Resource recovery and reduction of tidal waste through clean processes to obtain cellulose

Abstract

The transition towards a sustainable cellulose industry needs more environmentally friendly technologies that include the use of less polluting processes and alternative raw materials. This work shows the potential of tidal waste from the Andalusian Mediterranean coastline as cellulosic material to obtain cellulosic pulp. With this purpose, predominant species in onshore residues (mainly Posidonia oceanica) were prepared, characterized, and subjected to a soda-anthraquinone pulping process. A central composite design was defined in order to relate the process conditions to the composition and characteristics of the cellulose pulp. It was concluded that polynomial models encompassing linear, quadratic, and binary effect parameters reproduce the experimental results satisfactorily. Results allowed to choose high anthraquinone concentration, soda concentration and temperature (1%, 30% and 150 ºC, respectively), low liquid/solid ratio (4) and short time (30 min) as a compromise solution, by which the brightness, ethanol-benzene extractives content, kappa index, lignin content and viscosity were near their optimal. Low values of liquid/solid ratio reduce water consumption, which is of utmost importance in cellulose industries likewise short time treatments to saves energy.