In this study carbide lime waste was used as raw material to produce precipitated calcium carbonate (PCC). Carbide
lime is an industrial waste from acetylene gas industry which uses limestone in its production. The use of PCC as fillers
in paper making can reduce the production cost and improve the paper properties such as opacity and brightness. PCC
can be produced from carbide lime waste by ionic sucrose solution method. The sucrose solution of Brix 10° was first
prepared by dissolving sugar (sucrose) in water followed by dissolution of carbide lime waste in the sucrose solution.
The sucrose solution which had turned milky was then filtered to obtain a clear solution known as pregnant solution.
The pregnant solution that contained calcium ions was subsequently used to produce PCC by introducing CO2
gas into
the pregnant solution. The process is known as carbonation. The PCC was then used as fillers in paper making. The
production of PCC by using calcium hydroxide as starting material was also carried out for comparison purposes. Based
on the results, PCC prepared from carbide lime had purity of 98.14% while the one prepared from calcium hydroxide had
98.66%. Meanwhile, analysis of the paper properties demonstrated that both products gave equally good results. This
proves that PCC prepared from industrial waste can be used for paper making.
Precipitated calcium carbonate fillers were loaded into the lumen of bleached mixed tropical hardwood pulp using polyethylenimine (PEI) and alum. Our results indicated that the addition of (PEI) increased the degree of loading of precipitated calcium carbonate (PCC) into the lumen of fibers. The degree of loading also increased with the addition of alum together with PEI. The mechanical strengths of the produced lumen loaded paper increased with the addition of PEI and alum. Meanwhile the mechanical strength without alum had slightly increased the mechanical strengths of the paper. Electron micrographs revealed that the PCC fillers were successfully loaded into the lumen of the fibers.