Recrystallization of Triple Superphosphate Produced From Oyster Shell Waste for Agronomic Performance and Environmental Issue

Calcium dihydrogen phosphate monohydrate [Ca(H2PO4)2·H2O] (a fertilizer) was successfully synthesized by the recrystallization process by using a prepared triple superphosphate (TSP) that derived from oyster shell waste as starting material. This bio-green, eco-friendly process to produce an important fertilizer can promote a sustainable society. The shell-waste-derived TSP was dissolved in distilled water and kept at 30, 50, and 80 °C. Non-soluble powder and TSP solution were obtained. The TSP solution fraction were then dried and the recrystallized products (RCP30, RCP50, and RCP80) were obtained and confirmed as Ca(H2PO4)2·H2O. Whereas the non-soluble products (NSP30, NSP50, and NSP80) were observed as calcium hydrogen phosphate dihydrate (CaHPO4·2H2O). The recrystallized yields of RCP30, RCP50, and RCP80 were found to be 51.0%, 49.6%, and 46.3%, whereas the soluble percentages were 98.72%, 99.16%, and 96.63%, respectively. RCP30 shows different morphological plate sizes, while RCP50 and RCP80 present the coagulate crystal plates. X-ray diffractograms confirm the formation of both the NSP and RCP. The infrared adsorption spectra confirmed the vibrational characteristics of HPO42‒, H2PO4‒ and H2O existed in CaHPO4·2H2O and Ca(H2PO4)2·H2O. Three thermal dehydration steps of Ca(H2PO4)2·H2O (physisorbed water, polycondensation, and re-polycondensation) were observed. Ca(H2PO4)2 and CaH2P2O7 are the thermodecomposed products from the first and second steps, whereas the final product is CaP2O6.

Comparison of Chitosan Characterization from Mussel Shell Waste Using Varying Concentration of Solvents

Massive amounts of mussel shell waste are generated and wasted from the aquaculture processing sectors, resulting in environmental pollution. This material contains chitosan as a valuable compound characterized as a non-toxic structural component with several food processing applications or medicinal applications. In this research, mussel shells were processed using different solvents concentrations in several stages: demineralization, deproteination, decolourization, and deacetylation. Our result showed that the C2 samples gained a high degree of deacetylation (31.8±0.21%) with low moisture and ash content and medium weight of yield. Further research is recommended to purify chitosan using various instrumentation and assess its bioactivity.

Valorization of Waste Lignocellulose to Furfural by Sulfonated Biobased Heterogeneous Catalyst Using Ultrasonic-Treated Chestnut Shell Waste as Carrier

Recently, the highly efficient production of value-added biobased chemicals from available, inexpensive, and renewable biomass has gained more and more attention in a sustainable catalytic process. Furfural is a versatile biobased chemical, which has been widely used for making solvents, lubricants, inks, adhesives, antacids, polymers, plastics, fuels, fragrances, flavors, fungicides, fertilizers, nematicides, agrochemicals, and pharmaceuticals. In this work, ultrasonic-treated chestnut shell waste (UTS-CSW) was utilized as biobased support to prepare biomass-based heterogeneous catalyst (CSUTS-CSW) for transforming waste lignocellulosic materials into furfural. The pore and surface properties of CSUTS-CSW were characterized with BET, SEM, XRD, and FT-IR. In toluene–water (2:1, v:v; pH 1.0), CSUTS-CSW (3.6 wt%) converted corncob into furfural yield in the yield of 68.7% at 180 °C in 15 min. CSUTS-CSW had high activity and thermostability, which could be recycled and reused for seven batches. From first to seventh, the yields were obtained from 68.7 to 47.5%. Clearly, this biobased solid acid CSUTS-CSW could be used for the sustainable conversion of waste biomasses into furfural, which had potential application in future.

PEMANFAATAN BATOK KELAPA SEBAGAI MEDIA PEMBUATAN BIO-INSTRUMEN MUSIK

<p>Bio-musical instruments can be defined as musical instruments made from plant wastes in the surrounding <br />environment. One of the plant waste that is easily found in the community is coconut shell. Coconut shells are <br />often overlooked for their use as a creative medium, especially in the field of music. Musical instruments are the <br />main media for creativity in the art of music. The rise of musical instruments or musical instruments with high <br />prices has become one of the inhibiting factors for young people to be creative in the field of music. Seeing this <br />phenomenon, it is deemed necessary to develop people's creativity in making their own musical instruments at <br />economical prices but still able to compete with manufactured musical instruments. In making this bio-<br />instrument, the method used consists of problem identification, preparation, application, and evaluation. <br />Through this method, the results obtained in the use of coconut shell waste into creative media are the Kalimba <br />instrument played by plucking the iron keys as the source of the tone, while the coconut shell is used as the main <br />medium for the sound resonance of the Kalimba instrument. Kalimba is classified into a type of lamellophone <br />instrument, which is a musical instrument that has a tongue or a thin plate. In addition to the easy-to-use <br />manufacturing process, the tools and materials in making these instruments are also easy to find and can even <br />take advantage of used materials. The results of making bio-musical instruments are expected to become a <br />reference and reference for academics and non-academics, regarding how to make musical bio-instruments <br />using coconut shell waste. <br /> <br />Keywords : Bio-Music Intrument, Coconut Shells, Kalimba</p>