Sintesis Silika Metode Sol-gel sebagai Penyangga Fotokatalis Tio2 terhadap Penurunan Kadar Kromium dan Besi

SYNTHESIS OF SILICABYSOL-GELMETHODAS SUPPORTOF PHOTOCATALYST TiO2 TO DECREASE CONCENTRATION OF CHROMIUMAND IRON. Silica is a material which attracted the researcher's attention because of its extensive application and easy making. One method to make silica is sol-gelmethod which the parameters can bemodified such as catalyst concentration and calcination temperature. The result is amorphous silica with lowest density that the silica can be used as support photocatalyst. This reaserch has purpose to make a TiO2-SiO2 photocatalyst to decrease metals concentration. Stage of the research is synthesis of silicawith various of ammonia concentrations and calcination temperature, immobilization of TiO2 on SiO2, and TiO2-SiO2 photocatalytic test on concentration of chromium and iron metal from water Cikijing River. To determine the functional groups, morphology, crystalline form, composition of the TiO2 in photocatalyst TiO2-SiO2, and metal concentration, there should be analysis by using FTIR, SEM, EDX, XRD, and AAS. These research resulted silica which was synthesized with ammonia 12.5% and 25% and with calcination temperature 400oC, 500oC, and 600oC. The result of FTIR showed peaks at wave number 3447 cm- 1 (OH stretching), 1638 cm-1 (bending Si-O), and 1107 cm-1 (bending Si-O-Si). The result of XRD TiO2-SiO210% showed a peak at 2θ = 25.26o is anatase TiO2 and 2θ = 23.86o is amorphous SiO2 thus known that TiO2 immobilized on SiO2 with composition of TiO2 is 10.05%fromthe results of SEM-EDX. Test of photocatalytic TiO2-SiO2 10% has optimum activity to decrease concentration of chromium metal amounted to 95.30% and iron amounted to 93.62% at first concentration of chromium 3.832 mg/L and iron 2.039 mg/L

Composation of Polyaluminum Chloride with Hydroxyapatite and Its Application for Separation of Hexavalent Chromium Ions

Chromium is the dominant heavy metal in liquid waste from the leather tanning industry, wood preservation and textile processing. Generally chromium waste is found as trivalent and hexavalent chromium ions. Hexavalent chromium ion is dangerous for humans because of its carcinogenic nature, which can lead to skin irritation, lung cancer, kidney and stomach disorders. Coagulation-flocculation (CF) is a method used to reduce hexavalent chromium ion levels. Polialuminum chloride (PAC) has been widely used in water treatm ent using the CF method. Unfortunately, however, the PAC stability is poor, the coagulation efficiency is low, and the floc formation time is slow. In addition, PAC can produce Al3+ which is toxic in processed water. But its toxicity can be overcome by adding donor ligands that contain oxygen such as hydroxides, carboxylic acids and phosphates, such as hydroxyapatite (HA). In addition, the addition of HA with the optimum composition and pH at PAC can increase the performance of PAC. This study aims to optimize the PAC/HA combination at various pH so as to reduce the concentration of hexavalent chromium ion, controlled by UV-VIS spectroscopy. The highest reduction in Cr (VI) ion content was obtained by PAC, but the highest stability was obtained by the composition of PAC/HA 4: 6

Karakterisasi Biodiesel Dari Minyak Kemiri Sunan Dengan Katalis Heterogen Silika Terimpregnasi Kalsium Oksida (Cao/sio2)

Biodiesel komersial umumnya diproduksi dari minyak sawit yang telah menjadi kontroversi karena minyak sawit merupakan minyak pangan dan tanaman kelapa sawit memanfaatkan lahan subur. Salah satu jenis minyak nabati potensial sebagai bahan baku pembuatan biodiesel adalah minyak kemiri sunan (Reutealis trisperma (Blanco) Airy Shaw). Minyak kemiri sunan bersifat non-pangan sehingga tidak akan berkompetisi dengan kebutuhan pangan. Dalam pembentukan biodiesel, penggunaan katalis basa homogen pada tahap trans-esterifikasi berpotensi menimbulkan beberapa masalah, salah satunya akibat keberadaan asam lemak bebas (ALB). Penelitian ini bertujuan menyiapkan katalis padat heterogen berupa katalis SiO2 terimpregnasi CaO (CaO/SiO2), mempelajari pengaruh tahap esterifikasi terhadap Perubahan kadar ALB minyak, dan menguji aktivitas katalis CaO/SiO2 pada tahap trans-esterifikasi dalam pembentukan biodiesel. Katalis CaO/SiO2 disiapkan dengan metode sol-gel dari bahan alam (cangkang telur dan sekam padi). Kadar ALB dari minyak kemiri sunan divariasikan melalui tahap esterifikasi selama 1; 1,5; dan 2 jam dengan bantuan katalis H2SO4. Sedangkan tahap trans-esterifikasi dilakukan pada suhu 60°C, rasio mol minyak terhadap metanol sebesar 1:9, lama reaksi dua jam, dan kadar katalis CaO/SiO2 sebanyak 3%. Hasil penelitian menunjukkan bahwa tahap esterifikasi selama 1; 1,5; dan 2 jam telah mampu menurunkan kadar ALB minyak dari 12,5% (tanpa esterifikasi) menjadi 0,65%; 0,58%; dan 0,54%. Biodiesel dari minyak kemiri sunan yang disintesis dengan bantuan katalis CaO/SiO2 pada kondisi optimal di tahap trans-esetrifikasi memenuhi standar SNI 7182-2015 mengenai biodiesel, untuk parameter densitas, viskositas, kadar air, bilangan iodin, dan bilangan cetana

Pengolahan Limbah Organik Rumah Tangga sebagai Bahan Baku Pakan Ikan

Limbah organik mempunyai banyak dampak pada manusia dan lingkungan sekitar. Limbah organik dapat bersumber dari limbah rumah tangga seperti sayur-sayuran, buah-buahan busuk dan dari dedaunan yang berasal dari lingkungan sekitar Limbah organik yang bersumber dari rumah tangga memiliki kandungan protein kasar 10,89-15,58%, lemak 7,77-9,70% dan serat kasar 4,88-9,13%, sehingga sangat berpotensi untuk dijadikan bahan pakan alternatif sumber protein dan energi dalam pakan ikan. Penelitian ini bertujuan untuk mengetahui pemanfaatan limbah organik dari rumah tangga sebagai alternatif pakan ikan serta memberikan informasi dan pengetahuan kepada masyarakat tentang cara mengolah limbah organik rumah tangga menjadi pakan ikan. Selanjutnya target khusus yang ingin dicapai adalah memberikan ilmu atau pengetahuan tentang pemanfaatan limbah organik kepada masyarakat. Metode yang akan digunakan adalah metode analisis deskriptif dengan pendekatan kuantitatif berupa pengumpulan data kuesioner dari masyarakat. Berdasarkan data kuesioner yang dibagikan pada responden, banyak masyarakat yang belum mengolah dan memanfaatkan limbah organik menjadi bahan yang bermanfaat seperti alternatif pakan ikan

Biocomposite of Hydroxyapatite From Chicken Egg Shells and Biochar From Rice Husk as an Adsorbent for Copper Ion and Methylene Blue

The growth of industrial activity and increasing use of water have effected to the releasing of various pollutants into the waters, as methylene blue and copper ions. Excess levels of methylene blue and copper ions in the waters can cause ecosystem damage. This study aims to obtain biocomposites of hydroxyapatite from chicken egg shells and biochar from rice husk as well as their adsorption ability to inorganic pollutants (Cu (II)) and organic pollutant (methylene blue). Hydroxyapatite (HA) was synthesized by calcining chicken eggshells into CaO powder which is then reacted with (NH4)2HPO4. Furthermore HA was mixed with biochar from rice husk to form biocomposites. The ability of the biocomposite adsorption test was carried out by varying the time and initial concentration of the metal solution and methylene blue. Based on the results of the study, HA-biochar composites showed the best contact adsorbing time for methylene blue and copper ions 50 and 30 minutes respectively. Testing of biocomposite adsorption ability to the initial concentration of methylene blue as much as 12.79 ppm showed that the biocomposite is able to adsorb methylene blue to a residual concentration of 1.15 ppm or the maximum percentage of methylene blue that can be adsorbed by 91%. The ability of HA-biochar composites to adsorb methylene blue is better than its constituent materials (HA and biochar). HA-biochar composites was also able to adsorb Cu ions with an average adsorption percentage of 79.45% from the initial concentration

Identification of Electrical Conductivity of The Volcanic Soil on Fertilizer-Exposed Agricultural Field (Case Study on Agricultural Field Parompong, West Java)

Parongpong volcanic soil is a type of Andosols soil used for short-lived crop farming. Increased agricultural production is usually by giving excessive fertilizer that causes contamination of farmland and leaves residue residues that contaminate the soil. The research has been done using geophysical methods to determine the soil electrical properties of the Huma EC technology, which results in resistivity value and converts it into conductivity. Data collection on agricultural and non-agricultural land was measured as a comparison. The result shows that agricultural land’s conductivity value is higher than non-agricultural land. The range of conductivity values in non agricultural land is 1.44 - 15.11 mmhos/cm. The content of conductivity values in non-non-agricultural land is 0.72 - 2.7 mmhos/cm. The value can be used as a Parongpong volcanic agricultural area conductivity database.   Keywords: agricultural, electrical conductivity, cation transfer capacity, contamination, HUMA-EC&nbsp