Open AccessRecycling of residual liquids from the conversion of calcium alginate to alginic acid during alginate production process.
Author(s) -
Y. Elizabeth Rodríguez-Montesinos,
Gustavo HernándezCarmona,
D.L. Arvizu-Higuera
Publication year - 2005
Publication title -
cicimar oceánides
Language(s) - English
Resource type - Journals
eISSN - 2448-9123
pISSN - 1870-0713
DOI - 10.37543/oceanides.v20i1-2.17
Subject(s) - alginic acid , calcium alginate , calcium , chemistry , yield (engineering) , glucuronic acid , chemical engineering , chromatography , pulp and paper industry , materials science , biochemistry , organic chemistry , polysaccharide , composite material , engineering
The effect of recycling the residual acid solution from the conversion of calcium alginate to alginic acid from the alga Macrocystis pyrifera was studied. The residual liquid was recycled using a countercurrent system; it was possible to treat three batches of calcium alginate with the same amount of water, with an effective conversion into alginic acid, saving 56% of fresh water. An in line recycling system was experimented (without water replacement). This system is not recommended, because the large increase of calcium in the alginate after the second recycling, produces a very high apparent viscosity. Using this system the viscosity was reduced in more than 50%. We experimented the effect of the number of acidwashings of the alginic acid, on the yield and quality of the final alginate. The acid treatment was carried outwith three, two and one washing. It was concluded that three acid washings of the calcium alginate fibers arenecessary to obtain an effective conversion of calcium alginate to alginic acid, but the first and second washings can be carried out with recycled acid. This system represents a water saving up to 66% in this step.