Utilization of Stone Cutting Waste in Production of Calcium Stearate
Publication Type
Original research
Authors

Stone cutting waste (SCW) which contains large amounts of calcium carbonates (CaCO3) was converted to calcium stearate (C36H70CaO4) by two methods; First: converting SCW into calcium chloride (CaCl2) by reacting it with excess hydrochloric acid (HCl) then the produced CaCl2 was reacted with sodium soap (sodium stearate; C18H35NaO2) prepared from used cooking oil, the soap was dissolved in water at 60 ºC, while in the second method the produced CaCl2 was reacted with sodium hydroxide (NaOH) to produce calcium hydroxide Ca(OH)2 which then reacted with oil to produce calcium stearate, the former reaction took place at 150 ºC. Some tests were carried out; PH, solubility, ash and DSC test to examine the properties of the produced calcium stearate, it was found that the sample prepared from reacting 250g of SCW with 333 ml HCl (15 wt.%) and reacted with 0.5 Kg of sodium soap dissolved in 1 liter water at 60 ºC had the following properties; it is a hard powder, insoluble in water, with melting temp 129.87 ºC and softening temp 73.92 ºC, the ash content was 21% and with a PH equal 6.5. The aforementioned sample costs about 0.53 $/kg compared with 1.2 $/kg for imported calcium stearate. Produced calcium stearate could be used in different applications; wire drawing lubricant or as thickening agent in preparation of lubricant calcium greases in addition to other industrial applications such as paper, PVC, cement and in personal care and pharmaceutical industry include tablet mold release, anti-tack agent, and gelling agent.

Journal
Title
International Journal for Environment& Global ClimateChange
Publisher
The Euro-Arab Organization for Environment, water and desert research
Publisher Country
United Kingdom
Publication Type
Both (Printed and Online)
Volume
5
Year
2017
Pages
28-36