**1. Introduction**

The rapid development of the textile industry has resulted to a large proportion of industrial wastewater pollution. Methylene blue (MB) dye is a most widely used dye by industries like textile, paper, rubber, plastics, leather, cosmetics, food industries and pharmaceuticals. The textile industry is classified into three main categories, namely; cellulose fibers (cotton, rayon, linen, ramie, hemp and lyocell), protein fibers (wool, angora, mohair, cashmere and silk) and synthetic fibers (polyester, nylon, spandex, acetate, acrylic, ingeo and polypropylene) [1]. The type of dyes and chemicals used in the textile industry are found to differ depending on the fabrics manufactured. Reactive dyes (remazol, procion MX and cibacron F), direct dyes (congo red, direct yellow 50 and direct brown 116), naphthol dyes (fast yellow GC, fast scarlet R and fast blue B) and indigo dyes (indigo white, tyrian purple and indigo carmine) are some of the dyes used to dye cellulose fibers [1]. The textile industry is known to be the main creator of wastewater effluents because it

consumes more water for its wet processes. Therefore, globally it is estimated that all wastewater discharge is highly populated. According to the world bank estimation, textile dyeing and finishing treatment given to a fabric generates at least 17– 20% of world's industrial wastewater [2, 3].

**2.2 Methods**

10, 20, 30, and 40 cm<sup>3</sup>

*2.2.1 Synthesis of pine-magnetite composites*

*DOI: http://dx.doi.org/10.5772/intechopen.92114*

*2.2.2 Synthesis of grafted pine magnetite composite*

was dried in a vacuum oven at 40°C.

Elmer) in the range 450–4000 cm<sup>1</sup>

**2.3 Characterization**

netite (Fe3O4 PMC).

**159**

**3. Results and discussions**

**3.1 FT-IR spectroscopy results**

A mixture of FeSO47H2O (2.1 g) and of Fe(SO4)3XH2O (3.1 g) were dissolved under inert atmosphere in 100 cm3 of double-distilled water with vigorous stirring. Thereafter, 20 cm<sup>3</sup> of 28% ammonium hydroxide and the appropriate amount of pine powder was added. The reaction was left to run for 45 min at 80°C under constant stirring. The resulting particles, consisting of magnetite attached to the cellulose (hereafter referred to as bio-composite) were washed several times with deionized water and ethanol and dried in a vacuum oven at 60°C overnight. To

*Characterization of Grafted Acrylamide onto Pine Magnetite Composite for the Removal…*

determine the optimum conditions to achieve the desired products of the

temperatures 40, 60, 80 and 100°C and reaction times 15, 30, 45 and 60 min.

of deionised water were transferred into a three neck round bottom flask at a temperature of 42°C. The reaction was bubbled under nitrogen gas for 30 min to remove the dissolved oxygen under stirring. 10 ml of 0.5 M CAN, dissolved in 0.3 M HNO3 was slowly added to the reaction to initiate graft co-polymerization and stirring was continued for 2 h. Reaction mass was neutralised by 50% NaOH and precipitated in methanol and thereafter washed with methanol/water (90:10) several times, so that the unreacted PMC and ceric salt were removed. The final residue

biocomposites, we experimented with the following variables: volume of NH4OH 5,

1 g of pine magnetite composite (PMC), 20 ml of 1.5 M acrylicamide and 135 ml

Qualitative and fundamental identification of the functional chemical groups of grafted pine magnetite composite (GPMC) were carried out with a FTIR (Perkin-

analytical, PW3040/60 XRD; CuKα anode; *λ* = 0.154 nm) was used for particle size measurements. The size of the synthesized particles was observed using transmission electron microscope (TEM, FEI TECNAI G<sup>2</sup> SPIRIT) at an accelerating voltage of 150 kV. TGA (Perkin-Elmer (USA) Simultaneous Thermal Analyzer 6000 instrument) was used for determining the weight loss as a function of temperature. Changes in morphology were studied using scanning electron microscopy (SEM), HRSEM Instrument Specs Model: Jeol JSM 7800F field emission scanning electron microscope run operational voltage: 5kVEDS specs Model: Thermo Fischer UltraDry EDS Detector for the graft co-polymerization and incorporation of iron oxide mag-

The FT-IR spectrum shown in **Figure 1(a)** represents the pine-Fe3O4 magnetite (PMC). The FT-IR spectrum showed some changes in band intensities, indicating the functional groups on the surface that had been modified. A compressed dOH peak at 3350 cm<sup>1</sup> with an increase in intensity was observed. This might have been

. An X'Pert PRO X-ray diffractometer (PAN

; weight of pine powder 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5 g;

Dyes often discharged in water effluents contain residues that are highly visible and undesirable even at low concentrations [4]. In addition, they are toxic due to their harmful effects on the human beings. Therefore, it is of vital importance that they are removed from water [5]. Wastewater containing dyes needs to be treated before being discharged into water bodies [6]. Various techniques including chemical oxidation, coagulation-flocculation, membrane processes and biological treatment have shown effectiveness in the removal of methylene blue from waste water [7]. The limitation most of these techniques possess is the incomplete dye removal, poor detection, requirement of expensive equipment and monitoring systems [6]. The performance of adsorption techniques have been applied due to their effectiveness since they remove the entire dye molecule, leaving no fragments in the effluent [8].

Extensive research in recent years has focused on utilizing waste materials from agricultural products (such as pine cones and others) since they are eco-friendly, cost-effective and renewable [9]. Pine cones are naturally occurring agricultural wastes widely found in a plantation in Vanderbijlpark, Gauteng, South Africa. They are of commercial importance and value which is extensively used in different industries [10]. One pine cone consists of 46.5% hemicellulose, 37.4% lignin, 18.8% cellulose and 15.4% extractives [11]. Pine cone powder has been studied extensively in the removal of heavy metal pollutants such as lead, caesium, copper nickel and arsenic from water systems. Activated carbon has been the most employed adsorbent for the removal of dyes due to its outstanding adsorption properties. However, it has limitations by being expensive and it cannot be used in large applications of wastewater treatment. The use of biomass and other microbial cultures in the removal of methylene blue has been extensively studied in recent years. Among others, carbonized organic materials, fly ashes, peat moss, recycled alum sludge, fishery residues and microorganisms such as fungus and algae [12].

The present study reports the development and characterization of grafted pine magnetite composite using grafted acrylamide (GACA) for the removal of methylene blue in wastewater. Grafting is a process of chemically or physically manipulating the surface properties of plant materials such as type and amount of functional groups, surface area and porosity by extraction of plant chemical components in order to improve its adsorptive ability. Grafting of synthetic monomers onto pure biological materials has been successfully performed, e.g., grafting of acrylonitrile onto starch [13] and methyl acrylonitrile onto cotton [14].
