Kinetics study of copper (Cu) and chromium (Cr) adsorption using green mussel shells (Perna viridis) adsorbent

Research has been carried out on making green mussel shell adsorbents to absorb Cu and Cr metals. The study of making green mussel shell adsorbents was carried out by thermal activation using a furnace. The results of the activated adsorbent were characterized using FTIR and SEM-EDX. Furthermore, the adsorbent was used to absorb Cu and Cr metal by using several variations, namely variations in the temperature of the adsorbent activation, adsorbent weight, pH, and contact time, and knowing the kinetic model by determining the reaction order. The results obtained from the characterization of green mussel shells contain elements of Ca, about 67.56% at an activation temperature of 500 °C and 67.34% at an activation temperature of 900 °C. The optimum conditions for Cu metal adsorption by green shell adsorbent were obtained at an activation temperature of 500 °C, using an adsorbent of 1 gram under pH 10 and a contact time of 40 minutes. Whereas for Cr metal absorption, the activation temperature was 900 °C, the mass used was 1.5 grams with pH 7 and the contact time was 40 minutes. The adsorption kinetics model of green mussel shells adsorbent on Cu and Cr metals followed pseudo-second-order

The effect of essential oil concentrations on particle size of kencur (Kaempferia galanga L.) nanoemulsions with maltodextrin and tween 80 as emulgators

Kencur (Kaempferia galanga L.) essential oil nanoemulsion was proposed to replace baby powder which has been banned in several countries. This study aimed to determine the effect of various kencur essential oil concentrations on particle size and to measure their stability during storage. This research was initiated by examining essential oil quality and followed by the formulation of nanoemulsion with maltodextrin and tween 80. PSA characterized it, and stability was observed for six weeks. The results showed that the essential oil of kencur was of good quality with a clear yellow color oil, a distinctive odor of kencur, 0.933 g/mL of density, and a 1.480 refractive index value. This value is considered standard in Indonesia's National standards (SNI) of essential oil. The L1, L2, L3, and L4 nanoemulsion formulas have particle sizes: 20.4 nm, 20.3 nm, 21.7 nm, and 26.2 nm, respectively. L1 (0.475) is chosen as the best formula based on the PI value. The formulas showed good stability and homogeneity for six weeks of storage. Its pH is also persistent at room temperature (30 °C) or in refrigerator storage (7 °C)

Rhodamine-B Dyes Adsorption by Beads Alginate

Research has been carried out on the adsorption of rhodamine-b dye by alginate beads. The production of alginate granules was carried out at a concentration of 3.5% alginate powder. Identification of functional groups was carried out by FT-IR and water absorption test resulted in a maximum capacity of 96.24% at 90 minutes. Determination of adsorption capacity was carried out by UV-VIS spectrophotometer at a maximum contact time of 30 minutes and a maximum pH at pH 7, and resulted in adsorption maximum concentration at 30 ppm is 15.954 mg/L with adsorption capacity of 4.7862 mg/

Rhodamine-B Dyes Adsorption by Beads Alginate

Research has been carried out on the adsorption of rhodamine-b dye by alginate beads. The production of alginate granules was carried out at a concentration of 3.5% alginate powder. Identification of functional groups was carried out by FT-IR and water absorption test resulted in a maximum capacity of 96.24% at 90 minutes. Determination of adsorption capacity was carried out by UV-VIS spectrophotometer at a maximum contact time of 30 minutes and a maximum pH at pH 7, and resulted in adsorption maximum concentration at 30 ppm is 15.954 mg/L with adsorption capacity of 4.7862 mg/

Characteristic comparison of cornstarch-based bioplastics using kaolin, microcrystalline cellulose and chitosan as fillers

In the study, the basic material for making bioplastics was corn starch with the addition of kaolin, microcrystalline cellulose, and chitosan as filler variations, as well glycerol as a plasticizer. The method used was the blending method. The characterization included the absorption test for water resistance, biodegradation test, tensile and elongation strength test, and functional group analysis using FTIR. Among fillers, the best bioplastic characteristic bioplastic was obtained with filler kaolin with the water absorption value of 88.62%, a tensile strength value of 1.44 x10-3 MPa, and the elongation strength value of 5.04%. Nearly 80% of the material was degraded in 15 days. Spectra of FTIR showed the appearance of some functional groups from starch, filler, and plasticizer, which meant that the process of bioplastic manufacturing was physical mixing

Penghilangan Zat Warna menggunakan Kompleks Polielektrolit Kitosan-Alginat

Telah dilakukan sintesis kompleks polielektrolit (PEC)kitosan-alginat dalam bentuk film dan beads. Material dibuat dengan menggunakan biopolimer kitosan dan alginat yang bersifat ramah lingkungan untuk pengujian adsorpsi terhadap zat warna. Karakterisasi PEC kitosan-alginat dilakukan dengan FTIR(Fourier Transform Infra Red), uji stabilitas medium asam basa serta uji kapasitas adsorpsi terhadap zat warna. Hasil karakterisasi menunjukan terjadinya pergesaran vibrasi pada hasil sintesis yang semakin tajam dan PEC kitosan-alginat stabil pada pH >4. Kapasitas adsorpsi optimum diperoleh sebesar 0,676 mg/g pada menit ke- 45 untuk PEC kitosan-alginat dalam bentuk beads dan 0,0135 mg/g pada menit ke-30 untuk bentuk film. Model kinetika semua adsorbenmenunjukkan mengikuti orde dua semu