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The agriculture waste material can give benefit to many production industries. The studied crop is corn (Zea Mays)stalk. The objective of this work was to analysis the chemical composition; to study chemical pulping and papermaking properties of corn stalk and; to investigate the fiber morphology of properties of those crops. Firstly, the chemical composition of corn stalk were determined and compared with other non-woods. After that, chemical corn stalk was conducted in this analysis followed the physical and mechanical properties. The result showed that, corn stalk have cellulose (39.0%) and lignin content is the lowest (7.3%) content rather than other composition. In chemical pulping, reached high pulp yields had been produced and the strength properties: tear index, tensile index, burst and fold verified that they were of an acceptable quality for papermaking. This crop morphology was observed by Scanning Electron Microscopic (SEM), which showed a condensed composition of fiber structure. This study can developed a friendly product and promote the green technology, suitable to be used as an alternative pulp in paper making industry.Keywords:Fiber, Corn stalk, Composition, Green technology, Pulp and paper making.

The aim of this study was to study the morphology and structural characteristic of NCC hydrolyzed from filter paper. The NCCs were extracted by acid hydrolysis at 50°C for 1 hour, using 55% conc. H2SO4 under vigorous mechanical stirring, centrifugation at 12000 rpm in distillate water and followed by homogenizing at 7000 rpm. The morphology and surface profiles of the NCC suspension was characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The crystalline structure of the NCC was evaluated by using X-ray diffraction (XRD) technique. As a result, hydrolysed NCC was found to have a rod liked shape with diameter in the range of 100-300nm length and 10-50nm width, with the aspect ratio value of 10.3 nm. According to XRD investigations, the semi-crystalline cellulose was observed with the presence of an amorphous broad hump and crystalline peaks at 2θ of 15o and 22.7o, respectively. The crystalinity index of the raw filter paper was calculated as 86.7 % and increased to 94.4 % as it was extracted to NCC. Crystallite size of raw filter paper and NCC was calculated as 20.6 nm and 11.4 nm, respectively

Environmental awareness and depletion of the wood resources are among vital factors that motivate various researchers to explore the potential of agro-based crops as an alternative source of fiber material in paper industries such as writing, printing, wrapping, and packaging. Fibers from agro-based crops are available in abundance, low cost, and most importantly its biodegradability features, which sometimes referred as “ecofriendly” materials. This paper reports the biopulping of pineapple leaf fiber (PALF) by Ceriporiopsis subvermispora towards the properties of its fiber and paper forms. The individual fibers were characterized having good tensile properties at 0.3% of fungus treatment and favourable structural properties as characterized by Fourier transform infra-red (FTIR) spectroscopy. It was also shown that the PALF paper achieved desirable tear index value and uniform morphological observations compared to the conventional chemical pulping method. This new approach of pulping PALF finds applications in paper and packaging products which requires biofriendly characteristic and cost effective.

Rabbit is a traditional textile material and has protein content about 93%. Rabbit hair wastes are abundantly present in textile processing due to its poor spinnability. In order to recycle the waste rabbit fiber effectively, the rabbit protein was researched. The papermaking method was performed for the first time and their properties of the hybrid paper were discussed in this study. Different contents of rabbit protein were successfully prepared and mixed with pulp fibers to remade papers. Finally, performances of these papers were characterized. The results showed that the surface of the rabbit protein paper was flat, white and writing fluently. The ink absorbance of novel paper increased. Moreover mechanical properties of the rabbit protein paper were stronger than the untreated paper. The folding endurance decreased firstly and then increased.

Both water repellency and water vapour barrier properties were endowed at paper surface by coating with beeswax-chitosan latex. It was found that the water vapour transmission rate of coated paper decreased as the drying temperature increased. However, water contact angle was not affected with it. Although the surface morphology deformed at high drying temperature, the roughness values maintained at micro-scale. Further analysis indicated that the water vapour barrier property of coated paper was influenced by the density of the coating layer.

The study aimed to describe the alkaline treatment advantage to remove ash component from natural rice straws. Most of the ash component in the rice straw is silica. High ash content is particularly harmful to cutting tools and to chemical to recovery systems in the pulp paper industry. In this study, the silica content has been removed simply through by immersion process in the 5% sodium hydroxide solution to obtain de-silicated rice straw. The study revealed the effectiveness of this alkaline process and the compatibility in commercial practice. The rice straw pulping is considered competitively to complement the global demand of raw material in paper production. Therefore, the treated rice straw plays an important role in providing raw material in the form of wood and rice straw blend feedstock for pulp and paper industry.

Based on the analysis of the concept of green technology innovation capability, this paper not only structures the evaluation index system of green technology innovation capability in pulp and paper enterprises, builds the evaluation model of green technology innovation capability for pulp and paper enterprises based on Support Vector Machines with Radial Basis Function kernel, but also achieves the optimization of kernel function parameters, penalty factors and insensitive parameters based on a heuristic algorithm for tuning hyper-parameters. This model is more suitable for pulp and paper enterprises to evaluate green technology innovation capability, compared with the evaluation method of BP neural network.

The wettability of the carbon composite electrode on paper substrate was studied using contact angle measurement. Y-Shield HSF54 carbon composite material were coated on paper substrates with a mask using squeegee coating technique. Contact angles of the ten polar probe liquids with the HSF54 electrodes were measured using a customed-built image acquisition system. With the contact angles obtained for each probe liquid placed on the electrodes, the surface tension of the electrodes was determined using Fox-Zisman theory. The result showed that the critical surface tension of HSF54 carbon composite electrodes was 37.2 mN/m which is considered to be moderately hydrophobic.

Relaxation function can well reflect the microscopic polarization mechanism of dielectric. In order to analyze the influence of moisture and temperature on relaxation function of oil-paper insulation, building a physical model of the oil-paper insulation system containing moisture and obtaining the expression of relaxation function. Setting up a testing device for the oil paper insulation dielectric spectroscopy in the laboratory, the parameter values of relaxation function expression were obtained according to test result by Fourier inverse transformation. The results show that the relaxation function containing three relaxation factors are more suited for the relaxation of oil-paper insulation containing moisture content and microscopic polarization mechanism, moisture and temperature have a significant effect on relaxation function.

In this paper, a kind of fibrous TiO2 has been prepared through hydrothermal synthesis and a paper fabricated from the fibrous TiO2 has been obtained. The composition, morphology, and size of the fibrous TiO2 were characterized by using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. And the morphology of the paper was characterized by polarizing microscope. The thickness, softness, and writing properties of the paper were detected by a vernier caliper and a pen. The results indicate that the diameter of the fibrous TiO2 is ~ 200 nm, the thickness of the fabricated paper is ~ 0.35 mm, and the paper can be tolerated writing by a UM-100 ball pen. The excellent properties of the prepared paper may change the applications of fibrous TiO2 in papermaking industry.

By applying sodium hydroxide/urea and a sample freeze drying method, we successfully synthesized green cellulose aerogel from paper waste for the first time. We adjusted the cellulose concentration from 1.5 percents to 4 percents in the initial hydrogel. They yielded densities changing from 0.03-0.1 g/cm3.The absorption capacities varied from 9 to 20 times of their own weight. To investigate the water absorption capacity in relationship with the initial chemical dosage, we changed the input amount of urea and sodium hydroxide, which is the first study ever. The thermal conductivity of the 2 percents sample ranged from 0.029-0.032 W/mK. Besides, the material has a high potential to be used in diaper industry as it is biodegradable which is better than most super absorbent polymers.

Fluorocarbons were added into the mixture of modified starch and sodium alginate to get uniform coating solution, and the solution was then coated on the surface of transparent paper. The color as well as grease barrier property of paper at different coating weight were studied. The results showed that color under different coating weights were not significantly different from base paper. The scanning electron microscopy (SEM) diagram showed the surface of paper became smoother and more homogeneous as the coating weight increased. The grease barrier property of coated papers were significantly improved compared with base paper according to Tappi-559 kit test. A highest grease rating number of 12 was obtained when the coating weight became 3.3 g/m2. The dynamic changes in contact angle studies revealed that the contact angle of the base paper was continuously decreased from 29.41 °minutes to 23.46 °within 20, the contact angles of coated papers were significantly increased, and reaching a steady state within 2min with the maximum rate of contact angle change was of merely 0.06 ° / min.

The use of agricultural wastes and natural materials in new technologies is a novel subject. Consequently, an attempt has been made to formulate a synthetic fluid using an organic water, Water Extract from Fermented Ground Maize (WEFGM) and compare its performance with water-based sample in turning operation using a mild steel as workpiece. Two samples of synthetic fluids were formulated from each of deionized WEFGM, ordinary WEFGM and deionized water as base-fluids at two composition (5 and 10%vol) levels of selected additives. The results of experimental analysis of heat transfer properties of these synthetic fluids exist, hence the need to ascertain the actual performance output. Temperature-Time Gradient (TTG) which is a rate of temperature drop (heat withdrawn) from the work zone was used as evaluation parameters. The result showed that deionized WEFGM is the most efficient of the entire samples at both compositions with an average TTG of 3.61 and 2.16 °C/min at 10 and 5% additive concentration respectively. At lower additive concentration which is more economically advantageous, the performance rating is deionized WEFGM>>WEFGM>>deionized Water. This implies that WEFGM is more effective than water as a base fluid for synthetic fluid in performance as it has been previously so reported in properties. Meanwhile, T-test statistical analysis (using IBM SPSS 23) shows that there is highly significant difference in TTG at each time of application of individual fluid (p0.05) implying that the fluids can all work as coolants and relatively have comparable performance output.

When processing in the manufacture for production of paperboard boxes, there arises amount of waste paper as material, which is subsequently sent for recycling. The paper passes through the first crushing device, which ensures small pieces so that they can be transported by pipeline to a pressing apparatus. Paper material in the molding machine is forced into the pits of suitable size due to the additional handling and transport. So both pipe as well as the molding machine may be so congested with material during the failure that the equipment requires unexpected additional cleaning. The sensor detects the level of waste material in pressing device, thereby avoiding congestion in a timely manner and prevents subsequent failure. The sensor uses the resonant frequency of the oscillating rod. The microprocessor controls and evaluates the response of the rod oscillations. Sensor performance was exposed to qualification tests when it shows ability to operate also in extreme conditions such as dirty and dusty surrounding with high humidity and temperature level. Sensor detects the vibration attenuation at the poles of the rod that is caused by touching different materials. Thus may indicate changing concentration level of a material and not just pieces of paper but for example, also sand or other suitable materials or height of fluid surface.

Proper waste management in Malaysia is needed for the organic wastes such as pineapple leaf and cassava peel where affects the increase the amount of solid waste dump into landfill. Thus, to overcome this problem agro waste material can be constructed in many production industries to commercialize the use of alternative fibre for the paper industry. The main objective of this study is to demonstrate the use of fibrous in pineapple leaf and cassava peel by production of alternative fibre based on chemical properties and surface morphology characteristic. This study conducted for the chemical composition by analysed by TAPPI Test method, Chlorination method and Kuchner-Hoffner method. Every chemical components analyse; Cellulose (Kuchner-Hoofner), Holocellulose (Chlorination method), Hemicellulose (Chlorination method), Hemicellulose, Ash content (T211-om-93), Lignin content (T222-om-98) and Sodium Hydroxide soluble (T203-om-88). The scanning electron microscopy (SEM) was used to observe and determine the morphological characteristic of both crops. The result indicates that pineapple leaf more suitable for becoming an alternative fibre than cassava peels. Pineapple leaves have a high Holocellulose content (85.7%), cassava peels 66%, followed by Cellulose pineapple leaf (66.2%), cassava peels (37.9%). However, hemicellulose content in pineapple leaf (19.5%) less than cassava peels (37.0%). Lignin content of pineapple leaf is lower (4.2%) compared to cassava peels (7.52%) in this study. From SEM images, cassava peel contained abundance fibre such as hemicellulose and cellulose that is held by the lignin in it and Pineapple leaves give a condensed composition of fibre structure. The chemical compositions and morphology study of pineapple leaf and cassava indicate pineapple leaf have a high percentage to be used as an alternative pulp in paper making industry, promoting the green technology. However, cassava peels make some of properties that can also be through for the paper industry.

Nowadays, over 95 % of fly ash is used as construction products in the Czech Republic. However, around 80 % of fly ash is used for renovation of open-pit quarries and areas affected by human activity. Production of artificial aggregate is the way to use over 90 % of energy by-products in the building material industry. It is necessary to find appropriate combination of parameters of input materials and conditions of production to get optimal properties of aggregate. The paper gives an account of the influence of parameters of fly ash and conditions of firing on the quality of ceramic body made from fly ash. Temperatures of 1050 °C, 1150 °C and 1200 °C were examined. The research focused on the structure of the ceramic body as well as its physico-mechanical parameters.

Both qualitative and quantitative effect of TiO2 suspension presence in cigarette filter have been analyzed in order to reduce harmful substances in cigarette smoke, optimizing the capability of TiO2 suspension as nano filter in cigarette filters and reviewing the analysis in order to obtain results with the best variation. Samples in the form of filter paper that has passed of the smoke with some variation treatment as it become ready to be tested and analyzed. Parameter such as concentration and volume variation of TiO2 suspension, and also the inputting method of TiO2 suspension into cigarette filter. Samples were characterized using FT-IR spectrophotometer and samples data absorbance obtained in each catchment area. The results showed that by reducing absorbance value percentage of each catchment area, with inputting method of TiO2 suspension through the cigarette filter tip and base, it appears that the most stable and lowest reduction present in C3 and H3, which is sample with 1.85 mol/liter concentration and 0.3 ml suspension volume. Both sample reduced particulate matters significantly after confirmed with X-Ray Fluorescence and SEM-EDS results, and was compared to sample filter without TiO2. Inputting method of TiO2 suspension through a base of cigarette butt is better and safer than through end of cigarette filter.

The manufacturing of furniture using rattan is becoming common nowadays, and creates high amount of waste that can be value-added into binderless particleboards (BPB). In order to determine the suitability of the rattan waste for production of BPB, characterization of rattan waste is executed and reported in this paper. The physical properties such as density and moisture content of the rattan waste, together with its morphological study and thermal analysis as well as lignin content are evaluated. It is observed that density and moisture content for rattan waste are in the range of 0.64g/cm3, and 11.3% respectively. On the other hand, the morphology of rattan stem showed that rattan waste has various diameters of vascular bundles along with wide metaxylem vessels as well as thin-walled fibres. Thermal analysis of rattan waste explicated that rattan waste went through endothermic process with peak melting point of 177.80 °C during heating. The greatest weight loss occurred at 257.03 °C. Rattan waste has high lignin content of 21.2% that obtained through Klason lignin test. These promising preliminary results show that the rattan waste is appropriate to be used as raw materials in producing BPB.

Graphene is a remarkable material with high electron mobility, good mechanical strength and almost transparent. In this paper, we review the available methods which are chemical vapour deposition, Hummers and electrochemical exfoliation method for the production of graphene. Among the extensive studies in the application of graphene, supercapacitor has gained much attention nowadays. Therefore, we also briefly review the application of graphene as electrodes for the supercapacitor devices.

Dry rot fungus (Serpula lacrymans) is wood-decaying fungus. It grows frequently in our territory and it causes big damages on structures. Remediation of damaged structures is very difficult, sometimes impossible, therefore it is necessary to study preventive protection against dry rot fungus. PVA nanofibred fabrics with synthetic and natural biocidal additives were used for this experiment. Filter papers soaked in dopes with biocidal substances were other materials used for this experiment. Pieces of nanofiber fabrics and pieces of filter papers soaked in dopes were placed to Petri dishes with broth. Small cuts of dry rot fungus were placed around them. This experiment was performed in conditions, which promote the growth of dry rot fungus. Growth of dry rot fungus was studied.

This paper describes the method of treating wheat straw pulp black liquor with microwave radiation. The granular activated carbon and CuO are used as a catalyst.Effects of effective factors such as the total amount, ratio, microwave power, time on treating process are studied. The reaction mechanism is also researched. The results indicate that the oxidative decomposition process of lignin or organic pollutants is combined action of activated carbon and CuO absorption-degradation with microwave induced oxidization. This approach is easy to operate, quickly to treat, completely to react and no new pollutants. So it is used to treat black liquor of containing organic pollutes which is hardly degraded.

In order to optimize the regeneration conditions of cation exchange resin, the paper based on the actual data of production, the cation exchange resin regeneration condition was optimized by the process of mathematical modeling, which achieved good results. Research showed that reducing regeneration acid feeding time could effectively reduce the consumption. It could reduce the production cost and make enterprises obtain more economic benefits. Calculated and measured were agreed showed that the study and calculation on regeneration of cation bed were accord with actual production, and had practical value for ion regeneration process. Through least square fitting showed that the 80min was the best acid feeding time, acid consumption of unit volume of water was the lowest.

This paper aims to study the effect of using Oxidized White Liquor (OWL) on pulp brightness in peroxide bleaching. The proper setting of the concentration of hydrogen peroxide, the bleaching temperature, and the bleaching time was also studied. The Central Composite Design (CCD) was proposed to generate necessary experimental runs. Regression analysis was used to determine the relationship equation. Optimization helped determine that to obtain the targeted brightness of 83%, the ratio between the volume of OWL and sodium hydroxide should be 50:50. This ratio should be used with a concentration of hydrogen peroxide at 6.9 g/kg, a bleaching temperature of 90 oC and a bleaching time of 75 minutes.

Oil Palm Empty Fruit Bunch (OPEFB) contributes more than 50% of oil palm biomass wastes in Malaysia. This provides tremendous opportunities for value-added product generation from recycling and utilizing its latent capacity. In this work, the performance of physically-pretreated OPEFB fibers without any chemical treatment for Pb2+ removal from aqueous system was evaluated. Three different size ranges (1-5 cm, 0.5-2 mm and 0.005-0.02 mm) of raw sorbent, pH (4-10) and contact time (2-150 min) for Pb2+ batch adsorption were tested. The kinetic data were evaluated by the pseudo-first-order, pseudo-second-order and intra-particle diffusion model. The experimental data were well described by the pseudo-second-order model with r2=0.997. Adsorption efficiency was size-dependent with about 38% sorption increase at 0.005-0.02 mm, and reached 94% efficiency, achieved 47.49 mg/g capacity with 500 ppm Pb2+ at pH 7.5, in 60 min. The eco-friendly, low cost sorbent can be applied as green, effective adsorbent in waste water remediation.

The effect of heat on the quality of spray dried Tongkat Ali extract was investigated at three different air inlet temperatures (100°C, 180°C and 2200C). Response surface methodology employing the Box-Behnken Design was employed to hunt for the optimum operating conditions at these temperatures. Good retentions of eurycomanone, total polysaccharides and glycosaponins were exhibited during the spray drying process. However, protein was found to be susceptible to thermal degradation during the spray drying process. Use of high air inlet temperatures (i.e. 1800C and 2200C) in spray drying led to greater process yield, lower moisture contents, produced non-sticky particles, and resulted in good powder size distribution of Tongkat Ali extract compared to spray drying at 1000C.

Oil contamination has caused more public anxiety than other waste or spilt materials into the marine environment. Oil sorbents of high sorption capacity, biodegradable, readily available and low cost, are important for protection of water environment, especially from oil spillage. This work deals with raw and modified corn silk, an agricultural waste, as a low cost sorbent for oil-products spill cleanup in the aquatic environment. Corn silk was modified using fatty acid (oleic acid) to improve its sorption capacity. The chemical functional groups of raw and modified corn silk were analyzed by Fourier transform infrared (FTIR) spectroscopy. Kinetic tests were conducted with a series of contact times. The kinetic studies showed good correlation coefficients for a pseudo-second-order kinetic model. The oleic acid treated corn silk (OTCS) showed high degree of hydrophobicity and oil sorption capacity of approximately 10.7 and 11.90 g oil/g sorbent for Tapis and Arabian crude oil, respectively. Corn silk is a cheap waste material that can be treated to have an acceptable sorption capacity which can be used as an alternative to the commercial synthetic sorbents such as polypropylene.

Wastewater originated from domestic or industry use need to be treated before discharge it to the environment. Particle size is one of the parameter that determine efficient operation of wastewater treatment plant. The present work conducts a comparative study of non-imaging and imaging based particle size analysis tools to analyze the limitations and advantages of using such equipment. The study utilizes particle size analyzer (PSA) as non-imaging tool and light microscope as imaging tool to determine particle sizes in various waste water samples. For this analysis domestic wastewater influent and effluent are analyzed with both techniques. In addition, palm oil mill effluent (POME) has also been analyzed after Fenton process to compare the particle size using these tools. PSA shows most of the particles in the influent and effluent are in the size range of 100 to 700 μm, while microscopy shows additional information of aggregates structure in POME sample showing promising possibility of identifying complex structure of aggregates present in the sample.

This study aimed to analyze the kinetics of enzymatic hydrolysis of cellulose. Cellulase enzyme was obtained fromAspergillusnigergrown on filter paper and the hydrolysis process was carried out in solid state. The kinetic reviewed here was the relationship between glucose production and cellulose mass reduction to optimize the parameters of Monod equation at various moisture levels.

The construction industry is responsible for high energy and raw materials consumption. Thus, it is important to minimize the high energy consumption by taking advantage of renewable energy sources and reusing industrial waste, decreasing the extraction of natural materials. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. The simultaneous incorporation of PCM and fly ash (FA) can reduce the energetic consumption and the amount of materials landfilled. However, the addition of these materials in mortars modifies its characteristics. The main purpose of this study was the production and characterization in the fresh and hardened state of mortars with incorporation of different contents of PCM and FA. The binders studied were aerial lime, hydraulic lime, gypsum and cement. The proportion of PCM studied was 0%, 20%, 40% and 60% of the mass of the sand. The content of fly ash added to the mortars was 0%, 20%, 40% and 60% of the mass of the binder. It was possible to observe that the incorporation of PCM and fly ash in mortars caused differences in properties such as workability, microstructure, water absorption, compressive strength, flexural strength and adhesion.

The purpose of the present study was to investigate the ability ofMicrobacterium liquefaciensstrain MNSH2-PHGII-2, isolated from a Mexican silver mine, for removing Ni and V from spent catalyst at 80% (w/v) pulp density in a glass-column system at laboratory conditions. Firstly, microbial culture was adapted to spent catalyst at 0.1% (w/v) in liquid culture then, it was assayed by its ability to remove Ni and V from a spent catalyst in a glass-column system. Spent catalyst was packed at 80% (w/v) pulp density and inoculated at 20% (3x108CFU/ml); air was supplied at 80 ml/min and then incubated at 30°C during 14 days. Parameters such as microbial growth, pH, Ni and V residual concentrations, in catalyst, were determined at days 7 and 14. The result showed thatMicrobacterium liquefaciensstrain MNSH2-PHGII-2 in the glass-column system was able to remove 1007.4 mg/kg of Ni while V was removed at an extent of 5360.5 mg/kg. Microbial removal for other metals in catalyst was non-significant, that indicated the specificity ofMicrobacterium liquefaciensto remove Ni and V.

Ashes from lignite combustion for power generation contain strategic metals, metalloids and rare earth elements and may thus be a potential source of industrially demanded metals. The presented project focuses on the assessment and exploitation of this potential raw material. Lignite ash assessment showed that largest ash amounts for potential exploitation are available in the Lusatia district, Saxony. Mechanical ash pre-treatment in principle provided enriched fractions by different methods but still suffered from low yields of enriched fractions. Thermal ash processing showed multiple significant phase changes compared to original ash. Subsequent chemical leaching using HClaq resulted in high metal extraction. Alternatively, bioleaching was applied using acidophilic Fe (II) and S-oxidizing or Fe (III)-reducing microorganisms (MO) as well as heterotrophic MO. The results indicated likewise high and partly specific metal mobilizations. Industrial ash exploitation was accomplished by direct reaction with acids resulting in Al-Fe-solutions which potentially can be applied in water treatment.

This study focuses on the biodesulfurization of lignite specifically the reduction of organic sulfur, namely aliphatic mercaptans/thiolsviabioprocess methods. The process was conducted by using multistage artificial biotreatment (A-Bmt) andPseudoclavibactersp.SKC/XLW-1 strains as biocatalysts. The aims are to improve the recovery of clean coal by reducing the organic sulfur both in nodules and globular forms on the maceral surface during the stage of coal biooxidation prior to column bioflotation stage, in which it is still possible to achieve higher recovery of fine coal grains without sulphide mineral. The results shows that the A-Bmt method carried out through biooxidation stage followed by column bioflotation stage has better performance compared to the method without biooxidation stage. The results of this study show that the content of organic sulfur are lower by 25%.

Peru is mining country with a great diversity of mineral resource. The high grade ores are declining, and there is a need to implement new techniques for recycling metals (Cu, Au, Zn, Pb, etc) from low-grade ores. In order to answer this question, the bioleaching of copper from sulphide ore (FeS2 45.30%, CuFeS2 1.90%, ZnS 8.90%, FeAsS 13.12%, PbS 3.69%) was evaluated with different concentrations of Fe2+ using an iron-oxidizing native microbial consortium.The samples were collected from drainage acid mine (4100 m.a.s.l.) located in the south of Huancavelica region and the sample of ore from middle Huaraz region (3200 m.a.s.l.). Microorganisms were isolated in 9k medium at pH 1.8, 22oC. Bioleaching test were performed in two consecutive steps to 150 rpm at 22oC, monitoring pH, ORP (mV). Assays varying the concentration of Fe2+ (0 mM – 53 mM) were performed with a pulp density of 1% and 2% at each step, and with an inoculum 10% (v/v) to a microbial concentration of 108 cel/mL.We isolated a microbial consortium after 8 weeks with presence of bacteria Acidithiobacillus ferrooxidans-like. In assays, copper was solubilized. The microbial concentration in the tests was (2x107- 4x107cel/mL). In the first stage, the test with 21 mM Fe2+ recovered 62% copper. In the next step, with the bacterial concentration of the first step, bioleaching time is reduced by 22% for copper recovery (63%) in absence of Fe2+.With these data, we observed that the addition of iron is not necessary in a stage adaptation when the mineral contain iron.

Groundwater contamination due to mining, industrial and agricultural activities is a source of concern, especially with the advent of more stringent environmental legislation. Water sources in South Africa are multi-functional as the same water used in industrial processes is also used in agriculture.[1] Mining activities in the Northern Cape of South Africa, is largely as a result of manganese mining where Mn (II) and Fe (II) is removed. The treatment of the effluent discharged to the environment is therefore seen as a priority.Biosorption has proven to be a viable alternative to the use of conventional heavy metal removal methods. [2, 3] The re-usability of the biomaterial was investigated using a batch system. The biomaterial was contacted with Mn (II) sulfate, after which the supernatant was analysed for metal content. The biosorbent was then dried and desorbed using HCl. This process was repeated 3 times to investigate whether the biomaterial deteriorated and whether the biosorption process was affected by multiple use of the same biomaterial. The results showed that the biosorption capacity reduced with each successive use of the biomaterial.

For petroleum industries, CO2 can cause corrosion, and heating-value reduction. However, CO2 can be used to enhance the oil recovery for oil production. However, the amount of CO2 supply is not enough because the cost of carbon capture is high. The main sources of CO2 come from power generation. The technology to capture CO2 is carbon capture and storage or CCS. Currently, the effective technology to remove CO2 from the power plants is chemical absorption and chemicals used in this technology play a key role. Nowadays, the commercially used solvents are monoethanolamine (MEA). Nevertheless, it also has disadvantages such as low capacity and high energy requirement for regeneration thus making CCS costly. Therefore, many new solvents such as 2-(methylamino) ethanol or 2-MAE have been developed to improve efficiency and to reduce the cost of CO2 capture. Therefore, the objective of this work is to measure the solubility data of CO2 in a 5M aqueous solution of 2-MAE as a promising solvent at the temperature from 30 °C to 80 °C and CO2 partial pressures ranging from 5 to 100 kPa. The solubility results of CO2 in 2-MAE solution are compared with those of aqueous solution of MEA. In term of cyclic capacities, the results show that 2-MAE provides higher performance which is up to 86.8% and 150.9% higher than that of MEA at 15 and 100 kPa, respectively. Furthermore, the results present that the CO2 loading can increase as partial pressure increases and decrease at higher temperature. It can be concluded that an increase in cyclic capacity leads to the decrease in energy requirement for solution regeneration and liquid-circulation rate, leading to the reduction of the overall capital and operating costs and resulting in the decrease in cost of carbon capture.

The biopolymer material, lignin, was recovered from the black liquor by acidification of the black liquor using sulfuric acid. Several purification techniques were carried out to produce the high purity of lignin such as gradual precipitation of lignin from black liquor (first stage: precipitation at pH 7, second stage: precipitation at pH 2) and the diluting of crude lignin by sodium hydroxide then followed by re-precipitation at different temperature. Subsequently, the impurities of lignin product resulted from each purification techniques was determined as ash content that analyzed using temperature program furnace; and the content of lignin was investigated using spectrophotometer UV-Vis. The result showed that the content of lignin of material produced from gradual precipitation was approximately 77.6%. It was higher than the content of lignin about 3.4% of material produced from direct precipitation to pH 2. In addition, the elevating of temperature from 40 to 60°C was no considerably affect to the content of lignin in precipitate produced from re-precipitation of crude lignin solution in sodium hydroxide. Nonetheless, the content of lignin of precipitate improved 15% when the temperature of re-precipitation of crude lignin solution in sodium hydroxide was raised from room temperature to 40-60°C.

The application of photodegradable polyethylene is increasingly important for agricultural uses due to its ability to degrade after suggested shelf life and to counter measure pollution issue caused by conventional polyethylene films. The photodegradable polyethylene (PE) mixtures were formulated with added polypropylene (PP) and photodegradant (RM master batch) and tested in oil palm seedlings cultivation. PP is known to have photodegradable ability and RM master batch is proven to induce photo degradation of polyethylene. Thus, the mixture of these three components according to different ratios was processed into agricultural plastic films. There are four formulations that are tested in this study, namely T1 (80% PE:20% PP:5% RM master batch), T2 (70% PE:30% PP:5% RM master batch), T3 (80% PE:20% PP:3% RM master batch) and T4 (70% PE:30% PP:3% RM master batch). All formulations except control sample were added with photodegradant to impart degradation reaction and compatibiliser was also affixed to allow coalesce between polyethylene and polypropylene. Carbon black was added 0.5% into the formulation as for poly bags application, dark environment of soil is crucial for root development and growth. Penetration of sun light into the planting soil could commence development of shoot instead of root growth. All four formulations showed observable morphological changes on microscopic images on the surfaces after being used in oil palm nursery. From the study, it is shown that T1 and T3, with 20% of additional polypropylene had demonstrated clear surface disintegration when viewed microscopically. The addition of 3% and 5% of photodegradant into the formulations did not show any expressive difference thus suggesting that 3% of photodegradant is the optimum amount to induce photo degradation.

The objective of this study is to investigate the ability of Elaeis guineensis fruit fiber or known as oil palm mesocarp fiber (OPMF) to adsorb nickel from aqueous solution. As one of the major oil palm producer, Malaysia has abundantly oil palm waste that potentially be used as biosorbent. Limited studies used OPMF as biosorbent to remove nickel, thus it was used in this study. The effects of pH, initial metal concentration and contact time on nickel uptake were studied. The OPMF was soaked in nickel nitrate aqueous solution and the Ni-loaded OPMF being digested to analyse the nickel concentration by using ICP-OES. The adsorption was investigated in the pH range of 2.0-8.0 and the optimum pH for nickel removal was found to be 7.0. The contact time was varied between 5 to 120 mins and the nickel adsorption was found to achieve equilibrium in a very short time (i.e. R2 of 0.98. The kinetic studies showed that the pseudo-second order model is the best model with the correlation coefficients of > 0.99 for all concentrations. Overall, the adsorption of nickel by OPMF gave positive results and the used of OPMF as biosorbent has great potential to be applied in the future.

In this study, d-limonene as green solvent was used as an alternative to n-hexane to recover the residual crude palm oil (RCPO) from the OPDC. The OPDC obtained from the palm oil mill contained about 12.55±3.15% (dry basis) of RCPO. Similar as n-hexane, the results proved that d-limonene as solvent was able to recover 100% of the RCPO from the OPDC successfully. The recyclable of d-limonene was 90%, higher than n-hexane (70%) and not much variation on fatty acids composition of extracted RCPO were observed. To ensure complete RCPO recovery, microscopic observation and FTIR spectra analysis on OPDC before and after the extraction were performed. This study concludes that d-limonene is comparable to n-hexane. However, the residual oil is classified as non-edible as it is not extracted via mechanical method. Therefore, further analysis is necessary in order to determine the potential use of the residual oils in other industries such as pharmaceutical, food packaging, fiberboard manufacturing and others.

The microalgae Chlorella sp. grows well in POME medium sparged with a mixture of carbon dioxide (CO2) gas and air under 10,000 lx of lighting. The percentage of CO2 in the mixture, and the flow rate of the mixture (representing agitation) have important effects on the microalgae biomass yield. However, the percentage recovery of CO2 as microalgae biomass was very low in all cases, indicating that most of the sparged CO2 did not dissolve in the POME and was not sequestered by the microalgae but has in fact escaped with the bubbles into the head-space and out into the atmosphere. This result indicates that in order to increase the percentage of CO2 recovered, the area of improvement is mainly in the mass transfer of CO2 from the gas phase into the liquid phase. To ensure that dissolved CO2 does not re-form bubbles, the mass transfer has to be demand-driven, where the rate of uptake of dissolved CO2 by the microalgae has to be higher than the rate of mass transfer of CO2 from gas phase into the liquid medium.

Graphene oxide (GO) reduction is a promising way for graphene large scale synthesis. Pre-exfoliated graphite was oxidized and reduced. The material was compared to commercial graphene oxide and its reduced sample. The reduction process of graphene oxide is accomplished using sodium borohydride (NaBH4) with variable-valence metal ion – cobalt – assistance. The reduced graphene oxide (RGO) was characterized by Raman spectroscopy. The particle size and suspension stability were determined. Electrical conductivity measurements of GO and RGO samples have been done in temperature range from-150°C to 85°C. Pre-exfoliation effect was determined.

A reduced graphene oxide/nickel (rGO/Ni) composite has been succesfully synthesized using a combination of Marcano’s method for synthesizing graphene oxide (GO), subsequently followed by a facile microwave assisted reduction method. X-ray diffraction results show the presence of graphene and nickel on the prepared samples. In addition, the Fourier Tansform Infrared Spectroscopy measurement showed that the absorption peaks of O-H, C=O, C-OH, and C-O only appear in the GO sample. A Scanning Electron Microscope photograph shows that the morphology of the rGO samples contain nano-layered forms. A Raman spectroscopy characterization of the prepared rGO samples show a peak of G band’s wave number at 1586.5 cm-1. From the calculation of the G band’s wave number, the average number of graphene layers is 1.15.

In this study, three different concentration of organic loading rate (OLR) were investigated to examine the effect of the change in the organic loading rate on the efficiency of the biogas production. Daily amount of biogas of different type of organic loading rate (OLR), rates of production of biogas, removal efficiencies of chemical oxygen demand (COD), total solid (TS) matter, volatile solids (VS) matter from the slurry were investigated in 30 days retention tyme using 50 L digester. The digester was operated at different organic feeding rates of 25000 mg/L COD, 50000 mg/L COD, and 75000 mg/L COD. The material used in this system is the fruits waste, vegetables waste and cow dung. The system operated in continuous system. The reactor showed stable performance with the highest quality of methane (concentration about70.3% of CH4) and rate of biogas production is 38.1 L/day with COD reduction of 52.1% during organic loading rate 50000 mg/L COD. As the organic loading rate was increased, the COD degradation and biogas yield decreased. Based on this result, the OLR of 50000 mg/L COD is suggested as design criteria for pilot biogas production.

This study aims to directly analyze the production of hydrogen and methane gas from POME via high frequency ultrasonication atomization. The advantage of the currently common process was studied in regards to the application of low frequency ultrasonic pretreatment prior to biological processes; anaerobic digestion and fermentation for the production of methane and hydrogen gases respectively. Existing ultrasonic application is limited to sludge disintegration, reducing chemical oxygen demand (COD) values and total solid, while subsequent biological processes take several days to produce gases. However, in this study, high frequency (2.4 MHz) ultrasonic atomization process was able to produce methane and hydrogen gases directly without any biological process. These gases were detected by using an online gas chromatography. The results from the ultrasonication process show that the production gases are consisted majorly of hydrogen compared to methane. Thus, high frequency ultrasonication process can be considered as an alternative method in rapid production of methane and hydrogen gases.

Hydrogen is one of the most abundant elements in the universe and a clean carrier of energy. However, the existence of hydrogen is in different compound forms, in which a great deal of energy is required to split from the compounds. Gasification of biomass is one of the best methods to produce hydrogen. This study focuses on the production of hydrogen in gasification process by using a throated downdraft gasifier and preheated air as gasifying agent. For the study on the effect of gasifying air temperature on hydrogen concentration in the syngas an electric heater was used to preheat the inlet air up to 500°C. The results of the study showed that increasing the gasifying air temperature from 30°C to 500°C increased the volume concentration of hydrogen by 25.1% in the syngas. The increase in hydrogen was steeper when the inlet air was in the lower range temperature (30 to 265°C) as compared to that of the upper range (265 to 500°C).

Calculated carbon dioxide emission from WPT, using equations derived from the UNFCC report, found that the average amount of CO2 emitted from the decomposition of WPT annually for 2011-2032 is equivalent to 14.19 million tonnes. The amounts of CO2 that can be sequestered from the manufacture of the potential products were also calculated. Assuming 50% of the annual availability of WPT in Malaysia from year 2011-2032 is converted into products such as plywood/flooring, bio-ethanol from OPT sap, timber, animal feed and micro-crystalline cellulose, GHG emissions would be reduced by 8.11%; 1.95%; 21.35% and 20.50% respectively. The conversion of WPT into biofuel such as fuel pellets and bio-ethanol could provide more impactful effect through indirect and direct carbon offsets from the displacement of fossil fuel use. Up to 48.26 percent CO2 reduction may be achieved.

Esterification and trans-esterification reactions are an alternative solution for the production of biodiesel from Crude Palm Oil waste. The two previous studies show that the yield obtained was less than 80%. It is necessary to investigate the optimum condition of trans-esterification operation in biodiesel production from CPO waste. Variables used are temperature, time, ratio of molar triglyceride with methanol, and catalyst concentration. According to preliminary temperature treatment variations, it is determined that optimum temperature is 55°C. Meanwhile, the time treatment variations showed that optimum time is 60 minutes. For the ratio of molar triglyceride with methanol, it is determined that 1:10 is the optimum ratio. And last, for the experiment variations of NaOH concentrations it is discovered that the optimum concentration is 1.25%-b. And to conclude the research, the optimum condition for each variable was used where biodiesel’s yield can reach up to 96.67%.

A new carbon material called graphene has been attracting an increasing research interest owing to its unique electrical and mechanical properties that is useful for the various device applications. The synthesis of graphene from graphene oxide usually involves harmful chemical reducing agents that are toxic and undesirable to human and the environment. By avoiding the use of toxic and environmentally harmful reductants, we report a green approach for the reduction of graphene oxide by using reducing sugars to synthesis graphene. Graphite oxide was synthesized from graphite powder using modified Hummers method. Graphite oxide then further exfoliated to graphene oxide by using ultrasonic irradiation. Graphene then was obtained by the mild reduction of graphene oxide with reducing sugars (glucose, lactose and maltose). The structural study of the as-prepared graphene is characterized by Raman spectroscopy and fourier infra red spectroscopy. Raman and FTIR spectra indicates the partial removal of oxygen functional groups from the surface of GO. Characterizations indicate that graphene oxide is successfully reduced to graphene by sugar.

We measured the resistivity and conductivity behavior of activated carbon and an activated carbon – graphene oxide (GO – AC) hybrid using two point probe method. As graphene oxide is well known as insulator, the effects of different ratio of activated carbon on conductivity of hybrid GO – AC was investigated.

Green composites of Glucose-reduced graphene oxide (GrGO) and manganese (IV) oxide (MnO2) were prepared in a typical chemical synthesis route assisted with ultrasonic irradiation. Conductivity studies conducted via 2-point probe method shows GrGO/MnO2(4:1) possessed electrical conductivity of 30.29 S cm-1with energy band gap of 8.47×10-1eV. The increase of D/G intensity ratio of GrGO with increase MnO2loading indicates more disorder carbon or defects are introduced from the reaction of carbon with MnO4-.