplating industry is by using sodium metabisulfite (SMBS) with a maximum reduction of 100% in a solution of pH 2. Nevertheless, despite the remarkable performance, the application of SMBS as reducing agent generates a massive amount of sludge which eventually will be disposed to the landfill. It also poses detrimental health effects due to the release of hydrogen sulfide (H2S) and sulfur dioxide (SO2) gas. Thus, a less harmful reducing agent was studied to replace SMBS in Cr(IV) reduction process. Linz-Donawitz (LD) slag has been discovered to be a good reducing agent due to the presence of Iron in the form of Fe2+. The characterization of electroplating industrial effluent using ICP-MS shows a highest composition of Chromium which is 1614.6mg/L. Meanwhile, characterization of LD slag shows that the major component is Ferrous (II) Oxide, (FeO) which constitutes 37.2% of the total mass. By using SMBS as reducing agent, 8 ml of 4% v/v SMBS concentration is required to reduce 40% of Cr(IV) in the sample solution. The optimum treatment duration of Cr(IV) using LD slag is found to be 5 minutes and the best pH of the sample solution for optimal reduction rate is 2. In addition, smaller particle size of the LD slag is more advantageous as smaller amount of LD slag is required to completely reduce Cr(IV) concentration in the solution. However, the best particle size is 0.425mm because the reduction rate is more controllable. ORP value at zero Cr(IV) concentration is found to be ±488 mV.
Characterization of Ultrafine Silica Prepared from Rice Husk Ash by Sol-Gel Method
Authors: Qurrota A’yuni Dewi , Djaeni Mohamad , Subagio Agus
Published: February 2021

Rice husk ash that is removed from the combustion process in a furnace has a potential for silica source through the sol-gel process. The experiment was conducted in different concentrations of sodium hydroxide solution of 5.0, 7.5, and 10.0 % w/v in the preparation of the sodium silicate solution. For further observation, different pH values of the gel solution were also examined with values of 1 to 7. Particle Size Analyzer (PSA) has been used for size characterization of samples, while Energy Dispersive X-Ray Spectrophotometer (EDS) was used to determine the composition of the powder. The result shows that for all cases the silica products still contain carbon materials. The different pH values of the silica gel solution exhibit a different physical appearance of the gel. At pH values of 5 to neutral 7, the silica gel is completely formed, while in more acidic conditions there are only precipitates or none of both. Mostly, silica particles were in the size of micrometers with more than 90% in the range of 2-128 µm. The composition characterization showed different percentages of silica and the good result was found at 5.0% of sodium hydroxide solution with a gel solution pH of 7.
Environmental management for small medium electroplating industry, A Cleaner production approach
Authors: Citra A D P , Iswandari H D , Purwanto P
Published: February 2021

Small and medium scale electroplating industry produces a variety of plating products by using hazardous substances as raw materials. The production process at SMI electroplating held manually. Industrial environmental management is conducted by implementing clean production starting from waste prevention, reduction and recycling. Research is conducted in the field through observation and review of actions to reduce process failures and improve them. The success of implementing clean production as an environmental management effort can be extended to other SMIs.
Carbon Capture and Storage (CCS) Network Planning Based on Cost Analysis Using Superstructure Method in Indonesian Central Region
Authors: Dwiputro Mochamad Irfan , Nawasanjani Aufal , Renanto  , Juwari  , Anugraha Rendra Panca
Published: February 2021

Today global warming is a serious threat to living things and the earth, according to WMO, 2019 is the second hottest year after 2016. The average temperature for the last 10 years has reached its highest point. CCS technology is a series of activities that start from capturing CO2 from sources of CO2 emissions, namely the industrial sector and electricity generation. After being captured, CO2 is transported through pipelines or ships to the CO2 storage location in the appropriate storage, it can be geolocical or ocean storage. Each CCS project will use the most suitable method to transport CO2 and pay attention to planning, health and safety regulations. These problems can be overcome by a method, a Superstructure method. A problem with CCS may occur when the source and sink locations are not necessarily in a single region, so it is possible that the CCS process can occur in a multi-region where the source and sink locations are far apart and with many regions. The development of multi-region studies was carried out in this research, namely with the boundaries of the regions of Kalimantan, Sulawesi and East Java with a total of 4 sources and 2 sinks. Development is carried out by making mass transfer scenarios using superstructure method and cost calculations based on Total Annual Cost (TAC) then optimized with optimization software to get the minimum cost. In this study, the optimum CCS network has been determined in Kalimantan, Sulawesi and East Java regions with specific TAC US$ 11,126,782.2/Mt.
Synthesis of Sodium Ligno Sulfonate (SLS) Surfactant from Black Liquor Waste and The Potential Test for EOR in Ledok Field Cepu
Authors: Priyanto Slamet , Dasilva Teodora , Anggara Berdi Bayu , Triyahdiyani Nazila , Sudrajat Ronny Windu , Kusworo Tutuk Djoko , Pramudono Bambang , Untoro Edi , Ratu Puspa
Published: February 2021

Chemical injection in Enhanced Oil Recovery (EOR) with surfactants is known to reduce the value of Interfacial Tension (IFT) of oil and water which can increase oil mobility. EOR has been considered a promising technology to increase national oil production through the revitalization of existing wells in Indonesia, particularly in the Ledok field, Cepu. This study aims to test core flooding on a laboratory scale with EOR surfactant from biomass waste pulp industry, Black Liquor, from Sodium Lignosulfonate (SLS) on porous sandstone media. SLS is produced from lignin which is isolated from Black Liquor waste. In this study, crude oil from Ledok, Cepu, Central Java was used which was characterized first. To determine the effectiveness of surfactant performance before core flooding, several tests such as water stability test, IFT test, CMC (Critical Miselization Concentration) test, and filtration test have been carried out. For the core flooding test, a 1.5% surfactant concentration is injected continuously at 70°C. The core flooding results show that the compatibility test shows that SLS is compatible with Ledok’s natural formation water. Filtration tests show that SLS using membrane 42 produces larger FR solutions. The core flooding test results showed the best reservoir temperature for SLS surfactants was formulated at 70°C with a recovery of 87%. Therefore, the results show that SLS surfactants show promising results for sandstone media. Important for this research is the hydrodynamic study, studying the correlation flow rate of 4.06 Cm/sec, giving the Reynold value in the best porous medium of 0.3, and the best yield of 75% w/w.
Disposal of Waste Communal in Region of Flow River on Settlement Solid Population
Authors: Sari Yenita Sandra , Anggoro Didi Dwi , Sunoko Henna Rya , Ozel Cenap
Published: February 2021

Changes that occur in housing development will change the zone that should be green open space its function to become a dense residential area. The purpose of this research is to find out how the physical condition of the toilet facilities sanitation development program for the community by the Bandung City government, such as what is the domestic waste disposal system residents, as well as to conclude how much community involvement in protecting the watersheds around the facility is also a communal toilet facility. The parameters used are the physical condition of the toilet, the existence of a septic tank, the use of a watershed, and the level of concern of the community using communal toilet facilities. This research is expected to be an evaluation material for the construction of community sanitation facilities in densely populated areas. In densely populated cities need public toilets. However, due to the lack of community participation, the condition of the facilities became damaged, dirty, and not maintained. The facility has become unsuitable for sanitation; squad latrine models are more widely used. The septic tank, which is supposed to be a waste collection facility, turns out that most domestic waste is discharged into the river through pipes. This is very unhealthy, causing pollution in watersheds. To make a government policy made that disposing of household waste from public toilets with pipes is prohibited because it causes the effects of river basin pollution, posing public health risks.
A Comprehensive Review on Hazard Analysis and Critical Point (HACCP): A Case of Lumpia Semarang
Authors: Suherman Suherman , Alhanif Misbahudin , Purwati Dwi , Hapsari Farida Diyah , Dasilva Teodora , Mohammed Omar Ali
Published: February 2021

Indonesia is a country rich in diversity of food types. One of them is Lumpia, which is a typical Semarang food. In this study, the analysis of HACCP in the production of Lumpia has comprehensively explained. The writing method used is a literature review and visualization of information from various types of literature. The analysis carried out in this study consists of 2 steps, namely the analysis of potential hazards and the implementation phase of HACCP, which consists of forming a HACCP team with internal and external recruitment systems, explaining product specifications, determining flow charts by recording the entire process from receiving raw materials to products. Besides, potential hazards in raw materials and additives have also analyzed. The results showed that Lumpia Semarang had implemented HACCP application rules very well, and its products are very safe for consumption. Lumpia Semarang needs to improve the rules for proper processing, especially in the provision of sanitation facilities and material preparation. In addition, the acceptance of raw materials and frying are two critical stages that have high contamination potential. With this study, it expected that the Lumpia production process, which included in the critical stages, could run well and safely, to produce healthy products for consumption.
Characteristics of Biodegradable Foam (Bio-foam) Made from Cassava Flour and Corn Fiber
Authors: Sumardiono S , Pudjihastuti I , Amalia R , Yudanto Y A
Published: February 2021

Plastic in the form of Styrofoam is a synthetic polymer material which is very practical in its use. This garbage is very damaging to the environment if it is burned because it produces gases that are dangerous to human respiration. The use of styrofoam must be stopped and do an alternative effort for any eco-friendly packaging materials, namely bio-foam which uses starch as the main raw material. The potential source of starch is tapioca flour, and the main source for fiber is corncob for several reasons including plastics made from starch/biomass which are more easily decomposed by nature and are abundant, also less utilized. This research was conducted with taking fiber from the corncob waste, then mixing it with tapioca, sorbitol, Mg stearate, and PVA. After obtaining the bio-foam, a water absorption test and biodegradability test were carried out. The results of the water absorption test showed that the 1st treatment had the greatest water absorption, exactly at the immersion time in the amount of 15 minutes in 25.45%, while the biodegradability test with soaking time in the soil for 14 days showed that 1st treatment was the most easily degraded by 20.25%.
Synthesis of TiO2/ZnO-Anthocyanin Hybrid Material for Dye Sensitized Solar Cell (DSSC)
Authors: Alfanaar Rokiy , Elim Philip Estera , Yuniati Yuyun , Kusuma Heri Septya , Mahfud Mahfud
Published: February 2021

Hybrid materials are composed of materials that have broad spectra absorption and can be added to other materials that improve their spectrum absorption. The characteristics of hybrid materials are the same characteristics as their constituent materials. When hybrid materials were added to organic compounds which combined with semiconductors, they can be used as photovoltaic applications. One of the most widely hybrid material research developments is its use as the solar cell. This research focused on TiO2/ZnO hybrid materials synthesis combined with anthocyanin as a pigment to determine the characteristics of the hybrid material obtained. In this research is to find the extent to which method applied that determines the success of the targeted hybrid materials formation. In the synthesis process for various ratios, TiO2and ZnO have been formed a composite material which shown by diffractogram of characteristic peaks of TiO2and ZnO and vibrations of Zn-O-Ti detected in FTIR spectra. Testing hybrid materials by using FTIR showed a C=O vibration of anthocyanin in material hybrid TiO2/ZnO-anthocyanin, than quality testing of hybrid materials was carried out using the DR UV-Vis instrument and was proved by enhancement of band gap energy between 3.2 to 3.3 eV
Effect of solution pH and conductivity on nitrate synthesis by air contact glow discharge electrolysis method
Authors: Harianingsih  , Farisah S , Saksono N
Published: February 2021

This study aims to determine the effect of pH of the solution and conductivity on the yield of nitrates formed. The method is carried out by plasma electrolysis made from air injection. The electrolyte solution used is a mixture of K2HPO4 and K2SO4. The pH condition of the solution is getting longer decreasing also has an effect due to acidic nitrate ions which are more formed if dissolved in water. If the condition of the solution the more acidic, the absorption power of NO2 gas formed in the solution to to NO3 will decrease further, so that over time resulting in the production of nitrates in the solution will decrease. The research results showed that for 120 minutes the processing time was large The pH decreases due to the formation of acidic nitrates. Decreased pH can also be caused by H2O2 production. In minute 0 to minute 5, a significant decrease in pH of 2.99. This is due to accretion nitrate product for 5 minutes the process is very significant that is equal to 1277 ppm. While the decrease in pH at minute 5 to minute 120 is less significant, where the pH decreases around 0.09 to 0.02 due to increase nitrate products are not as large as 5 minutes of processing time. Then, the more acidic the solution causes nitrate production to decrease. In acidic conditions, absorption of NO2 gas formed in the solution to be converted to NO3 will decrease. The concentration of an electrolyte solution affects the conductivity of a solution, where the higher the concentration of an electrolyte solution, the conductivity of a solution will also be even greater. The amount of conductivity will affect the speed at which a plasma is formed.
Spectroscopic of Radicals Formed and Nitrate Production by Contact Glow Discharge Air Plasma Electrolysis
Authors: Harianingsih  , Karamah E F , Saksono N
Published: February 2021

This research’s aims to determine the hydroxyl radicals formed and the production of liquid nitrate in the nitrate synthesis process using plasma electrolysis. Nitrate synthesis has been carried out by various methods including Haber Bosch nitrogen fixation. The synthesis of Haber Bosch nitrate actually causes high gas emissions and is not environmentally friendly. This has led to the synthesis of nitrate which does not cause emissions and is environmentally friendly, namely by plasma electrolysis. The methodology used in plasma electrolysis to produce liquid nitrate fertilizer, by injecting air into the tungsten anode and K2SO4electrolyte. The hydroxyl analysis formed was carried out by looking at the IR spectrum measured using FTIR spectroscopy at an absorption band of 500 cm−1to 4000 cm−1. Analysis of the nitrates formed was carried out using a UV-VIS spectrophotometer. The results obtained were that at t = 10 minutes OH and NH3 radicals were formed at a wavelength of 3331.47 cm-1 and 1634.63 cm-1. The nitrate produced at 0.02 M K2SO4with an airflow rate of 0.2 lpm resulted in an optimal nitrate of 269.12 ppm with an energy consumption of 82.95 kJ/mmol and a yield of 21.7% mol.
Long-term Planning of the Fuel System in Indonesia using Optimization
Authors: Najma  , Purwanto Widodo Wahyu
Published: February 2021

Biofuel has been considered as an option to substitute petroleum fuels and reduce dependence of fossil fuel importation and greenhouse gasess emissions. Current Indonesia’s biofuel blending mandates are cannot achieved due to technical, price and financial aspects. The objectives of the study are to obtain the optimum fuel supply mix by considering the fuel quality standard, production capacity and resource availability. Long-term fuel system optimization by minimum total system cost up to 2050 is carried out using TIMES-VEDA. The results showed that if goverment does not upgrade the quality of diesel up to EURO 4 and adapted EURO fuel specification with adjustment, the optimal fuel supply mix are FAME 50%-Diesel 50% in 2020-2030 and mix of FAME 47%-HVOSMR 53% in 2035-2050. For adapted EURO specification with adjustment except the sulphur content has fuel supply mix of HVOSMR 30%-Diesel 70% in 2020, FAME 20%-Diesel 80% for 2025-2030 and FAME 47%-HVOSMR 53% for 2035-2050. For gasoline, the optimum supply mix is Ethanol 5%-Gasoline 95% in 2020 and Ethanol-Ethanol2G 20%-Gasoline 80% in the 2025-2050. The utilization of biofuels can reduce the diesel and gasoline consumption for about 67-79% and 19% and reduce carbon intensity by 65-78% and 27%, respectively.
Development of Natural Gas Infrastructure to Enhance National Energy Security in Indonesia
Authors: Sugiyono Agus , Adiarso
Published: February 2021

The current use of energy in Indonesia highly still depends on fossil-derived energy. Thus, policies to reduce the use of fossil energy towards the use of new and renewable energy (NRE), which is more environmentally friendly, receive great concern. The government encourages the use of low-carbon technology following up the Paris Agreement to reduce greenhouse gas (GHG) emissions by 29% (without assistance) and by 41% (with international assistance) under Business as Usual (BAU) by 2030. However, accelerating the utilization of renewable energy still faces some obstacles because the economic price of NRE is still more expensive than that of fossil energy. The most likely transition policy is to substitute the use of oil and fuel to natural gas through improving natural gas infrastructure. This transition is following the Sustainable Development Goal (SDG) which guides the achievement of global goals until 2030, namely to ensure access to affordable, reliable, sustainable, and modern energy for all. The development of natural gas infrastructure is currently in an early stage (point to point scheme) and is expected to develop into a hub and spoke scheme towards multiple networks. The more developed infrastructure will further enhance national energy security in the long run.
Pinch Analysis For Styrene Production With Lummus/UOP Smart SM Technology
Authors: Buchori Luqman , Putri Farah Marda Yesica
Published: February 2021

Styrene is an organic compound used for the synthesis of polymers, co-polymers, and rubber. Generally, the reaction to form styrene comes from the dehydrogenation of ethylbenzene. This reaction occurs when the compound is in the vapor phase and is endothermic. One of the technologies for ethylbenzene dehydrogenation is Lummus/UOP Smart SM. This technology uses oxygen to heat the reaction and makes the hydrogen disappear, so the reacting reaches the highest ethylbenzene conversion. The focus of this research was pinch analysis on Lummus/UOP Smart SM. The first step in pinch analysis is data extraction. An alternative is to perform pinch analysis with a composite curve, problem table, shifted composite curve, and grand composite curve. Then is continued to create a design Heat Exchanger Network (HEN). The application of pinch analysis to evaluate heating duty, cooling duty, Maximum Energy Recovery (MER), and determine the exact HEN for optimal energy. In this research, the integration of the process showed not optimal results, especially in cooling duty, because the energy recovery was obtained small, and for heating duty saved about 14%.
Simulation of Scale-up Criteria for Side-entry Stirred Tank in Laboratory Scale
Authors: Fathonah N N , Madhania S , Nurtono T , Winardi S
Published: February 2021

The hydrodynamics in side-entry stirred tanks with similar geometry ratio were studied using Computational Fluid Dynamics (CFD) simulation methods. Scale up is done using a flat bottomed cylindrical side-entry stirred tank with diameter D=0.4 m (T40) and D=0.6 m (T60) in a laboratory scale. The type of stirrer is a commercial three-blade marine propeller with a ratio propeller to tank diameter d/D = 0.1. The effect of the constant propeller rotational speed (N) and constant tip speed (utip
) is evaluated on the pumping capacity and fluid velocity profile in the discharge stream area as well as the flow pattern in the whole tank. Flow patterns are a form of fluid behavior that is easily changed when there are operating conditions in the tank varying, for example when the propeller speed is changed. Considered from the effectiveness of mixing performance, the scale-up criteria similar geometry to the constant N is more beneficial. Visually shows that in the same time span the flow pattern on the T60 is more able to reach the entire tank area. The stagnant area is not visible, whereas in T40 there is still a stagnant flow area in the upper left corner of the tank. However, constant N cannot be used as a reference for scale-up of side-entry stirred tank into a larger scale. Because the phenomenon changes quite dramatically which is caused by a change in propeller diameter. Meanwhile constant utip
gives results that are closer to T40 and T60 in the flow pattern and the distribution of velocity in the discharge stream. So for side-entry stirred tank that has a similar geometry, scale-up criteria with constant utip
is more appropriate to be applied.
Preliminary Study of Slow Pyrolysis for Banana Peel Biomass in Tube Chamber based on Computational Fluid Dynamics
Authors: Triwibowo B , Rengga W D P
Published: February 2021

Dry banana peel as a biomass can be converted towards bio-char using slow pyrolysis methods. The tube chamber that used where slow pyrolysis occur must be in relatively uniform temperature at to ensure the condition are fulfilled in the process. Computational Fluid Dynamics (CFD) method applied to estimate the temperature distribution inside the tube chamber and time needed for the uniformity of temperature is achieved. The tube chamber dimension is 36.5 cm of height with 7.7 cm diameters. The grid generation process performed for the chamber using full hexahedral cell with average orthogonal quality close to 1 that indicated excellent mesh. The observation plane placed right in the middle of tube chamber axially where 6 observation points was placed to observe the change of temperature over time. The simulation process take place in transient regime where the temperature change overtime. The heating sources with heat flux entering uniform in whole outer surface as the wall temperature will peak at 923 K. The heat balance and P1 radiation method was used to obtain the temperature distribution. The simulation results showed a good agreement compared to the experiments. The distribution temperature showed that minimum temperature for pyrolysis process (650°C) already achieved in all of the region. The uniformity of temperature itself achieved after the surfaces of tube chamber reached 650°C for more than 200 seconds.