| dc.description.abstract | Wood physical product such as plywood and the particle board yielded without chemical process, whereas natural wood product with chemical process it’s pulp. In general pulp known as the raw material maker of paper, but it doesn’t always made the material maker of paper. Pulp can be made to be like writing paper, newspaper, newsprint, aglutinant, and or cloth fibre for the clothes. Requirement pulp domestic still very large. In the year 2004 requirement of import pulp equal to 850.000 ton (pulp NBKP - Northern Bleached Kraft Pulp) and 50.000 ton (non wood pulp) for the price of US$ 418.500.000 (Sudjindro, 2007) Process of making the chemical pulp is the higest cost compared to the making mechanical pulp or the semimechanical pulp. One of costly cause of chemical pulp is the yield which is low to be compared to semichemical pulp an or mechanical pulp, but process of chemical pulp yield the paper product is higher in quality compared to mechanical process or semichemical. In making chemical pulp some active materials composition is needed so pulp can reach the optimal result according to requrement. Costly chemical material cost and quality of pulp is a factor influence the price of the pulp, so we need to find the best combination from both factor. One of the natural wood type in Indonesia were able to be used as raw material for chemical pulp is Jati Putih (Gmelina arborea) which has characteristic to relatively vast growth. Exploiting of this wood is more beneficial used as the raw material of chemical pulp compared to be a tool. At this research relation between yield values and cost factor chemical pulp material (konsentration of active material and pH) used as determinant factor of optimal production cost of chemical pulp of Jati Putih materials (Gmelina arborea). This research aim were to know relation between pH, alkali consentration, and combination both to expense process pulping and also know the combination pH alkali consentration which give the best (lowest) production cost. This researches scope cover pulping process or making pulp by chemical process with pH 5 to 9 using the alkali consentration 16% and 18% in condition comparation of solid to water is one compared to four. Result of ANOVA test indicate that treatment with pH and active alkali consentration have an effect sgnificantly to yield pulp values, but interaction among them don’t have an significant effect. Best treatment combination between pH and alkali consentration is obtained at pH 7 and active alkali concentration 16%. This conbination give the lowest average cost | id |
