*3.1.4 Malvern Mastersizer*

Particle size distribution (PSD) of feed materials and carbonated products were determined using a particle size analyser (Mastersizer 2000, Malvern Instruments) (**Figure 11**). For particle size measurement, it is important how particles scatter and absorb light. Initially, the Fraunhofer model [36] was used to predict scattering patterns when a solid disc of particles is passed through the laser beam. This model failed to describe exact scattering as very few particles are disc-shaped. Mie theory is currently used which is able to predict the light scattering behaviour of all materials. Each size of particle has a specific scattering pattern. The particle size analyser uses the above-mentioned theories and works backwards to calculate particle

**Figure 9.** *Block diagram of FTIR spectrometer.*

### **Figure 10.**

*Typical FTIR spectra of raw dunite, stretch present around 3690 cm<sup>1</sup> are due to presence of surface-bound OH moieties, the vibration at 1073 cm<sup>1</sup> due to out of plane vibration of Si-O, adsorption band at 970 cm<sup>1</sup> are inplane Si-O stretching vibration, the feature at 629 cm<sup>1</sup> are due to deformation of hydroxyl groups, stretches at 564 cm<sup>1</sup> are Mg-O out of plane vibration, stretches at 450 cm<sup>1</sup> are Si-O-Si bond bending vibration (reference [9] and references therein).*

size from the captured scattering pattern. Basic laser diffraction system is shown in **Figure 12**.

Three procedures are used for any particle size measurement. First, a sample is prepared and dispersed in a dispersion unit in proper concentration followed by its delivery to the optical bench. Second, a scattering pattern is captured from this sample which is also called "measurement" and is done by the optical bench. Third, raw data from measurement is analysed by instrument software to provide the PSD. Finely ground samples (≤20 μm) were preferably analysed in wet solution form. These samples tend to agglomerate during drying even if dried under vacuum and at low

*Testing and Validating Instruments for Feedstocks of Mineral Carbonation DOI: http://dx.doi.org/10.5772/intechopen.101175*

### **Figure 11.**

*Photo of Malvern mastersizer 2000. A: Sample dispersion unit and pump impeller, B: Sample cell where dispersed sample is moving and laser light pass through it, C: Laser source and laser ON indicator, D: Pump speed adjustment and ultrasound operation system, E: Computer to show output.*

### **Figure 12.**

*Basic laser diffraction system of Mastersizer 2000.*

temperatures (70°C). For these samples and heat-activated samples, a built-in ultrasonic system in the Malvern mastersizer was used to break any agglomerates present. A typical PSD from the Malvern mastersizer is shown in **Figure 13**. Size classes are represented on the x-axis in μm and the volume density of particles is represented in percentage on the y-axis. The percentiles, d10, d50 and d90 are shown in **Table 3**. D10 means that 10% volume of particles is smaller than this size (27 μm), d50 means that 50% volume of particles is smaller than this size (42 μm) and d90 means that 90% volume of particles is smaller than this size (64 μm).

## **4. Results and discussion**

Olivine (Netherland) and Olivine (Norway) characterisation using Quantitative XRD (X-Ray Diffraction) analysis is discussed. The supplier of these samples has promised to supply olivine; however, these appear as a mixture of olivine and a few other minerals. These samples may be rocks but still, Olivine (Norway) is probably like olivine as it has higher olivine content. This olivine content (62%) almost match lizardite content (61–62%) of the dunite [18] used primarily in my research.

### **Figure 13.**

*PSD for 20–45 μm dunite (left), PSD for 20–45 μm olivine (right).*


### **Table 3.**

*PSD for 20–45 μm dunite and 20–45 μm olivine.*


### **Table 4.**

*Olivine (Norway) and olivine (Netherland) QXRD analysis.*

Powders samples were prepared for QXRD analysis of olivine (Netherland) and olivine (Norway). **Table 4** shows the analysis. Please refer to earlier publications [2, 10, 13, 14, 18, 19] for detailed description of methods. TGA-MS curves are presented in **Figure 14**. TGA commonly used in mineral carbonation to obtain yields was coupled with MS (Mass Spectrometer). This enabled us to calculate yields for dunite rock as evolved CO2 gas and water vapours were measurable. TGA-MS was routinely calibrated. One example of calibration curves is shown in **Figure 15**.
