African oil palm, Elaeis guineensis, is one of the most important plants in Malaysia. It produces palm oil and palm kernel oil, which are widely used in food and other industries such as detergents and cosmetics. Malaysia is the world's largest producer and exporter of the oil, accounting for approximately 10% of the world's oil and fat production (1998). The total area of oil palm plantations is close to 3.2 million hectares, which account for almost 50% of the land under cultivation in Malaysia.

Although oil from the palm tree is an excellent product for the country, residues from oil palm have not been used sufficiently. One of the abundant lignocellulosic residues consists of empty fruit bunches (EFB), which are left behind after removal of oil palm fruits for the oil refining process at palm oil refineries. Tons of EFB are discharged from each refinery regularly, amounting to 16 million tons per annum in the year 2000. Some of them are used as fuel at the factories, but most of them are left unused.

Converting this lignocellulosic waste to paper-making pulp is a promising way of utilization, as the consumption of paper is increasing dramatically in the Southeast Asian countries including Malaysia. Several investigations have been carried out on EFB pulping, whereas studies on bleaching of EFB pulp have been very limited so far. Collaboration work between JIRCAS and Universiti Sains Malaysia (USM) has, therefore, focused on the bleaching of chemical pulp from EFB, especially using total chlorine-free (TCF) methods.

TCF bleaching was examined for EFB chemical pulps such as kraft, soda and soda-anthraquinone pulps. TCF processes include oxygen (O₂) delignification, ozone (O₃) bleaching, acid treatment, hydrogen peroxide (H₂O₂) bleaching and alkali extraction. It was found that a pulp brightness of 75% can be obtained for EFB kraft pulp by a bleaching sequence of O₂-acid-O₃-H₂O₂. The brightness is required to be above 80% for commercial bleached kraft pulp based on JIS Standard. Mechanical properties such as tensile and tear strength of handsheets produced from this pulp were found to be comparable to those of hardwood pulps. Furthermore, since the TCF bleaching method removes most of the coloring compounds, that is lignin, in EFB, the bleaching ability is assumed to be similar to that of bleaching methods using chlorine. Soda pulp and soda-anthraquinone pulp of EFB, which contain less lignin than EFB kraft pulp, have also reached a brightness level of 70-75% with a single bleaching stage using O₂ or O₃. This also indicates that the coloring materials in EFB can be easily removed without using any chlorine compounds.

Based on this study, we observed that the total chlorine-free bleaching method can be applied to EFB chemical pulps and that EFB is suitable as a raw material of chemical pulp. Although the bleaching and even pulping methods for producing EFB pulp for paper-making have not been optimized yet, there is a great potential for the utilization of this oil palm lignocellulosic residue in pulp and paper industries. Currently, the world trend in pulp bleaching is toward the application of non-chlorine processes because of environmental concern. Once the oil palm by-product becomes a raw material for pulp production, it will be essential to develop TCF bleaching processes in future.