Tecnura (Jun 2011)
Modificación estructural de la lignina extraída a partir de carbones de bajo rango para la obtención de madera sintética
Abstract
The Universidad Distrital Francisco José de Caldas Coal Research Group has been working with lignin extraction from peat and low rank coal and using the obtained extract for synthetic wood industry. Sosa, sulfate and bisulfite methods [1] were applied in the first research step and later they were modified with the lignine extraction process from pine and cedar. Among these, Sosa method showed asthe more efficient method, so, it was used to extract lignine from low rank coal. The extracted lignin was used to prepare lignin-phenol-formaldehide resin and it works as natural fiber binder [2].In the second research step, standarization Sosa method was made [3], were pressure was modified using an pressure reactor (autoclave) for a peat sample. Efficiency was improved. The obtained lignine was used to prepare resins such as phenolformaldehide- lignin, resorcinol-formaldehydelignin and polypropilen-lignin. All of them were utilized using sugar cane bagasse as natural fiber. Currently, a third research step is being developed using Sosa method and working with a peat sample.The main purpose, is to modificate the extracted lignin structure by UV radiation (physical methot) and with NaOH (Chemical method) so the lignin reactivity is improved in the resins production [4] and as result, to get a better quality synthetic wood.