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Nitrogen is the most important substance in fertilizer to produce high quality harvest. Nitrogen, which comes from the air, can formed as ammonia and nitrate in fertilizer. In industry, the most common fertilizer contain ammonia not nitrate because of its production process easiness compared to nitrate. Ammonia has fertilization efficiency 40% and nitrate has fertilization efficiency 60%. Industrial fertilizer production process nowadays, ammonia synthesis which called Haber-Bosch process, still not environmental friendly and also consume high energy. Environmental friendly and lower energy process is needed to produce fertilizer. Some study related to nitrogen fixation to produce fertilizer has been made including plasma electrolysis method. Plasma electrolysis is an effective method to fix nitrogen from the air because of its ability to produce OH radicals and other radicals to break the N2 bound to produce nitrate with lower energy consumption compared to Haber-Bosch process. This method is implemented in batch reactor with variation of anode depth. This study has proven can produce nitrate up to 1,200 ppm in condition power 800 watt, anode depth 1.5-3.5 cm and Na2SO4 electrolyte concentration 0.02 M.

Driven by the exacerbating urbanization and population, there has been a shoot up in the global energy demand over the past few years. The technological exploration efforts in the field of biofuels have proven to be a promising alternative to the slumping fossil reserves. The main aim of this work is to inspect the potential of palm oil as a biofuel with aluminum oxide nanoparticles as an additive in it. The experimental work was carried out on a single-cylinder four-stroke CI engine running at a constant speed of 1500 rpm at varying loads using palm oil biodiesel blends and the emissions and performance parameters were compared with that of neat diesel. The results concluded a significant increase in BTE with increase in alumina concentration in the blend owing to catalytic behavior of alumina which accelerates the combustion process. Furthermore, reductions in HC and CO emissions were also recorded.

Recently, there has been considerable attention in the development of biodegradable plastic. Our current use and disposal of synthetic-based conventional plastics caused high rates of land-fill problems because of its persistence in the environment. Many renewable resources have been used as a source of starch and cellulose as bioplastic constituents. One of the most available biomasses that have not been explored is water hyacinth (Eichornia crassipes). In the present study, we investigated the fabrication of biodegradable plastic made with a matrix of 3% and 5% mixture of starch and cellulose extracted from water hyacinth in different weight ratios of 10:0, 9:1, 8:2, and 7:3. The addition of water hyacinth cellulose was purposed as a reinforcing agent to improve the performances of the starch bioplastics. Chitosan with a matrix of 1% was also added to improve the mechanical function of starch bioplastic. There were two main steps performed to isolate water hyacinth cellulose, i.e., bleaching and alkali treatment. The chemical and physical characteristics of starch-based bioplastics and their composites were then analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Moreover, the tensile strength and bioplastic degradation tests were also conducted to study the performance and biodegradability. The FTIR data shows that the functional group’s absorption revealed corresponds to the pure cellulose indicating the successful cellulose isolation from water hyacinth. The tensile strength of bioplastic starch- chitosan increases with the addition of water hyacinth cellulose. The improvement of the physical properties of bioplastic starch was achieved through the addition of chitosan and water hyacinth. The mixture of starch-chitosan combined with water hyacinth cellulose produces environmentally friendly bioplastics shown by the increased mechanical and physical properties compared to starch-alone bioplastic.

The concept of liquid waste describes phenol compounds as dangerous pollutants because of the toxicity they confer, corrosion and carcinogenicity. They are actually found in many industrial wastewaters and widely studied because of its adverse effects on the environment. The idea behind this study was due to the existence of significant weaknesses in conventional processing to degrade or remove phenol compounds in industrial wastewater hence necessitating the use of the ozonation technology. This research further aims to evaluate the performance of this technique in multiple injection columns, with or without the use of catalysts (e.g. Fe), in the degradation of phenolic wastewater. The process involved the variation of wastewater discharged (255, 405, 495) mL/min, air flow rate (8, 10, 12) L/min and the amount of the catalyst in weight (50, 100, 200) g to be investigated. Furthermore, the trend of decreasing phenol and COD levels was observed, using a UV-vis spectrophotometer. The results of this study indicate the degradation process with and without catalytic ozonation, extracted phenol up to 99.12% and 99.48% respectively, while the amount of COD reduced were 50.72% and 77.69%. The optimum condition for the treatment process was obtained at pH 12 with an air and wastewater flow rate of 10 L/min and 0.495 L/min respectively in non-catalyzed ozonation method. Furthermore, the use of Fe-based catalysts negatively affected the performance of the process as their presence seems to overload the performance of the ozonation, thereby serving as an inhibitor of phenol oxidation.

Vertical sub surface flow constructed wetland systems for waste water treatment is effective, low cost and a sustainable alternative for conventional waste water treatment technology. The removal of pollutants like BOD, COD and pH in these systems depends on physical, chemical and biological processes that naturally occur in wetlands and areas associated with vegetation, sediment and their microbial communities. In the current work it has been intended to treat textile effluents using sub surface flow constructed wetlands. The experimental setup was constructed using an acrylic tube. Adsorbents like eggshells, gravels, wood husk and activated charcoal were used for the adsorption of pollutants and were filled in the acrylic tube. Escherichia Coli was used for the digestion of organic matters and the plant species – Canna Indica was grown on the surface of the constructed wetland. The BOD and COD removal efficiencies were greater than 40%.

Biomass pretreatment is the most important yet challenging process in biofuel production, with the aim of making part of the biomass more accessible for further treatment. There are four fundamental types of pretreatment techniques employed for bioethanol production: physical, chemical, physicochemical, and biological. Wet oxidation (WO) in fact is known to be one of the most effective pretreatments to liberate more cellulose from lignocellulosic material by heating, in purpose of reducing acid usage in the bioethanol process. The effect of two different conditions of WO pretreatment on fractionation cassava peels, Ulva algae, and water hyacinth was investigated. WO resulted in an increase of carbohydrate content of lignocellulosic residues as a result of the solubilization of cellulose and hemicellulose. The highest carbohydrate content of 1.5g/L was obtained in the pretreatment at 125°C, 45 min, 1.5 bar pH3 for water hyacinth. The pretreatment efficiency was 95%. Changing the pretreatment operating conditions to 130°C, 75 min, 1.8 bar and pH1 allowed to yield high carbohydrate from cassava peel and Ulva algae in respective proportion of 2.38g/L and 1.83 g/L. The WO efficiency was respectively 63% and 95% for cassava peels and Ulva algae. Ethanol yields in respective proportion of 0.26 g/l; 0.31 g/l and 0.2 g/l from Ulva algae, cassava peel and water hyacinth showed the optimum condition of Neurospora.Sp enzymatic convertibility of glucose to ethanol.

Textile industries has become one of the most important sectors in the industrially developed world. Textile dyeing process consumes large amount of water for processing the raw materials along with different chemicals and fixing agents. The effluent coming out of dyeing unit contains huge amount of organic and inorganic pollutants found to be unfit for recycle purposes and cannot be directly drained into the environment. There are many treatment methods available for treating the effluent water coming out of Textile mills. One of the conventional methods now followed is zero liquid discharge (ZLD) by which more than 90% of water is treated and reused by the industry either for processing or converted into steam and about 10% was stored in the form of sludge which shows no sign for reusability. Though the ZLD process looks attractive and efficient, it involves huge amount of capital and operating cost in the likes of evaporators, crystallizer and ATFD (dryer). It was also found that ZLD contributes significantly to carbon footprint which results in global warming. In order to find a feasible solution for the above mentioned problem we have formulated and experimented a novel technique comprises of packed bed zeolite and ozonation process. We studied the characteristics such as pH, color, TDS, TSS, hardness, turbidity of the treated water and compared it with the dye bath feed water characteristics. We concluded our study by dyeing the fabric with treated RO brine by our novel technique. The results show that we can reuse the treated RO brine for dyeing process enrooting the conventional ZLD process.

An experimental research of the process of thermolysis of rubber waste at a steam temperature of 500° C was conducted. The characteristics of the obtained ash residue (carbon) in an amount of 33.8 wt.% partially meet the requirements of ISO 1867-75.6. and are comparable with the grade of carbon black P324. These characteristics include the specific surface (80 m2/ g) and the pH of the liquid suspension (7.84). At the same time, high value of the ash residue (18.44 wt.%) and sulfur (over 2 wt.%) was recorded in the obtained material. Elemental analysis of the ash showed a high content of Zn (56%) and Si (11%).

One of the potential resources of biomass in Indonesia is from palm oil. By the massive amount of waste palm oil, transformation wastes into high valuable material such as bio-fuel become an answer to solve the problem in waste treatment. A transformation of waste to bio-fuel becomes the main target to fulfil energy demand in transportation sector in Indonesia. By producing bio-fuel a bio chemical is also obtained to increase the added value material from the palm oil waste. The objective of this study is to make a model projection for the palm oil plantation in Indonesia and identify the potential biomass feedstock from oil palm process to produce bio-fuel and bio-chemical product by evaluating several parameters such as: technical, supply, economic, environment, bio-polymer composition, etc. An analysis model is needed to determine the potential of palm oil waste based on its capacity and the quality of bio-fuel. The selection type of palm oil waste will be analysed by using Analytic Hierarchy Process (AHP). The type of oil palm waste is derived by using a set of pairwise comparisons to obtain the weight of importance in the decision criteria and relative performance measures. The projection based on the model showed an increase of plantation area that proportional to the population of palm oil tree with growth rate of 6% per year. The composition of plantation area of palm oil is dominated by the group age 3-7 with 26% share percentage. The results by Analytical Hierarchy Process (AHP) showed that the best selection of palm oil waste is empty fruit bunch (EFB) due to its availability, production cost and yield.

In nickel ore smelting, ferronickel slags is one of the outcome from the process. Further utilization of valuable elements in it needs to be processed. In this research, further utilization of the valuable elements is done by pyrometallurgy process where palm kernel shell charcoal was used as reductor. Palm kernel shell charcoal is a biomass fuel, with a very low ash and sulphur contents, therefore it will not release a harmful gases and greenhouse gases into the environment. The pyrometallurgy process is done by heating the ferronickel slag size #200 mesh using furnace carbolite with the mass ratio of the palm kernel shell are 5%, 10%, 15%, 20% respectively and the addition of sodium chloride 10% with operating temperature at 1000°C for 60 min. The result of the reduction then follows with magnetic separation. The result was tested with AAS and XRD, and it showed the content of nickel and iron are increased up tp the optimum point and then decreased, as the ratio of palm kernel shell charcoal increased. Based on the result, optimal parameter for nickel content is obtained by 15% palm kernel shell charcoal at 1000°C for 60 min where the concentrate is 0.153%. Based on the XRD result, it shows that with the use of palm kernel shell charcoal with the addition of NaCl can help to break the complex compounds that made the enhancement of valueable metals are hard in the first place, and can also reduce the oxide compound that is contained on the nickel slag.

The use of composites are being increased day by day. There many types of composites like mud building bricks, concrete and reinforced concrete, fiberglass, natural composites. Natural composites are the one which are made of plant derived fiber with polymeric matrix. The natural fiber consists of sisal, jute, hemp, banana leaf fibers, bamboo, wheat straw, coir fiber, grass reeds, wood fiber, rice husk, wheat, prosopis julifora, oats, cane and many other fibrous materials. They have a vast application and are eco-friendly. Natural fiber reduces both cost and density when compared to other types of fibers which are available. The alternative source of synthetic fibers are natural fibers which are renewable in nature, cost effective and also causes no harm to the environment. In this the uses and applications of prosopis juliflora and coir fiber natural composites are discussed.

Water filter has been made to improve well water quality by using filtration concept in which activated carbon from cocoa rind waste and clay was used. The filter was made by varying the composition of cocoa rind waste and clay in activated carbon at the ratios of 85%:15%, 80%:20%, 75%:25%, 70%:30% and 65%:35%. The combustion temperature was varied at 200°C, 230°C, 260°C, 290°C and 320°C. Then it was molded by using mold and press conventional technique. The characterization results showed optimum composition was reached at 65%:35% ratios under 320°C combustion where the absorbance and porosity of water filter were at 86% and 52.38% respectively. Whereas density of 0.617 g/cm3 and 0.00514 MPa compressive strength were obtained from 85%:15% composition at 200°C combustion temperature. The performance test for the filter in purifying well water gave 3.2 NTU for turbidity, 7 TCU for color, 338 µS/cm conductivity, 6.7 pH level and Fe content of 1.0 mg/L. The analysis done showed that the water filtered has met the standard quality of clean water.

The use of magnetite nanoparticles to produce magnetic paper has a severe effect on the color of the paper, which is worth searching means to alleviate. Multicore-shell Fe3O4-SiO2 magnetic nanocomposites were synthesized. The nanocomposite powder was dispersed in cellulose pulp and paper was produced by dehydration on a Rapid Kothen machine. The nanocomposite retention efficiency was investigated in correlation with nanocomposite shell thickness, the resinous vs. deciduous fiber content of the cellulose pulp, the long and short fibers’ grinding degree, the cationic starch and polymeric retention agent content of the pulp. The whiteness and magnetization was measured for all paper samples. It was proved that the use of multi-core shell magnetic nanocomposites leads to weaker paper coloring. This effect is enhanced by increasing the polymeric retention agent content of the pulp, in spite of higher composite content.

This paper presents the effect of wastewaters on properties of Portland pozzolana cement (PPC). Fourteen water treatment plants were found out in the Narasaraopet municipality region in Guntur district, Andhra Pradesh, India. Approximately, from each plant, between 3500 and 4000 L/day of potable water is selling to consumers. All plants are extracting ground water and treating through Reverse Osmosis (RO) process. During water treatment, plants are discharging approximately 1,00,000 L/day as wastewater in side drains in Narasaraopet municipality. Physical and chemical analysis was carried out on fourteen plants wastewater and distilled water as per producer described in APHA. In the present work, based on the concentrations of constituent’s in wastewater, four typical plants i.e., Narasaraopeta Engineering College (NECWW), Patan Khasim Charitable Trust (PKTWW), Mahmadh Khasim Charitable Trust (MKTWW) and Amara (ARWW) were considered. The performance of four plants wastewater on physical properties i.e., setting times, compressive strength, and flexural strength of Portland pozzolana Cement (PPC) were performed in laboratories and compared same with reference specimens i.e., made with Distilled Water (DW) as mixing water. No significant change was observed in initial and finial setting time but setting times of selected wastewaters were retarded as compared to that of reference water. Almost, no change was observed in 90 days compressive and flexural strengths in four plants wastewaters specimens compared to that of reference water specimens. XRD technique was employed to find out main hydration compounds formed in the process.This paper presents the effect of wastewaters on properties of Portland pozzolana cement (PPC). Fourteen water treatment plants were found out in the Narasaraopet municipality region in Guntur district, Andhra Pradesh, India. Approximately, from each plant, between 3500 and 4000 L/day of potable water is selling to consumers. All plants are extracting ground water and treating through Reverse Osmosis (RO) process. During water treatment, plants are discharging approximately 1,00,000 L/day as wastewater in side drains in Narasaraopet municipality. Physical and chemical analysis was carried out on fourteen plants wastewater and distilled water as per producer described in APHA. In the present work, based on the concentrations of constituent’s in wastewater, four typical plants i.e., Narasaraopeta Engineering College (NECWW), Patan Khasim Charitable Trust (PKTWW), Mahmadh Khasim Charitable Trust (MKTWW) and Amara (ARWW) were considered. The performance of four plants wastewater on physical properties i.e., s...

Aerobic granular sludge technology can be one of the solutions to extend wastewater treatment plant when a limited space is available, besides Sequential Batch Reactor or biofilm carrier media technologies. This paper presents a comparative study between two types of technologies, Sequential Batch Reactor (SBR) and Granular Sequencing Batch Reactor (GSBR), using BioWin simulations based on the designed data of a wastewater treatment plant. Efficiencies of both technologies are studied regarding organic load and nutrients.

Oil palm fronds are one of the most promising agricultural lign ellulosic residues for bioethanol production and for adding value to chemical feedst ks in Indonesia and South Kalimantan. Currently, hydrothermal pre-treatment has attracted a great deal of attention because it only uses chemical-free water, which is a non-toxic, inexpensive, and environmentally friendly method to enhance enzymatic digestibility in the production of fermentable sugars. In this study, oil palm fronds were treated at temperatures ranging from 170 to 210°C for 30 minutes in a batch aut lave. The effect of the temperature and time of hydrothermal pre-treatment on the characteristics of the oil palm fronds and the amount of reducing sugar was expressed as a severity factor (log R0). Furthermore, after the hydrothermal pr ess the changes in the mass loss, color of substrates, and the pH of filtrate were evaluated. From these results, the mass loss and pH indicated that the optimum severity factor for hydrothermal treatment was 4.72. Additionally, the alteration to the oil palm frond structure was confirmed by Fourier Transform Infrared (FTIR) spectroscopy. Finally, 48.8% (w/v) fermentable sugars were obtained from enzymatic hydrolysis using cellulase enzyme at the newly determined maximum severity factor of 4.72.At the request of all authors of the paper an updated version of this article was published on 29 November 2018. The original version supplied to AIP Publishing contained incorrect corresponding author information; the corresponding author is only sunardi@ulm.ac.id, and many typographical errors. These errors have been corrected in the updated and re-published article.

This paper reports results of an investigation on the blended BWA-FA geopolymer mortars prepared by the inclusion of biomass wood ash (BWA) as a partial replacement material for fly ash (FA). The blended mortar systems were prepared at three replacement ratios of FA by BWA of 5%, 15% and 25% by binder mass. The engineering properties of compressive strength, water absorption and total porosity measurements obtained at different ageing of 3, 7 and 28 days, were used to assess the blended systems against a control mortar mix containing 100% FA. The results showed that the inclusion of BWA up to 15% resulted in higher strength and durability characteristics than the control mix at age of 3 and 7 days. However, at age of 28 days, the geopolymer containing 10% BWA of the total binder was the only blended mixture exhibited higher compressive strength and lower total porosity than the control mix.

A sensitive dip test strip for detection of formalin (HCHO) in tofu samples based on immobilized pararosaniline (PR) has been developed. The test strip has been fabricated by immobilizing PR reagent on filter paper. By using image color analysis (ImageJ) as the average of ΔRGB value as color sensor response, the analytical parameters are obtained from an area of the sensing zone of the test strip using digital output of the color scanner. By using this scanometric method, it is possible to determine HCHO as low as 0.05 mg/L with the concentration range of 2-80 mg/L and the response time of 3 minutes. The reproducibility was found to be 8.04% (RSD) for good recovery. The test strip has been successfully applied to detect formaldehyde in tofu samples, and the results show in good agreement with the Nash method using UV/vis spectrophotometry.

The paper focuses on the development of a low-cost biogas filtration system for alternating current generator to achieve higher efficiency in terms of power production. A raw biogas energy comprises of 57% combustible element and 43% non-combustible elements containing carbon dioxide (36%), water vapor (5%), hydrogen sulfide (0.5%), nitrogen (1%), oxygen (0 – 2%), and ammonia (0 – 1%). The filtration system composes of six stages: stage 1 is the water scrubber filter intended to remove the carbon dioxide and traces of hydrogen sulfide; stage 2 is the silica gel filter intended to reduce the water vapor; stage 3 is the iron sponge filter intended to remove the remaining hydrogen sulfide; stage 4 is the sodium hydroxide solution filter intended to remove the elemental sulfur formed during the interaction of the hydrogen sulfide and the iron sponge and for further removal of carbon dioxide; stage 5 is the silica gel filter intended to further eliminate the water vapor gained in stage 4; and, stage 6 is the activated carbon filter intended to remove the carbon dioxide. The filtration system was able to lower the non-combustible elements by 72% and thus, increasing the combustible element by 54.38%. The unfiltered biogas is capable of generating 16.3 kW while the filtered biogas is capable of generating 18.6 kW. The increased in methane concentration resulted to 14.11% increase in the power output. The outcome resulted to better engine performance in the generation of electricity.

Water treatment is the process to make the water reusable to consumers. There are several process to treat water such as chlorination, sedimentation and filtration. Water filtration is known to separate substance or object in contaminated water. Method of filtration is vary depending on the location of the targeted material whether it is dissolved in the suspended as a solid or fluid. This paper present a preliminary study to constructing a low-cost of water filter by using materials namely coarse aggregates, sand, activated carbon in additional of loofah and coconut fiber. The result was measured by analyzing the water parameter such as, Biochemical Oxygen Demand (BOD), Dissolve Oxygen (DO), turbidity, and colour. The result of raw water and filtered water are characterized according to the National Water Quality Standard (NWQS) for Malaysia. The final results from laboratory experiment showed a good improvement of water parameter during the application of coconut and loofah fiber in water filtration. The BOD5 result for coconut and loofah fiber model show significant improvement from class IV to class I and III.

Indonesia has large areas of cacao (Theobroma cacao L) plantation, which mostly plant by smallholders (94%), inconsequences it produces waste. Wastes are in the form of cacao pods and placenta or pulp, leaves, and twigs. One of the methods used to handle cacao waste is by composting. Research is done by adding activators to accelerate the composting. Activators used are Effective Microorganism 4 (EM4), Beyonic Startmix biological organic fertilizer and Suburnik liquid organic fertilizer. Cacao waste used is from smallholder cacao plantation located in Pangadegan village, Rancakalong Sub-district, Sumedang Regency of Indonesia. Composting is done in a composter made of vats with a capacity of 50 liters. Monitored parameters include composting temperature, ambient temperature. The testing of compost products includes chemical and physical quality testing. Chemical quality tests include pH value, moisture content, C-organic, total Nitrogen, C/N ratio, P2O5, K2O, ash content, CaO, MgO, S, Fe, Cu, B, Al. Physical quality tests include color and odor. The test results showed that the chemical and physical quality of the compost in the three activator materials used to produce compost that is not significantly different with the quality that meets the criteria of compost quality according to Indonesian National Standard number 19-7-30-2004. Beyonic Startmix activator is the best activator, followed by EM4 and Suburnik.

Food waste is one of the wastes that is being generated about every day. It would be a waste if the generated waste is ignored, neglected and just being disposed of without using the benefits that are in the food waste. The aim of this study is to find the best way for food waste recovery by using effective microbes (EM). There are three different parameters used in this study. The parameters are the method of drying the food wastes, the presence of Effective Microbes (EM) after the drying of food wastes and the addition of wheat pollard. An effective microbe is a combination of anaerobic microorganisms in a liquid. The effective microbe is activated by mixing the EM 1 with molasses and water with the ratio of 1:1:20 and is left for a week. Molasses is a thick liquid of sugar from the plant such as sugarcane. The food waste went through three processes for it to be recovered which are drip the food waste leaching water at the designated table, grind the food waste and lastly dry it. Before grinding, the coconut pulp was added to the food waste. The food waste is analysed based on four analyses. The four analyses are moisture content, protein analysis, E-coli analysis and Fourier-transform infrared spectroscopy analysis (FTIR). Moisture content was done to analyse the amount of water in the food waste by using the weight before and after the drying process. Two types of drying process were used in this study; drying by oven and conventional fan. Based on moisture content, the best drying method is by using the oven. The result shows that the moisture content is 28% when the sample dried using an oven compared to a conventional fan (51.4%). Protein analysis and E-Coli analysis are conducted to find an amount of protein and E-coli respectively in the sample. Fourier-transform infrared is an analyzing process to observe the absorption spectra of the food.

This paper reports, to the best of our knowledge, the first utilization of non-treatment waste concrete as heterogeneous catalyst to enhance the biodiesel production from waste cooking oil (WCO) using a co-solvent free electrochemical method. The properties of WCO and cooking oil as feedstock as well as the waste concrete and the hydrated cement as catalysts were investigated thoroughly. The effect of catalyst amount and the potency of WCO as feedstock were discussed. Furthermore, we have also performed the comparative study of catalytic activity between waste concrete and hydrated cement, in which the former displays a higher activity. Finally, the waste concrete actively catalyze the biodiesel production using WCO as feedstock with the yield of fatty acid methyl ester (FAME) up to 92.92% under ambient condition using 0.5 wt.% of catalyst, 24:1 of methanol/oil molar ratio, 0.56 wt.% of NaCl (wt. % of oil) at a constant voltage of 9.6 V for 2 hours reaction. Our results show that such waste, nearly no-cost materials are highly potential as catalyst for biodiesel production.

Acacia Mangium and Eucalyptus Pellita had been used as raw material of pulp in Indonesia. In this research 5-year old of the wood were pulped under different active alkali charge varied at 16, 17, 18, 19 and 20% and its effect on pulp yield, pulp viscosity and kappa number was investigated. The cooking was done in a rotating digester Haato 6 chambers and 300 gram of dry mass chips were used, with sulfidity 25%, H-factor 800, temperature 165˚C and ratio between chips and liquid was 1: 3,5. The pulp screened yield indicates that decreased from 53,7 to 52,25% for acacia mangium and 53,0 to 50,6% for eucalyptus pellita when active alkali charge increased. Kappa number decreased from 19,0 to 16,8 for acacia mangium and 16,69 to 13,4 for eucalyptus pellita when active alkali charge increased. The viscosity decreased from 818 to 378 ml/g for acacia mangium and 697 to 426,8 ml/g for eucalyptus pellita when active alkali charge increased.

In this paper, bioreactor was used to simulate the municipal solid waste (MSW) biodegradation process of landfill, tracing and testing trash methanogenic process and characteristics of leachate during anaerobic digestion, exploring the relationship between the two processes, aiming to screen out the indicators that can predict the methane production process of anaerobic digestion, which provides the support for real-time adjustment of technological parameters of MSW anaerobic digestion system and ensures the efficient operation of bioreactor landfill. The results showed that MSW digestion gas production rate constant is 0.0259 1/d, biogas production potential is 61.93 L/kg. The concentration of TN in leachate continued to increase, showing the trend of nitrogen accumulation. “Ammonia poisoning” was an important factor inhibiting waste anaerobic digestion gas production. In the anaerobic digestion system, although pH values of leachate can indicate methane production process to some degree, there are obvious lagging behind, so it cannot be used as indicator alone. The TOC/TN value of leachate has a certain indication on the stability of the methane production system. When TOC/TN value was larger than12, anaerobic digestion system was stable along with normal production of biogas. However, when TOC/TN value was lower than 12, the digestive system is unstable and the gas production is small. In the process of anaerobic digestion, the synthesis and transformation of valeric acid is more active. HAc/HVa changed greatly and had obvious inflection points, from which methane production period can be predicted.

Natural (plant) fibre become main concern for replacing synthetic fibre in product development. There are many application of the natural fibre product such as automotive interior lining, upholstery stuffing, electronic packaging and egg-boxes. Many natural fibre has been explored such as kenaf, flax, hemp, jute, ramie, nettle, sisal, henequen, banana, oil palm EFB, oil palm mesocarp, cotton, coir, cereal straw and bagasse. The most potential natural fibre i.e. kenaf fibre due to high cellulose content (cellulose sources). Therefore, kenaf fibre was challenging to explore in terms of retting process, yarn and composite development. This paper focus on retting process where it was conducted by several chemical agent such as Sodium Hydroxide (NaOH), Sodium Lauryl Sulfate (SLS) and enzymatic with pectinase. NaOH become common chemical agent and 6% of concentration become an optimum parameter for improving flexural, tensile and impact strength.

Hybrid Power Plant, which uses solar energy and in situ fuels such as pure coconut oil (PCO) and pure palm oil (PPaO), could be a solution for electricity problem in remote areas in Indonesia. Comparison of performance, and emissions are discussed and analyzed in this paper. For performance parameter, efficiency of hybrid system averages 7% higher compared with diesel engine. BSFC of diesel engine average value by using PPaO and PCO are 7.2% and 4.7% higher than by using diesel fuel. However, the BSEC average values are 4.5% and 3.3% lower than the diesel fuel. For the emission parameters, average value of CO2 emissions from the hybrid system is 21.7% lower than the diesel engine, but average value of CO emissions is 31% higher compared to diesel engine. Significant differences can be observed at average value of NOx emissions by using PCO and PPaO which are 210% and 117% lower compared to the diesel fuel.

Scarcity in fuel from fossil fuel has led to exploration of potential substitutes from renewable sources. Biodiesel as one of renewable energy sources is identified as cleaner alternative to petroleum fuel. This paper reports on the study of potassium carbonate, K2CO3 sourced from pineapple and orange peels as heterogeneous catalyst for biodiesel production. K2CO3 was produced by drying of fruit peel prior to calcination at temperature ranged from 700°C to 1000°C for 2 to 4 hours. To determine the physicochemical properties of the resulting ash, Fourier transform infrared (FTIR) and Scanning electron microscopy (SEM) analysis were employed for the characterization of the solid. Through FTIR analysis, the presence of carbonate was confirmed while SEM analysis revealed the morphological properties of the catalyst. Biodiesel with highest yield of 95.6% was produced at 60°C, 2.75 wt% of catalyst and 12:1 molar ratio of methanol to oil.

Latex is a yellowish colloidal liquid from rubber trees that can be used for natural rubber production. The latex processing creates quite large volume of wastewater that has very strong odor and high organic content which is suitable for biogas production in providing renewable energy resources. The purpose of this research is to study and optimize the biogas production from latex wastewater using 40 L packed bed anaerobic reactors with support media of bio-balls or called anaerobic filter reactor. Some key parameters of sCOD, pH, and methane gas composition have been observed. The reactor was operated batch for 36 days with or without packing media (bio-balls). The optimum results of sCOD removal was 81,73% and methane gas content of 55.089% using reactor with packing. The anaerobic filter column was used in continuous mode with 2L/day influent that can reach a steady condition within about 20 days and produce up to 95% COD removal.

The rapid dewatering process of wastewater sludge was studied. The effects of two different thickening methods on subsequent conditioning and pressing were compared: gravity thickening and mechanical concentration. The study also investigated the optimal type and the concentration of flocculant added by sludge concentration, which was 0.2%. In terms of mechanical concentration method, under the same formulation of conditioner, the addition of Polyacrylamide(PAM) could significantly promote the dewatering process. Compared with the gravitational sedimentation and the sludge without chemical concentration, the filtration rate and dry-base treatment efficiency of the sludge during pressing were obviously improved, and the moisture content of the sludge cake was reduced.

Biodiesel is one kind of alternative fuel that is renewable, biodegradable, oxygenated, and less polluting. High viscosity, density and lower calorific value are the major drawbacks of biodiesel. To overcome drawbacks of biodiesel, many researches were carried out all over the world by blending biodiesel in different ways with fossil fuel and short chain alcohols as oxygenated additives. Recently, researchers concentrated on long-chain alcohol due to its high cetane number, heating value and oxygen content. From outcomes of many previous studies, the use of long chain alcohols with biodiesel is not covered and concluded completely overall. Because of complete data scarcity, more investigations should be carried out on the use of long chain alcohols. This work investigates the combustion characteristics, performances and emissions of a four-stroke single cylinder direct injection diesel engine fuelled with 2-ethyl 1-hexanol (2-EH) at 5%, 10% and 20% with POME fuel blends as a replacement for fossil fuel. The fuel blends were used and compared with diesel fuel. Fuel blends are experimentally tested at a maximum load of 28 N.m and different engine speeds. Results show that HE5 had lower peak pressure than DF by 1.77% and overall lower CO and NOx emissions than DF by 8.5% and 4.1%.

Corn husks, cobs, and stalks are Indonesian agricultural waste products which are present in abundance. The reusability of these wastes is still limited to traditional applications, such as the base for animal feed, organic fertilizer, or handicrafts. On the other hand, corn - which is belong to the Family Poaceae - is a rich and economic source of naturally occurring silicon dioxide minerals, with size ranging from micrometer to nanometer. Silicon dioxide and its reduced product silicon, recovered from corn waste possess potential application in various fields, ranging from semiconductor, pharmaceutical, catalysis, gas adsorption, to lithium-ion batteries technology. The application depends on its physical, chemical, and electrochemical characteristics. In this work, corn husks, cobs, and stalks are processed through leaching at various HCl concentration, followed by atmospheric decomposition at moderate temperature to obtain silicon dioxide for further suitable application. Morphological characteristic is analyzed by SEM images, crystallinity of silica is investigated by XRD, while possible organic contaminants are detected by FTIR. The result shows that corn husks provide the highest silicon dioxide yield at 2.543 wt.% compared to cobs and stalks obtained from the same condition, which are 0.457 wt.% and 2.030 wt.%, respectively. Powders obtained from corn husks also indicate a higher purity with insignificant metallic or organometallic contaminants, showing closest crystal structure to the mixture of quartz and amorphous silicon dioxide.Corn husks, cobs, and stalks are Indonesian agricultural waste products which are present in abundance. The reusability of these wastes is still limited to traditional applications, such as the base for animal feed, organic fertilizer, or handicrafts. On the other hand, corn - which is belong to the Family Poaceae - is a rich and economic source of naturally occurring silicon dioxide minerals, with size ranging from micrometer to nanometer. Silicon dioxide and its reduced product silicon, recovered from corn waste possess potential application in various fields, ranging from semiconductor, pharmaceutical, catalysis, gas adsorption, to lithium-ion batteries technology. The application depends on its physical, chemical, and electrochemical characteristics. In this work, corn husks, cobs, and stalks are processed through leaching at various HCl concentration, followed by atmospheric decomposition at moderate temperature to obtain silicon dioxide for further suitable application. Morphological characteristic ...

The production of bioethanol from date molasses is one of the effective discoveries in the field of Sustainable development represented in positive exploiting of renewable energies mainly biomass energy. The paucity of ethanol gas at the Sirte University was the stimulator for considering this research. The study was conducted in the chemistry labs at the Sirte University in 2018 to investigate the possibility of producing bioethanol from date molasses determining the effect of different temperature, PH, yeast quantity and fermentation time in molasses on the amount of ethanol produced. Three samples of molasses were taken in different sizes. Bioethanol was indirectly extracted through alcoholic fermentation of date molasses in anaerobic conditions. Because of the lack of a low-pressure distillation device, a normal distillation device was used. The best amount of bioethanol (25ml) was extracted at the largest quantity of yeast (2g), the longest fermentation time (236h), the highest fermentation’s temperature and PH 4.8. Ethanol specifications were examined via qualitative tests.

Emulsions are dispersion systems, where one phase is dispersed in another phase in the presence of an emulsifying agent (surfactant). Emulsion fuel can reduce cylinder peak pressure from the combustion chamber compared to using neat diesel fuel. This research use a single-cylinder diesel engine, operates using water diesel emulsion with water percentage of 30% and 35% by volume and diesel fuel as a comparison. Diesel operates with a speed of 1500 rpm and engine load 1000-4000 watts at 500-watt intervals. The results of research at high load showed that fuel consumption of E30 and E35 increased by 15.5% and 16.6%, thermal efficiency increased by 21% and 35.8% (respectively). Whereas HC and CO emissions increase along with the increase in water percentage.Emulsions are dispersion systems, where one phase is dispersed in another phase in the presence of an emulsifying agent (surfactant). Emulsion fuel can reduce cylinder peak pressure from the combustion chamber compared to using neat diesel fuel. This research use a single-cylinder diesel engine, operates using water diesel emulsion with water percentage of 30% and 35% by volume and diesel fuel as a comparison. Diesel operates with a speed of 1500 rpm and engine load 1000-4000 watts at 500-watt intervals. The results of research at high load showed that fuel consumption of E30 and E35 increased by 15.5% and 16.6%, thermal efficiency increased by 21% and 35.8% (respectively). Whereas HC and CO emissions increase along with the increase in water percentage.

A combined electrocoagulation and mixing process was utilized to treat river water contaminated by textile waste. The electrocoagulation process was carried out in a cylindrical reactor equipped with an impeller and baffles for mixing purposes. Two types of impellers were used, i.e. three-blade propeller and Rushton turbine, to study the influence of the impeller types on the quality of effluent. Three pairs of aluminum (Al) plate electrodes were attached to the reactor as baffles to create turbulence and facilitate proper mixing. The influence of an applied electrical current was also investigated. The experimental results showed that TSS, TDS, BOD, and COD were effectively reduced when using a propeller with an applied current of 15 A. The reduction percentages were 98%, 74%, 57% and 49%, respectively. During 60 minutes of electrocoagulation process, the average mass of the Al electrodes is reduced by 1.7 grams at the operating current of 10 A and 0.6 grams at a current of 15 A. In addition, the pH of effluent was between 7 - 8, which meets the quality standard of effluent wastewater.

Biosurfactants produced by particular bacteria can be applied in petroleum industries to enhance petroleum recovery by lowering the interfacial tension (IFT) between water and oil layers in the res...

Pyrolysis is one of thermolysis technology used to obtain some alternative sources of hydrocarbon energy. It is almost similar with combustion technology, however, without involving oxygen in the combustion process. In addition to renewable resources, the pyrolysis products are substances that are environmentally friendly and have many benefits. The pyrolysis products are such as tar, char and gas. Fuel source of the pyrolysis is derived from renewable resources such as biomass or plant. A macroalgae gracilaria is one of biomass can be used as raw material in the pyrolysis process. It is due to Indonesia has vast waters that have a wide range of aquatic products, so it is appropriate if the macroalgae is used to be a biomass feedstock of pyrolysis. In addition, the ability of macroalgae to breed is very high, so that it makes the macroalgae feedstock will be abundant. The macroalgae chemical composition consists mainly of crude fiber (cellulose, hemicellulose and lignin) of 32.15% hemicellulose, 17.04% cellulose, and 3.05% lignin. The aim of study was to investigate the thermal decomposition of macroalgae expected to produce some substances that can be used as an alternative fuel. In the experiment, the macroalgae samples were dried to reduce the moisture content. Afterwards, it was weighed 400 grams and put in a pyrolizer. The sample was pyrolyzed with variations in temperature of 250°C to 800°C for 3 hours. The results showed that the higher pyrolysis temperature, the less mass and volume char products, and the smaller the char heating values that differ from another biomass research. Meanwhile, an increasing of pyrolysis temperature also causes an increasing of mass and volume tar. The heating values of tar also incline. For the generated gas production, an increasing pyrolysis temperature result an enhancement of gas flow rate.

The Microbial Desalination Cell (MDC) is one of the energy efficient methods to desalinate sea water developed from the Microbial Fuel Cell (MFC) employing the metabolism of microorganisms. In this study, we utilized microorganisms from Universitas Indonesia (UI) lake water as substrate and coconut shell charcoal as bio electrode instead of conventional electrodes. Coconut shell charcoal is known to have good performance capability in MDC system, low price and environmentally friendly. We used sodium percarbonate (NP) that has excellent buffering capability as a catholyte and UI lake water as an anolyte in our MDC system. With this, we could reduce the cost of sea water desalination process and at the same time we could manage to overcome pH imbalance which commonly occur in MDC system. The optimum result of the seawater model desalination after 50 hours was obtained from the MDC system employing NP concentration of 0.15M. The salt removal (SR) was 15.14% with desalination rate (DR) of 0.1876 mmol/hour.

Due to population rapid growth, fertilizer industries have to increase the production to ensure food security causing faster non-renewable resource depletion. However, organic wastewater (cow urine) commonly contains high amount in NH4+ and PO43- is still underutilized and causing eutrophication and unpleasant odour problem. Struvite precipitation, a common technique using for nitrogen and phosphorus recovery from wastewater,is proposed to recover the organic and renewable nutrients sources. Struvite precipitation process for nutrients recovery/removal from waste sources is beneficial not only providing slow-releasing and high-quality fertilizer but also reducing soil and water pollution from rich-nutrients wastewater. This research aimed to utilize the cow urine wastes as the raw material for the struvite precipitation, to determine the influence of the PO43-: Mg2+ concentration, and input flowrate on a continuous reactor to the struvite formation. Struvite was made using continuous method with variation of the PO43-: Mg2+ concentrations ratio of 1:1; 1:2 and 1:4 and the inlet flowrate of 8.2 mL/s and 15.8 mL/s. The results of this study show that the increase of MgCl2 addition and the higher flow rate could increase the P removal efficiency of struvite in reactors. The optimum phosphate removal efficiency at the flow rate of 8.2 mL/s is obtained at 80 mins with the percentage of 54%, while at the flow rate of 15.8 mL/s, 43% of P removal is obtained at 70 mins. The results from the kinetic study in the input flowrate was found that the higher the concentration ratio of PO43- and Mg2+, the greater the value of the reaction rate constant. However, for molar ratio 1:1 of PO43-: Mg2+, the greater the input flow rate, the smaller value of the reaction rate constant was obtained. From this study, it is revealed that the molar ratio of PO43-: Mg2+ and aeration rate affect significantly the struvite precipitation.

Coal is the cheapest and reliable source for power generation, which has the potential to reduce the dependency on natural gas, particularly for Bangladesh, where the natural gas reserve is very limited. Despite numerous studies on gasification from different parts of the world, there has not been a research study on gasification characteristics of Bangladeshi Barapukurian coal (BBC) under state of the art entrained flow condition. Thus, this study aims to investigate the gasification characteristics of Barapukurian bituminous coal using a high-temperature electrically heated entrained flow gasifier under atmospheric pressure.The effect of the partial pressure of the gasification reagent (CO2) on carbon conversion and gas yield was tested by varying the volume percentage of CO2 in N2 between the temperatures of 1000-1400°C. Furthermore, the influence of particle size on carbon conversion and product gases was also examined using industrially relevant particle sizes: 90-106 µm and 250-300 µm. The results show that increasing the temperature and feed CO2 concentrations increase the carbon conversion, though the temperature is found to be the dominant factor. A maximum carbon conversion of 92 % was achieved using ultimate operating conditions of 1400°C and 40% CO2 for particles size: 90-106 µm, while the conversion was only 65% for particle size: 250-300 µm under identical operating conditions. Overall, the yield of CO was increased while the yield of H2 was decreased with increasing temperatures and CO2 concentrations. The maximum yield of CO and H2 was determined to be 0.93 and 0.14 L/g coal respectively using particle size: 90-106 µm, which is 0.88 and 0.12 L/g coal using particle size: 250-300 µm at a temperature of 1200°C under 10% CO2. The main pollutants measured were HCN, NH3 and H2S in the ppm range. The results of this study will provide a baseline data for the industrial scale entrained flow gasification of BBC under CO2 atmosphere.Coal is the cheapest and reliable source for power generation, which has the potential to reduce the dependency on natural gas, particularly for Bangladesh, where the natural gas reserve is very limited. Despite numerous studies on gasification from different parts of the world, there has not been a research study on gasification characteristics of Bangladeshi Barapukurian coal (BBC) under state of the art entrained flow condition. Thus, this study aims to investigate the gasification characteristics of Barapukurian bituminous coal using a high-temperature electrically heated entrained flow gasifier under atmospheric pressure.The effect of the partial pressure of the gasification reagent (CO2) on carbon conversion and gas yield was tested by varying the volume percentage of CO2 in N2 between the temperatures of 1000-1400°C. Furthermore, the influence of particle size on carbon conversion and product gases was also examined using industrially relevant particle sizes: 90-106 µm and 250-300 µm. The results s...

Banana (Musa Paradisiaca) peels are usually considered as wastes and discarded during the processing, which contribute to polluting the environment. Hence this study is evaluating the potential of waste banana peel as powders and applies in the polymer matrix as alternative for future used. Banana peel is used widely because of its nutritional values and its healthy. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms and can be apply in coatings or dental applications. The varieties of ripening of banana peel effects the mechanical, physical and chemical properties of its peel. Several methods are proposed for powder size of cellulose preparation include, hammer mill, grinding and ball milling method. A modification needed for the uniform dispersability of the cellulose powder in polymer matrix which the method will modify the hydrophobicity of hydrogen bonding in cellulose to hydrophilic. They are several of application of cellulose powder in polymer matrix for further used in plastic packaging, as dye removal or dental application used.Banana (Musa Paradisiaca) peels are usually considered as wastes and discarded during the processing, which contribute to polluting the environment. Hence this study is evaluating the potential of waste banana peel as powders and applies in the polymer matrix as alternative for future used. Banana peel is used widely because of its nutritional values and its healthy. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms and can be apply in coatings or dental applications. The varieties of ripening of banana peel effects the mechanical, physical and chemical properties of its peel. Several methods are proposed for powder size of cellulose preparation include, hammer mill, grinding and ball milling method. A modification needed for the uniform dispersability of the cellulose powder in polymer matrix which the method will modify the hydrophobicity ...

Replacement of diesel fuel with emulsion fuel is one way to overcome exhaust emissions from combustion, especially smoke emissions and increases combustion efficiency. This study used an emulsion with a mixture of 35% water and 65% diesel. The study used a Diamond DI 800 diesel engine by varying injection times by 13°BTDC - 19°BTDC intervals of 2°BTDC with loads of 1000 W (low load), 2500W (med load), and 4000 W (high load). The engine rotation was kept constant 1500 rpm. The results showed that despite a decrease in exhaust emissions and an increase in combustion efficiency, the value of thermal efficiency increased to 55.3% compared to standard diesel fuel at 17°BTDC. Smoke emissions decreased by 2.53%. it was accompanied by an increase in fuel consumption, under standard conditions fuel consumption increased by 15%, but by advancing injection time, fuel consumption decreased to 5,47%, low engine torque and power decreased by 3.17% with max output 3,056 HP.Replacement of diesel fuel with emulsion fuel is one way to overcome exhaust emissions from combustion, especially smoke emissions and increases combustion efficiency. This study used an emulsion with a mixture of 35% water and 65% diesel. The study used a Diamond DI 800 diesel engine by varying injection times by 13°BTDC - 19°BTDC intervals of 2°BTDC with loads of 1000 W (low load), 2500W (med load), and 4000 W (high load). The engine rotation was kept constant 1500 rpm. The results showed that despite a decrease in exhaust emissions and an increase in combustion efficiency, the value of thermal efficiency increased to 55.3% compared to standard diesel fuel at 17°BTDC. Smoke emissions decreased by 2.53%. it was accompanied by an increase in fuel consumption, under standard conditions fuel consumption increased by 15%, but by advancing injection time, fuel consumption decreased to 5,47%, low engine torque and power decreased by 3.17% with max output 3,056 HP.

Biodegradable plastic or bioplastic as eco-friendly polymers are used for replacement of commercial plastics in the market due to its biodegradability and non-pollutant properties. Bioplastics give many advantages for food packaging and medical purposes. Bioplastics can be manufactured from natural fiber as the main source. One of the main potentials of natural fibers in Indonesia is rice straw. The aims of this research were to manufacture bioplastics and to study their physical and mechanical characteristics. Bioplastics were made by mixing rice straw pulp as main cellulose source with plasticizer and chitosan as additives. Glycerol as a plasticizer was added with the variation of glycerol concentrations of 25%, 30%, and 35%. The test done on the bioplastics were molecular structure analysis using Fourier-transform Infrared Spectroscopy (FTIR), water swelling test, oil swelling test, tensile strength test using Universal Testing Machine, and soil-based biodegradation test. Results showed that best bioplastics (bioplastic with 35% glycerol) in this study contains functional groups of N-H (3393.9 cm−1), O-H (3391cm−1), C-H (2938.68 cm−1), C-O (1111.05 cm−1), C-N (1230.64 cm−1). It resulted 86.866% in water swelling test, 29.109% in oil swelling test, 6 MPa in tensile strength test, and it broke at 65% elongation. During biodegradation test for 15 days under dry soil and wet soil, the weight of the bioplastic reduced 18.496% and 21.317%, respectively.

Most batik industries dispose of wastewater into the environment without being processed first. Biological wastewater treatment effectively can reduce color parameters. Optimization was carried out to determine the optimum condition of growth. The aim of this study were to obtain the optimum concentration of inoculum, pH, incubation time and culture condition in the decolorization of Indigosol blue batik wastewater by Aspergillus sp. 3 strain G-LnsP isolate. The isolate was isolated from batik wastewater. Variations of inoculum concentration were 100, 150, 200, 250 spores / ml, pH was 3, 4, 5, 6, 7, 8, the incubation time was 24, 48 and 72 hours, and the culture conditions were agitated. The parameters observed in the optimization were the percentage of decolorization analyzed by the spectrophotometer method. The optimization results showed that the best inoculum concentration was 100 spores / ml with decolorization 94.8%. The optimum pH was 3 with decolorization of 96.6%. The optimum incubation time was 24 hours with decolorization degradation 95.32%. Decolorization of culture conditions were found to be higher in agitated conditions than static conditions

In the last decade, the concern of fossil-based oil or petroleum crisis has driven the acceleration of biorefinery application. This method refers to the utilization of biomass as substituent for petroleum to meet the community needs. One of prospective biorefinery products is levulinic acid. Sugarcane bagasses (SCB) has attracted a lot of attention as a biomass source for producing levulinic acid. In this study, levulinic acid (LA) was synthesized from Indonesian sugarcane bagasse (SCB) using two-step acid catalyzed treatment method, optimizing product yield. These experiments were conducted in a batch stirred reactor with stirring rate of 50 rpm for 30 min. The effect of HCl concentration (0.5 and 1.0 M) and solid mass-liquid volume ratio (1:10, 1:12.5, 1:15, 1:17.5 and 1:20) at temperature of 160°C were investigated. The highest levulinic yield was 43.42%, obtained at 1.0 M of hydrochloric acid concentration and 1:17.5 of solid mass-liquid volume ratio.