First step in the project has been to identify and select potential micro- and macroalgae strains/species that can be used a raw material for the dye industry.
Specific criteria for selection are:
- Availability: Culture collection
- Growth characteristics: growth rate (μ); duplication times (td) and production yield
- Pigments composition (target pigment)
- Stages for metabolite synthesis (one vs two phases; stress conditions)
- Dye yields: production yield “product of interest” content
- Possibilities for cultivation at industrial scale (considering processing techniques)
- Strain Improvement: pigment accumulation under cultivation conditions.
Second step has been the biomass production under controlled conditions for growth and composition characterization (target pigment concentration; purity criteria; stability, etc).
Next step will be testing these pigments/dyes in dyeing process; therefore it is necessary to study the pigment extraction process.
Determination of the inorganic salts concentration in the process will be necessary to evaluate the colour fastness. Accordingly, the efficiency of the color protection will be studied.
Due to the fact that in this Project, macro algae and microalgae, are used for pigment extraction, below will be presented the corresponding processes.
The procedures will be separated according to the state of the algae: fresh or dry biomass. All the extractions require a mechanical cell rupture, which include the usage of a specific solvent for the main pigment that is aimed to be obtained.
Once the dyes are extracted, next process will be the evaluation of the viability of their employment as raw material in new dyeing process. The fabrics will be characterized in terms of reproducibility, difference of colour obtained
depending on the employment of different batches and every parameter considered relevant.
The dyeing tests will consist of a laboratory simulation of the industrial-scale process so the process to dye the textile will be by exhausting because is the most common used. In these processes, textile remains in contact with the
treatment bath previously prepared throughout the duration of the process and under the conditions specified in the corresponding curve of treatment. Time runs and the reagent is transferred from the bath to the fiber.
During this action, it will be determined the conditions of the process to obtain the best performance, e.g the largest amount of the dye bath through the fiber and define the auxiliary products to be employed in order to achieve this
The waste water obtained from dyeing processes must be treated to this low biodegradability. In SEACOLORS we will also validate the reduction of waste water treatments needed by the high biodegradability of the dyes developed, and
by the reduction of auxiliaries employed in the dyeing process in order to archive the proposed objectives.