Paper degradation rosin

Separation of fatty acids (Ruthven, 1997). Tall oil from the pulp and paper industry is subjected to separation of rosin acid, linoleic acid, oleic acid, and neutral compounds. Distillation at reduced pressure is u.sed, but this leads to degradation of products. A Sorbex process eliminates this problem. 

The important point is that the cellulose in these alum/rosin sized papers is susceptible to acid hydrolysis, which results in a lowering of the degree of polymerisation and, eventually, to a serious reduction in the strength of fibres and to complete embrittlement of the paper. Some recent work in the writer s laboratory suggests that when alum/rosin papers are made, the hydroxonium ions which lead to the degradation are adsorbed independently of aluminium ionic species (4). 

One of the most industrially important characteristics of papers is their chemical stability, which enables them to withstand degradation with its consequential loss of tensile and tear strength and fold endurance under normal conditions of use. However, this stability is not absolute. Cellulose is susceptible to oxidation and the glycosidic linkage is susceptible to hydrolysis. In order to protect book papers from acid degradation, they must not be exposed to acid. Acids are generated from the alum-rosin size as well as from such... 

Separation of Fatty Acids. Tall oil is a by-product of the pulp and paper manufacturing process and contains a spectrum of fatty acids, such as palmitic, stearic, oleic, and linoleic acids, and rosin acids, such as abietic acid. The conventional refining process to recover these fatty acids involves intensive distillation under vacuum. This process does not yield high purity fatty acids, and moreover, a significant degradation of fatty acids occurs because of the high process temperatures. These fatty and rosin acids can be separated using a UOP Sorbex process ( 93—99) (Tables 8 and 9). 

The production of pulp and paper delivers by-products that can principally be recovered and utiHzed as renewable raw materials. The waste liquor of alkahne pulping, the so-caUed black Hquor contains inter alia acetates, degradation products, soluble alkali Hgnin as well as saponified rosin acids and fatty acids. Black liquor can be combusted to provide energy for the plant or alternatively yield crude tail oil (CTO) which contains between 15 and 55% fatty acids and 20-65% rosin aids [15]. World production of CTO can be estimated to be about 1.5 miUion tons [41]. 

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