What is Organosolv pulping?
Organosolv pulping is a two-stage process involving hydrolysis (decomposition of wood by use of a catalyst) and removal of lignin with an organic solvent (usually a mixture of alcohol and water).
What is Organosolv pretreatment?
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.
What is kraft lignin?
Kraft lignin is a kind of industrial lignin obtained from Kraft pulp, which accounts for about 85% of the total lignin production in the world. The Kraft pulp method is the main method for converting coniferous wood to pulp; the pulping yield is higher than other alkaline pulping methods.
What is soda lignin?
Soda lignin is made from the soda pulping process. Compared to Kraft lignin and lignosulfonates, soda lignin is sulfur-free and has higher purity. 89,97,98. The soda pulping method is mainly used for processing annual crops such as straws, bagasse, and hardwood.
What is solvent pulping?
Solvents. Organosolv pulping involves contacting a lignocellulosic feedstock such as chipped wood with an aqueous organic solvent at temperatures ranging from 140 to 220 °C. The concentration of solvent in water ranges from 40 to 80%. Higher boiling solvents have the advantage of a lower process pressure.
What is Kappa in pulp?
The Kappa number is a measure of the degree of fibrous pulp digestion and can be applied to determine lignin content [44–46]. Its value can vary from 0 for practically lignin-free wood pulp (bleached wood pulp) to approximately 60 (standard unbleached wood pulp) [47].
What is kraft process in paper making?
The kraft process (also known as kraft pulping or sulfate process) is a process for conversion of wood into wood pulp, which consists of almost pure cellulose fibers, the main component of paper. It is the dominant method for producing paper.
What is NSSC pulp?
NSSC (Neutral Sulfite Semi Chemical) pulping is a type of semi-chemical pulping process to produce unbleached pulp at yields of around 80%. Hardwoods are normally used as raw material and the produced pulp is mainly used for production of corrugating medium (fluting).
What is Sulfidity in soda pulping?
This innovation originated what is currently known as “kraft” or “sulfate” pulping process. The sulfate denomination is because of the addition of sodium sulfate (Na2SO4) in the chemical recovery plant that is also called “salt cake” and is used as a make-up to replace chemical losses.
What is lignin in paper?
A complex, organic material in wood that binds fibers of cellulose together. It is the presence of lignin in paper pulp that reduces paper permanence and contributes to the yellowing of paper over time. …
In industrial paper-making processes, organosolv is a pulping technique that uses an organic solvent to solubilise lignin and hemicellulose. It has been considered in the context of both pulp and paper manufacture and biorefining for subsequent conversion of cellulose to fuel ethanol.
How do you make organosolv lignins?
Additionally, Organosolv lignins can be obtained using organic solvents such as alcohols, glycols, phenols, esters, organic acids, acetone, and amines [51]. The main advantage of these processes, in comparison with the abovementioned pulping processes, is the production of a lignin whose chemical structure is very similar to native lignin.
What is the tensile and tear strength of softwood organosolv pulps?
Tensile and tear strengths of softwood organosolv pulps fall between the corresponding values of Kraft and sulphite pulps. The published data shows that organosolv pulping methods have considerable potential in terms of delignification selectivity and papermaking quality.
What are the advantages of organosolv?
Organosolv has several advantages when compared to other popular methods such as kraft or sulfite pulping. In particular, the ability to obtain relatively high quality lignin adds value to a process stream otherwise considered as waste.