**2.4 Jar test**

Each beaker in jar test was filled with 500 mL of wastewater sample. 10 mL of *Moringa oleifera* press cake with different concentrations prepared were added into each beaker. The stirring speed was set at 200 rpm for 4 min followed by 40 rpm for 30 min [35].

### **2.5 Atomic absorption spectrometer**

Atomic absorption spectrometer (AAnalyst 400, Perkin Elmer) was used to measure initial and residual heavy metal in treated water. Stock solution prepared from each standard at different concentrations was used to get calibration curve for

**267**

**Table 1.**

*Heavy metal removal from Gebeng River, Kuantan, Malaysia.*

*Removal of Heavy Metals from Water and Wastewater Using* Moringa oleifera

each metal [30]. Wavelength of 324.80 nm was used to measure the Cu(II) concentration and 228.8 nm for Cd(II) measurement using an acetylene air flame [10, 31].

The stock solution was prepared by adding the distilled water to *Moringa oleifera* cake residue and forming a paste at different concentrations of 10,000, 20,000, and 30,000 mg/L by dissolving 50, 100, and 150 mg of the seed powder in 5 ml distilled

The water samples of the Cu(II), Cd(II), Fe(II), Pb(II), and Cr(II) study were

collected from "Sungai Baluk" river (Gebeng River {GR}), Gebeng Industrial

The synthetic water was prepared for measuring Cd(II) removal [10].

The heavy metals of Cu, Cd, Fe, and Pb were high in the GR water samples. After a tenfold dilution, the concentration of these metals is still more than 1 mg/L. *Moringa oleifera* cake residue showed that iron (Fe) was fully removed, while copper (Cu) and cadmium (Cd) were successfully removed up to 98%. The reduction of lead (Pb) by 82.31% was achieved (**Table 1**). The initial amount of Fe was 1.306 mg/L and fully removed by *Moringa oleifera* cake residue. This result was totally agreed with [4] study, while [37] had reported that a reduction of Fe by using *Moringa oleifera* cake residue was up to 92% if compared to other heavy metals. Fe was fully removed, and the level of Fe achieved the water standards since concentration of Fe in water should be less than 0.30 mg/L (National Water Quality Standard from Malaysia). In this study, the removal of Pb was within the range of the previous research [37, 38] which indicated that Pb can be removed within 80–89% by using *Moringa oleifera* seed if compared to other natural sources such as beans and peanuts. Copper removal was better than [38] results of Cu which was 90%. The results of Cd removal were in contrast with [37] since the latter results showed 48% of Cd was removed which might be due to the absence of oil extraction from seeds. In a different study, it was found in Balok River wastewater, Gebeng, Kuantan, that the concentration of Fe and Cr metal were 1 mg/L, while Cu concentration was 0.4 mg/L. *Moringa oleifera* solution was added into the wastewater with different doses to determine the optimum dose. The heavy metals were successfully reduced after the treatment with the *Moringa oleifera* press cake. The removal percentage of iron, copper, and chromium reached 69.99, 88.86, and 93.73%, respectively

*DOI: http://dx.doi.org/10.5772/intechopen.89769*

**2.6** *Moringa oleifera* **solution preparation**

water to obtain 1, 2, and 3%, respectively [36].

Estate, Kuantan, Pahang State, Malaysia [30].

**2.7 Water samples**

**3. Results**

each metal [30]. Wavelength of 324.80 nm was used to measure the Cu(II) concentration and 228.8 nm for Cd(II) measurement using an acetylene air flame [10, 31].
