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All Journal Jurnal Natur Indonesia agriTECH Indonesian Journal of Chemistry Journal Of Chemical Process Engineering
Thamrin Usman
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Tanjungpura University, Jl. Ahmad Yani Pontianak, Kalimantan Barat 79124
Aerospace Engineering Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Engineering

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Transepidermal Water Loss Value Comparison Between Tengkawang and Durian Seed Oil Lotion Febriaty, Irma Ramadhani; Usman, Thamrin; Alimuddin, Andi Hairil
Jurnal Natur Indonesia Vol 18, No 1 (2020)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (860.444 KB) | DOI: 10.31258/jnat.18.1.20-30

Abstract

Body epidermis has an important health function to prevent body dehydration. This research aims to compare Transepidermal Water Loss (TEWL) values between durian seed oil and tengkawang oil. Skin that had been applied with tengkawang oil and durian seed oil lotion were tested for irritation and TEWL values. The tengkawang oil had an acid number of 17 g/mol and contained  8.54 % free fatty acid, while the durian seed oil had an acid number of 6.34 g/mol and contained 2.89 % free fatty acid.  Irritation testing was done using lotion containing 100 % of each oil. TEWL analysis on skin applied with the tengkawang oil lotion after 1 hour showed that the lotion could reduce epidermal water evaporation by 35.23 % compared to the skin condition before treatment.  Epidermal water evaporation reduction at the second, third and fourth hours after the tengkawang oil lotion application was 31.33 %, 33.93 % and 27.9 %, respectively. TEWL analysis on skin applied with the durian seed oil lotion after 1 hour showed that the lotion could reduce epidermal water evaporation by 11.34 % compared to the skin condition before treatment.  Epidermal water evaporation was reduced 14.64 %, 10.53 % and 2.99 % at the second, third and fourth hours after application of the durian seed oil. Based on these results, it can be concluded that tengkawang oil gives better TEWL values compared to durian seed oil.
Reducing Free Fatty Acids in Crude Palm Oil Using Diethylene Glycol and Zinc(II) Chloride Based Deep Eutectic Solvent Suriyanti, Lieli; Usman, Thamrin; Rahmalia, Winda
Indonesian Journal of Chemistry Vol 24, No 3 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.85980

Abstract

Deep eutectic solvents (DES) were prepared by precise combinations of mol fractions of chemical compounds, resulting in a lowered melting point due to hydrogen bonding. This research aimed to elucidate the physicochemical attributes of DES and its effectiveness in mitigating free fatty acid (FFA) levels in crude palm oil (CPO). Zinc(II) chloride (ZnCl2) served as the hydrogen bond acceptor (HBA) while diethylene glycol (DEG) as the hydrogen bond donor (HBD). Characterization included freezing point, density, viscosity, conductivity, and pH determination. At a ZnCl2 mol fraction of 0.30, the resulting DES exhibited homogeneity with transparent liquid properties, featuring a freezing point below −10 °C, density of 1.42 g/mL, viscosity of 1933.40 cP, conductivity of 66.13 µS/cm, and pH 3.42. FTIR spectra confirmed hydrogen bond interactions between HBA and HBD. Applied to CPO at a 1:1 volumetric ratio (DES:CPO), with 2 h of stirring time at 50 °C, FFA content decreased from 4.11 to 0.86%. This research highlights DES as an environmentally sustainable purification agent, significantly reducing FFA levels in unrefined palm oil.
Studi Komparasi Penggunaan TiO2 Anatase dan P25 sebagai Anoda untuk Sel Surya Tersensitasi Bixin Septiani, Septiani; Naselia, Uray Amira; H. Silalahi, Imelda; Usman, Thamrin; Rahmalia, Winda
Journal of Chemical Process Engineering Vol. 6 No. 1 (2021): Journal of Chemical Process Engineering
Publisher : Fakultas Teknologi Industri - Universitas Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33536/jcpe.v6i1.821

Abstract

Penelitian ini dilakukan untuk menentukan kinerja sel surya yang menggunakan TiO2- anatase dan TiO2-P25 sebagai anoda. Bixin digunakan sebagai sensitizer. Bixin diekstraksi dan diisolasi dari biji kesumba. Bixin dianalisis menggunakan spektrofotometer UV-Vis dan FTIR. Hasil analisis menggunakan spektrofotometer UV-Vis menunjukkan adanya 3 puncak karakteristik bixin pada 488, 459, 430 nm. Spektra FTIR bixin ditandai dengan adanya serapan pada bilangan gelombang 3183 cm-1 mengindikasikan vibrasi renggang -OH yang berasal dari gugus karboksilat; pada 2955, 2924, dan 2852 cm-1 vibrasi renggang H-C-H; pada 1716 cm-1 vibrasi renggang C=O; pada 1608 cm-1 vibrasi tekuk O-H; pada 1563 dan 1518 cm-1 vibrasi renggang C=C (alkena); pada 1379 cm-1 vibrasi tekuk C-H; pada 1255 cm-1 vibrasi renggang C-O; pada 1161 cm-1 vibrasi simetri dan asimetri C-O-C (kelompok ester); serta pada 1012 cm-1 vibrasi renggang C-H. Kinerja sel surya yang menggunakan TiO2-antase menunjukkan efisiensi konversi energi maksimum yang lebih tinggi (0,027%) jika dibandingkan dengan TiO2-P25 (0,006%) di bawah intensitas cahaya 100 W/m2.
Synthesis of Biodiesel in Low-Grade Palm Oil using Geopolymer-ZnO Catalyst Nabila, Yaasinta Lafasha; usman, Thamrin; Alimuddin, Andi Hairil
agriTECH Vol 44, No 3 (2024)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/agritech.80468

Abstract

This study aimed to synthesize biodiesel (fatty acid methyl ester) from low-grade palm oil using geopolymer-ZnO catalyst. The activity of catalyst was tested by mixing low-grade palm oil and methanol in a mole ratio of 1:10, with varying catalyst concentrations of 1%, 3%, and 5% at a temperature of 67 o C and different time intervals. Subsequently, the progression of the reaction was monitored using thin-layer chromatography (TLC). The results showed that catalyst ratios of 1:0, 1:1, and 1:2 provided complete conversion at concentrations of 3% and 5%. Geopolymer-ZnO catalyst reuse test was carried out using a concentration of 5%, followed by washing with n-hexane. After drying at 100 o C, the sample was reused in biodiesel synthesis. The reuse test findings showed optimum results at 1:2 variation and 2 hours of reaction time with total methyl ester conversion. In addition, the majority of the experiments performed were carried out using a 1:1 variation with a maximum of 3 repetitions, which consistently showed total conversion to methyl ester. Catalyst used was then characterized using FTIR, XRD, and XRF instruments, with the analysis results confirming that it was geopolymer-ZnO. Methyl ester obtained was analyzed using GC-MS, and the findings showed that the main compositions included methyl oleate (47.35%) and methyl palmitate (40.13%).
Co-Authors Andi Hairil Alimuddin Heni Pujiastuti Imelda Hotmarisi Silalahi Irma Ramadhani Febriaty Nabila, Yaasinta Lafasha Naselia, Uray Amira Suriyanti, Lieli Winda Rahmalia