Development of Natural Fiber as a Filter Media in Removing Organic Pollutants from Greywater

Mohd Baharudin Ridzuan1,a, Zawawi Daud1,b, Zulkifli Ahmad1,c, Nurul Amira Md Nordin1,d and Zulfairul Zakariah2,e

1Team of Research in Integrated Solid Waste Management (TRISM), Faculty of Civil and Environment Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja,

Batu Pahat, Johor, Malaysia 2University Technology MARA (Pulau Pinang), Jalan Permatang Pauh, 13500 Permatang Pauh,

Pulau Pinang, Malaysia amdbahar@uthm.edu.my, bzawawi@uthm.edu.my, czul@uthm.edu.my,

dnurulamira1307@yahoo.com, ez.fairul@yahoo.com

Keywords: Natural fiber, Organic Pollutants, Greywater.

Abstract. 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.

Introduction

The growing population and rapid development in urban areas have increased the demand of uninterrupted supply of clean water. The initiative also aims to increase the coverage of water supply up to 100%, especially in urban areas and raise treated water supply reserves nationwide to 20%. Despite this remarkable achievement, there are several issues that affect uninterrupted clean water supply to urban and rural areas, such as pollution, non-revenue water (NRW), insufficient water reserves and high water demand.

Greywater is defined as wastewater without any input from toilets, which means that it corresponds to wastewater produced in bathtubs, showers, hand basins, laundry machines and kitchen sinks, in household, office buildings, and schools [1]. The potential of greywater process as well as the major influence of parameters such as carbon oxygen demands (COD), total suspended solids (TSS), pH, and turbidity were investigated in this research for the treatment of greywaters of low and high organic strength.

Kenaf (Hibiscus cannabinus L.) was found as a native plant in Eastern Africa (Kenya and Tanzania) and has been produced commercially on a plantation in Tanzania, from a cultivar developed in Guatemala [2]. According to [3], the natural fiber of Kenaf is an effective adsorbent for

Defect and Diffusion Forum Submitted: 2017-09-19ISSN: 1662-9507, Vol. 382, pp 302-306 Accepted: 2017-09-25doi:10.4028/www.scientific.net/DDF.382.302 Online: 2018-01-10© 2018 Trans Tech Publications, Switzerland

All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TransTech Publications, www.scientific.net. (#106823010, Chalmers University of Technology, Göteborg, Sweden-14/02/18,09:47:29)

both anionic and cationic pollutants and also for heavy metals removal from wastewater. In this study, the potential of kenaf fibre was explored to enhance it’s beneficial use especially in greywater treatment process.

Materials and Methods

The experiment was conducted by optimize and investigate the influence of adsorbents during the treatment process. 100ml of greywater samples was filled with each adsorbent from 1g to 5g in 150 rpm shaker for 24 hours. From this treatment, the optimum conditions of each adsorbent have been selected for kenaf dust filled with chitosan powder in beads preparation. Then, the same treatment was conducted for beads adsorbent. Kenaf dust fibers were supplied by Lembaga Kenaf & Tembakau Negara (LKTN), Malaysia and Chitosan powder was purchased from Kitosan Sdn. Bhd., Malaysia. Kenaf dust washed by hot distilled water for many times until the color from the fiber being rinsed. Then, dried under sunlight for about two days. After that, soaked the kenaf dust in the 0.1 M sodium hydroxide (NaOH) with 1L distilled water. Chitosan solution was prepared by dissolving chitosan powder in 5 ml aceatic acid and 80 ml distilled water with every 10% to 100% of chitosan to fill with kenaf dust. The chemical composition of the fibers such as cellulose, hemicelluloses and lignin were determined by using the standard methods: T 222 om-06, Chlorination and Kurschner-Hoffner Methods [4]. The composition of adsorbent obtained from effective optimum adsorbent that has high percent removal. Then, use a syringe for making a beads by drop one by one in sodium hydroxide solution (NaOH).

Fig. 1 Kenaf dust filled with Chitosan powder as beads before and after drying.

Results and Discussions

Natural Fibers. Natural fibers contain cellulose, hemicelluloses, pectins and lignin and are rich in hydroxy1 groups; natural fibers tend to be strong polar and hydrophilic materials whilst polymer materials are a polar and exhibit significant hydrophobicity [5]. Kenaf (Hibiscus cannabinus, L. family Malvacea) has been found to be an important source of fiber for composites, and other industrial applications [6]. In order to develop composites with better mechanical strength, it is necessary to impart hydrophobicity to the fibers through surface treatment. Natural fibers can be modified either by physical or chemical means [7]. For this study we were using chemical method as surface treatment. Alkaline treatment (mercerization) is a well-known chemical treatment of surface modification of natural fiber to make natural fiber reinforced polymer [8]. The chemical modifications of fibres were carried out in order to improve mechanical properties of composites and adhesion between the fibres and matrix [9]. The biodegradable composites of kenaf and chitosan in this study was prepared via solution blending method. In the solid state, chitosan is a semicrystalline polymer [chitin]. Chitosan is highly compatible with other biopolymers thus its blending with cellulose and/or incorporation of nanofiber isolated from cellulose namely cellulose nanofiber and cellulose nanowhiskers are generally useful [10]. Addition of kenaf dust into chitosan powder

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increases the stability towards hydrolysis in greywater treatment. From the observation, the concentration of acidic and alkali solution played an important role for blending the composites of kenaf dust and chitosan powder.

SEM Morphology. The fibers (treated) and chitosan dust was tested by using SEM to get the morphology image of the adsorbents. The chemical modification changes the surface of the fibres from smooth to irregular, often porous [11]. The scanning electron microscope (SEM) analysis enables the direct observation of the surface microstructure of the composite adsorbent. Fig. 2 (a) and (b) present SEM micrographs of the Kenaf dust. The surface of kenaf as shown in Fig. 2 (a) became rough and some has irregular pores and not have smooth surface. In Fig. 2 (b) was highly packed, porousness and having no cavities. It can be seen that the chemical surface treatment causes a clean and rough surface on the fibre which is so important for interfacial bonding of polymer and kenaf fibers. From Fig. 3 (a) and (b) showed that chitosan powder has high porosity and has spongy surface structure.

Fig. 2 (a) and (b) The morphological structure of Kenaf dust by SEM analysis.

Fig. 3 (a) and (b) The morphological structure of Chitosan powder by SEM analysis.

Characteristics of Greywater Sample. The results of this parameter had been taken as guidance to evaluate the contaminants of greywater and the efficiency of kenaf and chitosan as organic removal. These were Chemical oxygen demand (COD), Total suspended solids (TSS), pH and turbidity. It was analysed and compared with Effluent Standards Discharge from Environmental Quality Act 1974 and previous study by [12] and [13] for greywater characteristics from the sources before using kenaf dust and chitosan powder for treatment (Table 1).

(a)

(a)

(b)

(b)

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Table 1 The characteristics of raw greywater from effluent standard discharge and previous study.

Parameter

Effluent Standard Discharge

(EQA 1974)

From this study From previous study Raw Greywater

Samples Raw Greywater

Range By H. Al-Hamaiedeh et al,.

2009

Grey Wastewater By Thirugnanasam et al,.

2013

COD (mg/l) 100 253 92-2263 646 TSS (mg/l) 100 1800 23-358 - pH value 5.5-9.0 5.89 6.9-7.8 5.78 Turbidity

(NTU) - 47.5 - 35

The greywater has been treated by using adsorbent such as kenaf dust and chitosan powder and combination of kenaf with chitosan (beads) as organic removal in this treatment. These parameters were Chemical oxygen demand (COD), Total suspended solids (TSS), pH and turbidity. The removal percentage is shown in the Table 2.

Table 2 Optimum values of Percent Removal Parameters. Parameters Kenaf Dust Chitosan Powder

COD removal (%) 51 50

TSS removal (%) 89 100

Turbidity removal (%) 3.16 90.6

Pollutant Removal From Greywater by Natural Fiber. Kenaf dust is an important factor, which influences the treatment of greywater. However, in this study were discussed in term of the highest COD removal, TSS removal and turbidity removal efficiency for greywater treatment. COD was reduced to 51% (less than 253 mg/l from the sample). Turbidity removal in this results were less than the TSS results removal as it reduced to 89% from the treatment. Thus, it shows that kenaf dust was expected to tolerate with its dimension in holding the contaminants occurs from the greywater. Chitosan powder was performed as binder to kenaf dust in the treatment. According to that, the experiment were conducted to analysis the capability of chitosan powder in greywater treatment. The results (Table 2) shows the highest of COD removal, TSS removal and turbidity removal were 50%, 100% and 95% respectively. This showed that the chitosan has lower in moisture adsorption and swelling as the turbidity removal was less than TSS removal. According to [14], the rate of water absorption for kenaf-filled chitosan composites could be conveniently divided into three main phases. Phase one is corresponding to the highest rate of water absorption occurring during the first 5 min of immersion time. In this phase, the increasing rate of water absorption was observed with time. The second phase, where the rate of water absorption is slower than the first phase with decreasing rate, was observed with time until the equilibrium state is reached. Phase three is where the rate of water absorption is zero and there is no longer water absorption occurring and the water content in the specimen becomes saturated.

Conclusions

In this study, it showed that the result of raw greywater samples collected was exceed the effluent standard discharge. So, it caused a higher contaminants in the greywater samples. Kenaf dust and Chitosan powder have been successfully remove the contaminants from the samples. From the results obtained, Kenaf dust and Chitosan fibre were able to remove total suspended solids at 89 % and 100 % respectively. For COD parameter, both natural fibres were able to reduce more than 50 % samples concentration. On the hand, chitosan powder showed a great removal in turbidity with up to 90 % removal.

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Acknowledgements

The authors would like to acknowledge the Ministry of Higher Education, Malaysia and University Tun Hussein Onn Malaysia (UTHM) for the financial support in completing this study.

References

[1] Eriksson, E. et al., (2002). Characteristics of Greywastewater. Urban Wastewater, 4(1), pp. 85 – 104.

[2] Wilson, F. D. 1978. Wild kenaf, Hibiscus cannabinus L. (Malvaceae), and related species in Kenya and Tanzania. Economy Botany 32: pp. 199-204.

[3] Marcus J. Et al., (2013). International Journal of Science, Environment and Technology, Vol. 2, No 5, 2013, 805 – 812.

[4] Z. Daud, M.Z.M. Hatta, A.S.M. Kassim, H. Awang, A.M. Aripin: BioResources, 9 (2014), p. 872–880.

[5] Kasiviswanathan S.et. al, (2015) Evaluation of mechanical properties of natural hybrid fibers, reinforced polyester composite materials. Carbon e Sci Tech, 7(4).

[6] Karnani R, Krishnan M, Narayan R. Biofiber reinforced polypropylene composites. (1997), Polym Eng Sci, 37, pp. 476–83.

[7] K. Venkata Krishna, K. Nanny, (2016). The effect of treatment on kenaf fiber using green approach and their reinforced epoxy composites. Composites Part B, 104, pp. 111-117.

[8] R. Mahjoub et. al, (2014). Tensile properties of kenaf fiber due to various conditions of chemical fiber surface modifications. Construction and Building Materials, 55, pp. 103-113.

[9] Janusz Datta, Patrycja Kopczynska, (2015). Effect of kenaf fibre modification on morphology and mechanical properties of thermoplastic polyurethane materials. Industrial Crops and Products, 74, pp. 566-576.

[10] A.K. H.P.S et. al, (2016). A review on chitosan-cellulose blends and nanocellulose reinforced chitosan biocomposites: Properties and their applications. Carbohydrate Polymers, 150, pp. 216-226.

[11] G. Asiorowski et. al, (2012). Influence of natural fibres chemical modifications on flammability of polyurethane composites. 18(3), pp. 189–193.

[12] H. Al-Hamaiedeh, M. Bino, (2010). Effect of Treated Grey Water Reuse in Irrigation on Soil and Plants, Desalination, 256, pp.115 – 119.

[13] Thirugnanasambandham, K. et al., (2014), Chitosan based greywastewater treatment: A statistical Design Approach. Carbohydrate Polymers, 99, pp.593 – 600.

[14] N.M. Julkapli, H.M. Akil (2008). Degradability of kenaf dust-filled chitosan biocomposites. Materials Science and Engineering, C28, pp.1100–1111.

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