Abstract:
Recycle is known as the process of converting waste materials into new product that
potentially useful. In this project, new soap is produced from disposed hotel bar soap to
reduce the waste from hotel. Water content, glycerin content, and salt content are the
parameters studied in this recycling process. Moisture content was analyzed as the main
characteristic of soaps. The Response Surface Methodology (RSM) approach was applied
to get the optimum condition for the parameters to produce soap within the moisture
content allowable range which is 15%-30%. Only 3 out of 20 experiments produced out-ofrange
moisture content which is experiment number 11, 5.09%, number 5, 38.32%, and
number 14, 35.27%. The most important reasons are glycerin content and salt content
which has the p-value of 0.0096 and 0.0116 respectively. Those values indicate that
glycerin and salt content are the parameters which are significant. The techno-economic
study revealed for a bar soap of 100 grams, the production cost is RM 1.70. It was
concluded that the production of new soap from disposed bar soap was successfully
accomplished by optimizing the three parameters. The result on techno-economic study
indicates that it is necessary for future study to constrict the production cost of soap, so that
the production will be less costly.
