EXPERIMENT TITLE: Partial Oxidative Roasting of Hematite

AIM: To determine the the effect of partial oxidative roasting on percentage composition of haematite $($Fe$2$O$3)$

OBJECTIVES:

$$ To study the decomposition kinetics of hematite $($Fe$2$O$3)$ during partial roasting through quantification of weight loss at increasing temperatures over time.

$$ Determining the optimal roasting temperature

$$ Investigating the effect of temperature on roasting

$$ Evaluate the efficiency of the roasting process

$$ Analyzing the properties of the roasted sample

THEORY:

Partial oxidative roasting is a metallurgical process that involves heating a sulfide ore in the presence of air at high temperatures. The objective of this process is to convert the sulfide ore into its oxide form, which can then be further processed to extract the desired metal.

During partial oxidative roasting, the sulfide ore undergoes a chemical reaction with oxygen from the air. This reaction results in the conversion of the sulfide minerals into their corresponding oxide minerals. The oxygen from the air combines with the sulfur in the sulfide ore to form sulfur dioxide $($SO$2)$ gas, which is released. At the same time, the metal component of the sulfide ore is oxidized to its oxide form.

The specific objectives of partial oxidative roasting can vary depending on the context and the desired outcome of the study. Some common objectives include:

Conversion of sulfide minerals to oxide minerals: The primary objective is to convert the sulfide minerals present in the ore into their corresponding oxide minerals. This conversion is important because oxide minerals are often more amenable to subsequent processing steps for metal extraction.

Enhancement of metal recovery: Partial oxidative roasting can improve the recovery of metals from the ore. By converting the sulfide minerals to oxide form, the subsequent extraction processes can be more efficient and effective in recovering the desired metal.

Reduction of impurities: The roasting process can also help in reducing impurities present in the ore. Some impurities may be volatile and can be removed as gases during the roasting process. This can result in a purer final product.

Optimization of process variables: Another objective of partial oxidative roasting experiments is to investigate the effects of various process variables such as temperature, time, and gas composition on the roasting efficiency and the quality of the final product. By studying the influence of these variables, researchers can optimize the roasting conditions to achieve the desired outcomes.

APPARATUS :

Muffle furnace

Zirconium crucible

Mass balance

Pulverizer

$75$ micron sieve

Spatula

Tong

Heat resistant suit

PROCEDURE:

$1.$Perform an elemental analysis on your ore sample using XRF machine

$2.$Crush and grind your sample to $80\%$ passing $75$ microns

$3.$ Weigh $5$g of ground hematite ore sample into a zirconium crucible.

$4.$ Place the crucible into a muffle furnace heated to $800\backslash$deg C

$5.$Periodically open the furnace door to allow air into the furnace to facilitate the oxidation

$6.$ Use a stopwatch to set a timer for $5$ minutes

$7.$ Remove the crucible after the $5$ minutes have lapsed

$8.$Allow the crucible to cool

$9.$Weigh the sample using a mass balance

$10.$ Repeat the procedure varying the time from $10$ minutes to $15,$with a $5$ minute increase in time till there is no change in weight of the sample with an increase in temperature

$11.$Prepare a sample of the roasted ore for elemental analysis by an XRF machine

SPECIMEN DETAILS BEFORE ROASTING

ID Group $1$

App. QuantExpress$\backslash$Oxides

Type Routine measurement

Priority Priority: Normal

Start $3/25/202410$:$29$:$01$ AM

End $3/25/202410$:$35$:$31$ AM

Completed in $0$:$06$:$30$

Material Oxides

Mode Vac

Diameter $34$mm

Method Full Analysis$-$Vac$34$mm

SiO$240\mathrm{.}8\%$

Fe$2$O$38\mathrm{.}96\%$

Al$2$O$310\mathrm{.}3\%$

SO$30\mathrm{.}165\%$

Bi$2$O$30\mathrm{.}112\%$

K$2$O $2\mathrm{.}62\%$

MnO $0\mathrm{.}159\%$

Na$2$O $0\mathrm{.}389\%$

TiO$20\mathrm{.}385\%$

MgO $0\mathrm{.}114\%$

P$2$O$5430$PPM

ZrO$2187$PPM

ZnO $106$PPM

SrO $86\mathrm{.}5$ PPM

CaO $538$ PPM

MoO$3439$ PPM

Cr$2$O$3253$ PPM

CuO $101$PPM

Fig $1\mathrm{.}0$ :sample ore before roasting

Fig $2\mathrm{.}0$ :Sample ore after roasting

SPECIMEN DETAILS AFTER ROASTING

ID Group $1$

App. QuantExpress$\backslash$Oxides

Type Routine measurement

Priority Priority: Normal

Start $3/25/202410$:$29$:$01$ AM

End $3/25/202410$:$35$:$31$ AM

Completed in $0$:$06$:$30$

Material Oxides

Mode Vac

Diameter $34$mm

Method Full Analysis$-$Vac$34$mm

SiO$253\mathrm{.}2\%$

Fe$2$O$37\mathrm{.}44\%$

Al$2$O$30\mathrm{.}271\%$

SO$30\mathrm{.}165\%$

Bi$2$O$30\mathrm{.}112\%$

K$2$O $943$ PPM

Cr$2$O$3509$ PPM

MoO$3439$ PPM

CaO $1$ PPM

CuO $101$ PPM

MnO $61\mathrm{.}8$ PPM

WHAT ARE REACTIONS THAT OCCUR DURING ROASTING THAT INVOLVE HAEMATITE FROM THE ABOVE EXPERIMENT