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Geopolymers are synthesized by alkali or acid activation of aluminosilicate materials. This paper critically reviews the synthesis kinetics and formation mechanism of geopolymers. A variety of mechanistic tools such as Environmental Scanning Electron Microscopy (ESEM) and in situ Energy Dispersive X-ray diffractometry (EDXRD), in situ Isothermal Conduction Calorimetry (ICC), in situ Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), 1 H low-field Nuclear Magnetic Resonance (NMR) and Isothermal Conduction Calorimetry (ISC), and others and phenomenological models such as the John–Mehl–Avrami–Kolmogorov (JMAK) model, modified Jandar model, and exponential and Knudson linear dispersion models were used to study the geopolymerization kinetics and many mechanisms were proposed for the synthesis of geopolymers. The mechanistic tools and phenomenological models provided new insights about geopolymerization kinetics and formation mechanisms but each of the techniques used possesses some limitations. These limitations need to be removed and new methods or techniques must be developed to overcome these challenges and get more detailed information about all types of geopolymers. The formation mechanism consists of three to four stages such as dissolution of raw materials, polymerization of silica and alumina, condensation, and reorganization. The Si/Al ratio above the Si/Al ratio of reactants is more suitable and it increases the rate or degree of reaction and produces a higher compressive strength geopolymer. The Na/Al ratio of 1

There is growing concern to determine an alternative adsorbent for remediating landfill leachate effluent with minimal environmental impact and operational cost. In this work, four low cost sustainable biocomposite materials such as limestone, peat, activated carbon and zeolite were employed as an adsorbent media in an adsorption batch study for the removal of ammoniacal nitrogen from landfill leachate. Isotherm adsorption models of Langmuir and Freundlich were utilized to analyze the adsorption data. The Langmuir isotherm model showed the best fit for experimental data with a maximum monolayer adsorption capacity of 26.18 mg/g which is indicated that the ammoniacal nitrogen adsorption took placed on the surface of biocomposite with monolayer formation of the adsorbate at a specific homogeneous site. The adsorption isotherm follows Langmuir’s model (R2 = 0.99) and Freundlich’s model (R2 = 0.98

Larut resap domestik mengandungi kepekatan bahancemar NH3-N dan COD yang sangat tinggi. Kajian ini menggunakan campuran bahan penjerap semulajadi terdiri daripada tanah liat, zeolit dan karbon teraktif bagi menjerap bahancemar tersebut. Ujian pencirian penjerap komposit telah dilakukan dengan menggunakan pendarkilau sinar-x (XRF), mikroskop imbasan elektron (SEM), luas permukaan Brunauer Emmett Teller (BET), titratan Boehm, pH di caj titik sifar (pHzpc) kelajuan goncangan, masa sentuhan, saiz partikel dan dos penjerap. Kelajuan goncangan adalah pada 200 rpm, masa sentuhan 120 minit, pH 7 dan saiz partikel 2.36-3.35 mm. Sementara ujian nisbah optimum dijalankan melalui penjerapan kelompok. Keputusan analisa kajian mendapati, tanah liat dan zeolit bleh dikategorikan sebagai penjerap hidrofilik dan karbon teraktif pula penjerap hidrofobik dengan nisbah optimum pada nisbah 5:3 sesuai dengan tingkah laku penjerapan NH3-N dan COD ke atas penjerap. Keputusan ujian XRF komposit penjerap menunjukkan kehadiran kalsium oksida dan silika oksida yang tinggi sebagai sebatian utama. Ujian SEM pula menunjukkan penjerap komposit mempunyai permukaan liang yang heterogen dan kasar. Kajian perbandingan menunjukkan kapasiti penjerapan penjerap komposit terhadap NH3-N dan COD adalah lebih baik daripada zeolit dan karbon teraktif. Kajian kinetik penjerapan mendapati penjerap komposit mengikut hampir kesemua model yang dikaji namun model pseudo-tertib kedua adalah paling dominan untuk keseluruhan parameter

Di Taman Universiti, air kelabu disalurkan terus ke longkang tanpa dirawat menyebabkan pencemaran kualiti air. Tujuan utama kajian ini adalah untuk membandingkan kebolehjerapan bahan penjerap semula jadi dan untuk menentukan peratus keberkesanan bahan penjerap dalam menyingkirkan permintaan oksigen kimia, COD dalam air kelabu. Kaedah penjerapan menggunakan zeolit, karbon teraktif dan tanah liat dan kaedah reka percubaan, DOE digunakan bagi mendapat nisbah penjerap yang akan digunakan. Peratusan penyingkiran COD adalah 79.41% dan kapasiti penjerapan adalah 0.54 mg/g untuk kaedah penjerapan menggunakan media komposit campuran zeolit, karbon teraktif dan tanah liat merupakan campuran yang terbaik. Penggunaan penjerap komposit yang mengandungi permukaan hidrofilik dan hidrofobik lebih berkesan sebagai penjerap yang berkesan dan dapat mengurangkan serta menyingkirkan COD yang berada dalam air.

A novel approach for the low-cost bioadsorbent for the removal of leachate pollutants is presented herein. In this study, limestone is combined with zeolite in order to fabricate biocomposite media with different ratios. Results revealed that limestone-zeolite biocomposite adsorbed ammoniacal nitrogen (NH3-N) and COD, which could possibly be used for the adsorption of NH3-N and COD efficiently from leachate. The optimum mixing ratio by means was carried out using series of batch experiments for limestone and zeolite to measure the remediation of NH3-N and COD in a stabilized leached. The optimum ratio for limestone and zeolite in the remediation of NH3-N and COD obtained were at 25:15 (82%) and 30:10 (75%), respectively. Indeed, the prepared limestone-zeolite biocomposite is a low-cost and effective adsorbent was potential used to derive the NH3-N and COD for a promising adsorption efficiency from stabilized landfill leachate.

Leachate are very high strength wastewaters that contain a variety of pollutants that pose a serious threat to the environment if appropriate control measure is ignored. Composite adsorbent is an emerging, interesting and attractive alternative to conventional adsorbents and having the ability to act as catalysts due to their high reactivity and excellent selectivity towards specific pollutant compounds. This study investigated the potential of biocomposite adsorbent made from a combination of chitosan, feldspar and zeolite (CFZ) for the treatment of Iron (Fe) from leachate wastewater. Leachate characterization and batch adsorption experiments was conducted to determine the optimum conditions for pH, dosage and contact time parameter in the removal of Fe. The result shows that the concentration of Fe was 15.82 which exceeded the recommended limit. The optimum conditions also occurred at pH 5 with 6 gram of biocomposite dosage and at 180 minutes contact time. The corresponding removal efficiency for Fe is 90% with 0.0127 mg/g uptake capacity

Plant waste such as Delonix Regia Pods have the potential to be used as absorbents. A study of activated carbon derived from delonix regia pods was carried out for the removal COD in natural rubber wastewater. Sample wastewater was obtained from the rubber processing industry and characterized to determine the level of pollutant content. Results of the analysis of wastewater characterization shows that the COD value was 5196 mg/L which is above discharge standards. Laboratory experiments was conducted to determine the optimum dosage, pH, shaking speed and contact time using response surface methodology. The results showed that the optimal dosage, pH, shaking speed and contact time were 4 g, pH 8, 150 rpm and 100 minutes with COD removal value of 70.65 %. The model F-value obtained for COD was 68.27 with the Prob. > F value of < 0.0001 indicating the significance of the model. The predicted versus the empirical data were relatively close to each other, therefore the developed models sufficiently described the response and variables interaction in the adsorption process. The results also indicate the suitability of the adsorbent for application in a sustainable wastewater treatment. It is recommended that further study be carried out to assess its application for other pollutants derived from non-rubber industries.

Waste paper sludge (WPS) is produced by the paper industry during the wastewater treatment process of paper production. The disposal techniques of WPS pose a great concern for the environment. This study focuses on the evaluation of WPS as an alternative absorbent material to activated carbon (AC) for the removal of contaminants from stabilized landfill leachate. Ammonia nitrogen (NH3-N) and chemical oxygen demand (COD) were identified as the two major contaminants in landfill leachate. Both AC and WPS were mixed together in different ratios. The optimum replacement for the absorbent was determined using the batch technique. The adsorption batch study was carried out under the optimum pH of 7, with a shaking speed of 200 rpm and a contact time of 120 minutes. The adsorption isotherms indicated that the Langmuir model was better fitted to the experimental data as it was found to have the highest regression values. The Langmuir adsorption capacities for COD and NH3-N were 32.26 mg/g and 21.60 mg/g, respectively. The optimum replacements were initially at two different ratios of 2:2 and 3:1 based on the optimum removal of COD and NH3-N, respectively. However, the final optimum replacement for the absorbents (AC: WPS) in this study was the ratio of 2:2 due to the higher removal of COD (85.9%) and NH3-N (49.3%).

This research was carried out to investigate the effects of hooked-end steel fibers on compressive and flexural strength of concrete containing palm oil biomass clinker (POBC) as partial replacement of fine aggregates. The optimum percentage of POBC was taken as 10%, to replace natural sand on the basis of trial mixes. Due to the porous characteristic of POBC, hooked-end steel fibers were added to improve the flexural strength of concrete. For this research, the concrete mixture containing 10% of POBC with varying percentages of the hooked-end steel fibers i.e. 0.2%, 0.4% and 0.6% by weight was produced. Total 48 specimens were prepared, 24 concrete cubes for compressive strength and 24 prisms were prepared for flexural strength at 7 days and 28 days. Hence, it was evaluated that the reduction of workability in concrete with the addition of steel fibers. Furthermore, The maximum flexural strength were recorded as 2.54 MPa with 0.4% hooked-end steel fibers at 28days and maximum compressive strength of was recorded as 27.51 MPa with 0.6% Â hooked-end steel fibers at 28days. It is concluded that the hooked-end steel fibers has good potentiality to enhance the compressive as well as flexural strength of concrete.

The optimal conditions for the reduction of COD and NH3-N using cockle shells (CS) from a stabilised landfill effluent were analyzed. The influence of two variables (adsorbent dosage and pH) were analysed through the application of response surface methodology (RSM) and central composite design (CCD). Quadratic models were developed for the removals of COD and NH3-N parameters. The optimum conditions for removal of 65.6% and 53.6% for COD and NH3-N respectively was achieved at pH 6.34, adsorbent dosage of 20.21 g having 0.888 desirability value. The model F-value obtained for NH3-N removal Prob. > F value of 0.0001 with F-value of 104.21 was obtained. Similarly the Prob. > F value of < 0.0001 for COD with F-value of 82.74 was obtained, these P-values confirmed the significance of the model. The predicted response versus the experimental response depicted that the experimental data were relatively close to the predicted data. Thus, the generated models significantly enclosed the correlation between the process variables and the response.   GMT Detect languageAfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGermanGreekGujaratiHaitian CreoleHausaHebrewHindiHmongHungarianIcelandicIgboIndonesianIrishItalianJapaneseJavaneseKannadaKazakhKhmerKoreanLaoLatinLatvianLithuanianMacedonianMalagasyMalayMalayalamMalteseMaoriMarathiMongolianMyanmar (Burmese)NepaliNorwegianPersianPolishPortuguesePunjabiRomanianRussianSerbianSesothoSinhalaSlovakSlovenianSomaliSpanishSundaneseSwahiliSwedishTajikTamilTeluguThaiTurkishUkrainianUrduUzbekVietnameseWelshYiddishYorubaZulu AfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGerm

Natural rubber processing wastewater contains high concentration of organic compound, colour, nitrogen, and other contaminants. This study evaluated a chitosan bead as an adsorbent in adsorption process for natural rubber wastewater treatment. The effects of adsorbent dosage, pH, shaking speed and contact time and adsorption isotherm on colour adsorption onto chitosan beads were evaluated using batch experiments. Meanwhile, Langmuir and Freundlich isotherm models were used to validate the experimental data. Maximum removal of 71.5%, for colour was observed for an adsorbent dosage 4.5 g, pH 7, and shaking speed 150 rpm. Equilibrium was achieved in 120 min. The equilibrium data were fitted to Langmuir isotherm model when compared with Freundlich isotherm models.

The objective of this study was to identify the performance of empty fruit bunch (EFB) to assess its use as potential adsorbent in treat ammonia nitrogen in natural rubber wastewater. The adsorption method was employed to investigate the effect of a number of factors, namely, adsorbent dosage, pH, shaking speed and contact time. The results revealed that the removal of ammonia nitrogen up to 79.5% from natural rubber wastewater. The adsorption efficiency of EFB fibre was maximum at 3.5 g dosage, pH 7, 150 rpm shaking speed and 120 min contact time. The results proved that EFB fiber are good alternative low cost adsorbent for the removal of ammonia nitrogen from natural rubber wastewater. The Langmuir isotherm (R2=0.9923) described ammonia nitrogen adsorption slightly better than the Freundlich isotherm (R2 = 0.9450), suggesting a monolayer adsorption behaviour of the adsorption processes.

Leachate is a liquid generated due to rainwater percolation through the wastes in a landfill or dumping site that may contain high levels of organic matter including both biodegradable and non-biodegradable which major source of water pollution. In this research work, landfill leachate has been characterized and found to contain very high COD and color. Adsorption process was performed to find out the performance of different combinations ratio between limestone (LS) and zeolite (ZEO). The removal efficiencies of different ratios were examined for reduction of COD and color. The optimum mixture ratio of adsorbents (LS:ZEO) at 10:30 and 15:25 were found to be more effective in reducing COD and color respectively as compared with the use of individual media. The highest removal percentage were found at approximately 55% of COD and 76% of color with 120 minutes of contact time, 200 rpm in shaking speed at pH7. The Langmuir adsorption isotherm model exhibited a better fit with high correlation R2=0.9991 for COD and R2=0.9827 for (color) respectively, which implies that the adsorption of leachate in this study onto LS-ZEO is homogeneous with monolayer. It was observed that limestone and zeolite mixture provides an alternative medium for removing COD and color at a considerably lower cost.

This paper presents experimental investigations on the crushing performances of axially compressed woven kenaf fibre reinforced cylindrical composites. Based on the literature survey, there are tremendous amount of work are available on the crushing performances regardless whether the composite contained synthetic or natural fibers. However, lack number of work found in discussing the crushing capability for the composite tubes fabricated using woven kenaf mat reinforced composites. Kenaf fibre in the form of yarn is weaved into a woven mat before it is submerged into a resin bath prior the mats are shaped to form a cylindrical tube. There are two important parameters are used such as number of layers and fiber orientations. The composite tubes are then quasi-statically compressed to obtain the force-displacement curves. Energy absorption capability and other crashworthiness parameters are calculated and discussed in term of number of layers and fiber orientations. According to the results, it is found that both number of layer and fiber orientations played an important role in an elastic region or the first region. On the other hand, in the second stage, it is insignificantly affected the plateau stage where the curves seemed not much different.

Leachate is one of the major problems to overcome in managing the landfill. Low cost treatment, less maintenance and environmental friendly are considered as the best practices to treat leachate. Without a proper treatment, leachate could give a negative effect to the environment and become a pollutant. This research focused on the effectiveness of Up-flow Anaerobic Sludge Blanket on leachate treatment using reactor tank in lab-scale. The effectiveness of this system was evaluated by comparing the percentage of nutrient removal. Moreover, leachate characteristic was conducted to determine the nutrient content. Five (5) main parameters were selected to be monitored which are Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Nitrogen (TN) and Total Phosphorus (TP). Experiments were run for 30 days and  the readings were recorded every 3 days. Results show that the capability of UASB in the removal several parameters. This UASB had a greater ability in removal of Total Phosphorus and TSS with 89% and 81% average removal each. COD removal shows encouraging removal graph more than 70%. While BOD, 64% and Total Nitrogen as 50%. Results showed that UASB system was capable to remove major pollutants from landfill leachate.

This paper reported the optimization of COD and NH3-N reduction from a stabilised leachate by zeolite (ZE) and moringa oleifera leaf powder (MP) mixture using response surface methodology (RSM) and central composite design (CCD). Quadratic polynomial equations were obtained for the removal process. An initial experiment was conducted to establish the optimum mixed ratio between ZE:MP and resulted in a ratio of 24:16. Independent variables investigated in the subsequent optimization experiments include pH ,dosage and contact time. The results revealed that the optimal reduction of COD and NH3-N from landfill leachate was considerable at pH 5.9 , optimal time of 113 minutes and 100gL-1 of adsorbent dosage with desirability value of 0.917. The upper limits for the actual versus predicted reduction were 70.14 against 69.13%Â and 86.94 against 86.55 % respectively for COD and NH3-N which defined that the experimental values were relatively close to the predicted values. The study also revealed that ZE:MP mixture has a very high potential for the remediation of COD and NH3-N from a stabilized leachate.

Natural rubber processing wastewater contains high concentration of organic compound, colour, nitrogen, and other contaminants. This study evaluated a chitosan bead as an adsorbent in adsorption process for natural rubber wastewater treatment. The effects of adsorbent dosage, pH, shaking speed and contact time and adsorption isotherm on colour adsorption onto chitosan beads were evaluated using batch experiments. Meanwhile, Langmuir and Freundlich isotherm models were used to validate the experimental data. Maximum removal of 71.5%, for colour was observed for an adsorbent dosage 4.5 g, pH 7, and shaking speed 150 rpm. Equilibrium was achieved in 120 min. The equilibrium data were fitted to Langmuir isotherm model when compared with Freundlich isotherm models.

Landfills generate leachate that contains elevated concentration of contaminants and is hazardous to human health and the ecosystem. In this study, the mixture of granular feldspar and cockle shells was investigated for remediation of COD and ammonia from landfill leachate. All adsorbent media were sieved to a particle size between 2.00 and 3.35 mm. The results revealed that the optimum mixing ratio of feldspar and cockle shells was 20:20, shaking speed was 150 rpm, pH level was 6, shaking time was 120 min, and dosage was 30 g. The adsorption isotherm analysis reveals that the Langmuir isotherm yielded the best fit to experimental data as compared to the Freundlich isotherm. The media produce encouraging results and can potentially be used as a good and sustainable adsorbent.

The potential of Empty Fruit Bunch obtained from palm oil tree as a low-cost adsorbent is a sustainable approach in wastewater treatment. The objective this study to investigate the capability of EFB for removal colour from natural rubber wastewater as well as the influence of adsorbent dosage, pH, shaking speed and contact time. The results of the analysis show that all selected factors exhibit significant effect on removal of colour. Maximum removal (87.1%) for colour was achieved at 3.5 g of adsorbent dosage, pH 7, 150 rpm of shaking speed, 120 min of contact time. The Langmuir isotherm (R2 = 0.9913) described colour adsorption slightly better than the Freundlich isotherm (R2 = 0.9805), suggesting a monolayer adsorption behavior of the adsorption processes.

Pulp and paper production from wood material as their main resources have a total capacity about more than one million tons per year. Malaysia has a high scale of deforestation based on the main resource for pulp and paper-based industry. Malaysia as its rate is accelerating faster than any other tropical countries in the world. This problem also affects the economic losses of some countries that face deforestation. To overcome this, Napier grass as a substitute material from non-wood material had been choose for pulp and papermaking industry. This study through the full fibre analysis and morphological characterization, pulpability at kappa number via soda-AQ pulping and the characteristic. These conclude that Napier grass had a high percentage of pulp yields; with a low screening rejects; good mechanical properties by TAPPI method. Thus, Napier grass has a potential to be substitute material for becoming waste-wealth product especially for Malaysia’s pulp and papermaking industry.

Greywater is a wastewater originating from shower, bathtub, bathroom sink, kitchen sink and laundry. Despite the fact of wastewater in Malaysia may also include a complex mixture of organic matter, suspended solids, bacteria and common household chemicals, when used wisely and in a manner that is protective to public health and the environment, it can helps preserve limited water supply. This study aims the efficiency of adsorption of organic pollutants in greywater by using natural fibers such as Kenaf dust and Chitosan powder to treat the colour of water and the cause of odours from the greywater. The objective of this research is to identify the characteristics of greywater according to standard effluent discharge, as well as to characterize the physical properties of Kenaf (Hibiscus Cannabinus L.) and to determine the percent removal parameters of greywater by using Kenaf dust and Chitosan powder as organic removal. Raw greywater samples were taken at main drain Kompleks Parit Raja. The results for raw greywater samples obtained such as COD (253 mg/l), TSS (1800 mg/l), pH (5.89) and turbidity (47.5 NTU) were compared to Effluent Standard Discharge (EQA 1974). The COD removal efficiencies by using kenaf dust and chitosan powder amounted to 51% and 50 %, also TSS removal 89% and 100%. The pH and turbidity amounted to 6.76 and 7.04, 46 NTU and 4.46 NTU respectively. The overall removal of organic pollutants increased with different mass of adsorbents, then the optimum adsorbents were selected 30%, 40% and 50% to form as beads.

Leachate are very high strength wastewaters that contain a variety of pollutants that pose a serious threat to the environment if appropriate control measure is ignored. Composite adsorbent is an emerging, interesting and attractive alternative to conventional adsorbents and having the ability to act as catalysts due to their high reactivity and excellent selectivity towards specific pollutant compounds. This study investigated the potential of biocomposite adsorbent made from a combination of chitosan, feldspar and zeolite (CFZ) for the treatment of Iron (Fe) from leachate wastewater. Leachate characterization and batch adsorption experiments was conducted to determine the optimum conditions for pH, dosage and contact time parameter in the removal of Fe. The result shows that the concentration of Fe was 15.82 which exceeded the recommended limit. The optimum conditions also occurred at pH 5 with 6 gram of biocomposite dosage and at 180 minutes contact time. The corresponding removal efficiency for Fe is 90% with 0.0127 mg/g uptake capacity.

Leachate are very high strength wastewaters that contain a variety of pollutants that pose a serious threat to the environment if appropriate control measure is ignored. Composite adsorbent is an emerging, interesting and attractive alternative to conventional adsorbents and having the ability to act as catalysts due to their high reactivity and excellent selectivity towards specific pollutant compounds. This study investigated the potential of biocomposite adsorbent made from a combination of chitosan, feldspar and zeolite (CFZ) for the treatment of Iron (Fe) from leachate wastewater. Leachate characterization and batch adsorption experiments was conducted to determine the optimum conditions for pH, dosage and contact time parameter in the removal of Fe. The result shows that the concentration of Fe was 15.82 which exceeded the recommended limit. The optimum conditions also occurred at pH 5 with 6 gram of biocomposite dosage and at 180 minutes contact time. The corresponding removal efficiency for Fe is 90% with 0.0127 mg/g uptake capacity.

Waste paper sludge (WPS) is produced by the paper industry during the wastewater treatment process of paper production. The disposal techniques of WPS pose a great concern for the environment. This study focuses on the evaluation of WPS as an alternative absorbent material to activated carbon (AC) for the removal of contaminants from stabilized landfill leachate. Ammonia nitrogen (NH3-N) and chemical oxygen demand (COD) were identified as the two major contaminants in landfill leachate. Both AC and WPS were mixed together in different ratios. The optimum replacement for the absorbent was determined using the batch technique. The adsorption batch study was carried out under the optimum pH of 7, with a shaking speed of 200 rpm and a contact time of 120 minutes. The adsorption isotherms indicated that the Langmuir model was better fitted to the experimental data as it was found to have the highest regression values. The Langmuir adsorption capacities for COD and NH3-N were 32.26 mg/g and 21.60 mg/g, respectively. The optimum replacements were initially at two different ratios of 2:2 and 3:1 based on the optimum removal of COD and NH3-N, respectively. However, the final optimum replacement for the absorbents (AC: WPS) in this study was the ratio of 2:2 due to the higher removal of COD (85.9%) and NH3-N (49.3%).

The objective of this study was to identify the performance of empty fruit bunch (EFB) to assess its use as potential adsorbent in treat ammonia nitrogen in natural rubber wastewater. The adsorption method was employed to investigate the effect of a number of factors, namely, adsorbent dosage, pH, shaking speed and contact time. The results revealed that the removal of ammonia nitrogen up to 79.5% from natural rubber wastewater. The adsorption efficiency of EFB fibre was maximum at 3.5 g dosage, pH 7, 150 rpm shaking speed and 120 min contact time. The results proved that EFB fiber are good alternative low cost adsorbent for the removal of ammonia nitrogen from natural rubber wastewater. The Langmuir isotherm (R2 =0.9923) described ammonia nitrogen adsorption slightly better than the Freundlich isotherm (R2 = 0.9450), suggesting a monolayer adsorption behaviour of the adsorption processes.

The optimal conditions for the reduction of COD and NH3-N using cockle shells (CS) from a stabilised landfill effluent were analyzed. The influence of two variables (adsorbent dosage and pH) were analysed through the application of response surface methodology (RSM) and central composite design (CCD). Quadratic models were developed for the removals of COD and NH3-N parameters. The optimum conditions for removal of 65.6% and 53.6% for COD and NH3-N respectively was achieved at pH 6.34, adsorbent dosage of 20.21 g having 0.888 desirability value. The model F-value obtained for NH3-N removal Prob. > F value of 0.0001 with F-value of 104.21 was obtained. Similarly the Prob. > F value of < 0.0001 for COD with F-value of 82.74 was obtained, these P-values confirmed the significance of the model. The predicted response versus the experimental response depicted that the experimental data were relatively close to the predicted data. Thus, the generated models significantly enclosed the correlation between the process variables and the response.

Micro-peat (M-P) was demonstrated in the present study as a potential low cost natural adsorbent for the removal of COD and ammoniacal nitrogen (NH3-N) from landfill leachate. A series of batch experiments were carried out under fixed conditions and the influence of mixture ratio was investigated. The characteristics of leachate were then determined. Results indicated that leachate is non-biodegradable with high concentration of COD (2739.06 mg/L), NH3-N (1765.34 mg/L) and BOD5/COD ratio (0.09). The optimum ratio for activated carbon (AC) and M-P in the removal of COD and NH3-N obtained were at 2.5:1.5 (87%) and 1.0:3.0 (65%) respectively. The low-cost natural adsorbent used in the present investigation is an attractive alternative to the conventional adsorbent (AC). Thus, M-P can be appropriated for use in leachate treatment that could be cost-effective due its local availability and adsorption property.

The vigorous combination of waste in landfill recognized as potential hazard source, but one distinctive problem associated with landfill is leachate. Zeolite is known as good adsorbent but the cost is relatively high. Feldspar is the most abundant mineral group in the world, forming around 60% of the earth’s crust. Due to its availability, feldspar becomes one of low cost materials. Feldspar and zeolite is combining as an composite adsorbent in this study where there optimum ratio between this material is determined. The experimentcarried out in a series of 250 mL conical flask with varied amount of media ratio shaken for 5 hours with 200 rpm shaking speed and at pH 7. The best ratio of feldspar and zeolite chosen is 1:1 according to the adsorption behavior of organic constituent (COD) and ammoniacal nitrogen (NH3-N) to the media. The value of the removal percentage of COD and NH3-N is 49% and 45% respectively and the uptake capacity for both contaminant is 50.14 mg/g and 8.06mg/g respectively.  The usage of feldspar will significantly reducing zeolite usage conventionally and consequently decresing the operational cost in leachate treatments

The use of zeolite, clay and activated carbon media in wastewater treatment and leaching has become increasingly popular today as it has the potential to improve water quality, as well as low maintenance and operating costs. This study aims to determine the optimum mix media of the adsorption agent and determine the mineral content in the adsorption agent using XRF and SEM, in addition, determine the cation exchange capacity (CEC) value of the adsorbent and determine the kinetic model of adsorbent material on the removal of COD and Ammonia. The leachate sample was taken from the CEP landfill, Machap, Johor, Malaysia. Mixed media design of adsorbent material is in percentages of 0%, 40%, 60%, 80% and 100%. Each set will be tested on touch time for 2 hours, 4 hours and 8 hours. The parameters to be performed are chemical oxygen demand (COD), turbidity, ammonia nitrogen and pH. The results showed that the optimum touch time for the removal percentage was at 8 hours of touch time. On the first backwash method and the second backwash find the optimum touch time at 4 hours of touch time. The removal rate for ammonia and chemical oxygen demand reaches the removal target of 80% removal.

This paper reviews and extends an understanding of a study on potential suitability of the natural soil in Endau Rompin National Park (PETA) as a compacted soil liner for sanitary landfill. Since the demand for landfill system becomes obvious so that concerning construction and operation of landfills are increasing. A number of studies have been conducted for the liner system of landfill. Hence, study is required to choose the suitable type of material as liner barrier for the landfill system in term to achieve optimum long term performance. The sanitary landfill plays an important role in the framework of solid waste disposal. The compacted soil liner is a part of a liner structure for landfill to restrict leachate migration from facility into the environment. So that, if the landfill system is not well manage it will contaminate the soil and ground water, thus presenting a risk to human and environmental health. This study, natural soil will be taken from Endau Rompin National Park (PETA), Johor as soil sample for testing. Natural soil is an economy material as a liner system, and it does not decay easily from time to time. So it is an ideal material as a sanitary landfill liner system. In short, the purpose of this study is to compile and organize available information on the use of laboratory testing, as well as providing some guidance on the use of natural soil as barrier layer of landfill and also it suitability of physical and chemical properties natural soil as barrier layer of landfill. Based on the laboratory testing were conducted, found that soil sample taken form Endau Rompin National Park (PETA) is suitable as compacted soil liner for sanitary landfill. &nbsp

Laboratory studies have shown phytoremediation is a feasible method for remediating sludgecontaminated with heavy metals. This research focused on the ability of plants to hydroponically treat digestedindustrial sludge contaminated with aluminium (Al), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), lead(Pb), nickel (Ni), manganese (Mn) and zinc (Zn). The sludge used in the study was obtained from the wastewatertreatment lagoon of a textile factory. Three species were used in the phytoremediation process. They were CyperusKyllingia-Rasiga, Asystassia Intrusa and Scindapsus Pictus Var Argyaeus. These species were planted inhydroponic pots placed under a transparent roof to allow natural light. In the first batch, pots containing 2 seedlingsof each plant were applied with 9.81 mg, 12.83 mg, 15.85 mg, 18.87 mg and 21.9 mg digested dried industrialsludge. In the second batch, the pots planted with 1, 2, 3, 4 and 5 seedlings and were applied with the same amountof 21.9 mg of digested industrial sludge each. The pH and electrical conductance (EC) of hydroponic solution weremonitored in this phytoremediation processes. The results showed that the absorption of heavy metals byAsystassia Intrusa was in the order of Mn > Al > Cu > Fe > Ni > Zn > Cd > Pb > Cr, with medium pH and EC of6.90 ± 0.73 and 2.47 ± 1.96 μS/cm respectively . The absorption of heavy metals by Cyperus Kyllingia-Rasigawas in the order of Mn > Cu > Ni > Cr > Pb > Zn > Fe > Al > Cd at medium pH 6.87 ± 0.71 and EC 2.72 ± 1.85μS/cm and the absorption by Scindapsus Pictus Var Argyaeus was in the order of Cu > Ni > Mn > Pb > Zn > Cr >Cd > Al > Fe at neutral pH and the EC 2.72 ± 1.71 μS/cm. From the study it was concluded that the plant speciesused were able to significantly absorb the metals present in industrial sludge.

Kehadiran logam berat di dalam enapcemar domestik menyukarkan proses rawatan dan pelupusan bahan tersebut. Salah satu kaedah yang berkesan ialah melalui pengaplikasian bahan tersebut kepada tanah pertanian. Kaedah ini dipilih berdasarkan kandungan enapcemar yang mempunyai unsur nutrien yang diperlukan untuk tumbesaran tumbuhan, selain menggalakkan proses kitar semula bahan terbuang disamping kos pengendalian yang rendah. Kajian ini bertujuan untuk menentukan kandungan logam berat di dalam enapcemar domestik dan mengolahnya melalui kaedah tanah pertanian. Kajian ditumpukan kepada enapcemar domestik daripada empat (4) jenis loji rawatan iaitu enapcemar teraktif, kolam pengoksidaan, lagun berudara dan tangki septik. Enapcemar diaplikasikan kepada tanah pertanian pada kadar 0 tlm2, 2 tlm2, 4 tlm2, 6 tlm2, 8 tlm2 dan 10 tlm2 secara semburan permukaan kepada sel aplikasi yang berkeluasan 0.091 m2 • Sel-sel ditanam dengan tigajenis tanaman secara berasingan iaitu kangkung (ipomoea aquatica), bayam (spinacea oleracea) dan sawi (brassicajuncea) dan ditempatkan di kawasan yang terbuka dengan dilindungi oleh bumbung telus cahaya supaya menyamai persekitaran semulajadi dan membenarkan kawalan kelembapan tanah dilakukan pada 60 peratus. Analisis penyerapan logam berat oleh tumbuhan kajian dilakukan terhadap tiga keratan rentas iaitu bahagian akar, batang dan daun tumbuhan. AnaIisis yang dilakukan melalui peralatan Plasma Gandingan Aruhan - Spektrometer Jisim, (ICPMS) mendapati enapcemar domestik mengandungi logam aluminium (AI), kadmium (Cd), kromium (Cr), kuprum (Cu), ferum (Fe), plumbum (Pb), nikel (Ni), mangan (Mn), dan zink (Zn). Pengambilan logam oleh tumbuhan kajian pada kadar aplikasi enapcemar yang berbeza menunjukkan wujudnya hubungan di antara parameter tersebut secara polinomiaI. Sementara kajian pemekatan logam pada bahagian tumbuhan mendapati logam lebih cenderung untuk memekat pada bahagian akar berbanding batang dan daun tumbuhan. Secara keseluruhannya, kajian ini