| dc.description.abstract | The synthesis of hydrogel composite based on kulit ari kopi has been carried
out by crosslinking method. The method applied by the addition of lignin H2SO4
isolated from kulit ari kopi was 0.05%, 0.1%, 0.2%, 0.3%, the addition of 2 g of CNF
and the addition of 5% PVA for each variation. From the prepared composite
hydrogel samples, physical and chemical properties were tested using several
measurement techniques for several characterizations. Characterizations applied
include characterization of water absorption, methylene blue absorption,
characterization of functional groups, characterization of microcrystalline properties,
morphological characterization and characterization of mass reduction on thermal
treatment. From the results of the characterization, the results are interrelated and
mutually supportive. The best sample belongs to the hydrogel sample HYD-005
which has a water absorption capacity of 55% and an effective absorbance of
methylene blue which is 81% in every hour applied. The measurement of the
absorbance of methylene blue is also applied to variations in temperature, namely
350 °C, 450 °C, 550 °C. From the applied temperature variation, the absorbance
values obtained were 59%, 53% and 81%, respectively. Of all the samples
synthesized, the HYD-005 sample has the best value from other samples, this is
supported by each data of characterization and analysis obtained. | en_US |
