Peach palm and cassava wastes as biosorbents of tartrazine yellow dye and their application in industrial effluent

In this study, the wastes from cassava (CAW) and peach palm (PPW) agro-industries were investigated as potential low-cost biosorbents for removing the tartrazine yellow dye (TAR). The by-products were prepared by washing and drying steps and characterized into physicochemical parameters and microstructure. The effects of contact time, pH, dosage and dye concentration were analyzed for the biosorbents in comparison to commercial activated carbon (AC). The biosorbents were applied to the treatment of an effluent from a juice industry containing TAR. Cellulose was the main component of the biosorbents (31.47–51.20 g 100 g-1), which was correlated to the functional groups identified by ATR-FTIR spectra and the materials had a porous surface. The zero point of charge was 3.75 for PPW and 4.60 for CAW. The pH parameter had a significant effect on the adsorption process, with the maximum values of adsorption being reached at pH 2.0, with removal of 94.7% for PPW, 74.4% for CAW and 97.7% for AC, at the dosage of 7.5 g L-1 at 25.0 ºC. The adsorption of TAR was fast in the early stages, and at 120 min the three adsorbents reached the equilibrium. Isotherms of adsorption showed that Langmuir’s and Freundlich’s models fitted the best to the CAW and PPW experimental data, respectively. The wastes evaluated in this work can be an interesting alternative to TAR adsorption in the industrial effluent without being subjected to chemical treatments.

Influence of Internal Structure of the Sorbents on Diazepam Sorption from Simulated Intestinal Fluid

The capacity of natural Na-montmorillonite and activated charcoal for sorption of diazepam from simulated intestinal fluid (SIF) was studied. The main characteristics of the sorbents were determined. In order to characterize the sorption process of diazepam the influence of the pH, contact time and ethanol presence in SIF was analyzed. Adsorption isotherms for the diazepam-activated charcoal and diazepam-natural Na-montmorillonite systems were determined. The Langmuir isotherm model provided a very good description of diazepam sorption. Furthermore, the pH-drift method was used to determine the specific pH at zero point of charge (pHzpc) of the sorbents. The obtained results show that the internal structure of the sorbents and pH of the SIF solutions are very important for diazepam sorption. Both the surface of the activated charcoal and natural Na-montmorillonite are positively charged below the pHzpc so the sorption of diazepam is higher below this point and occur by van der Waals forces. The presence of ethanol in simulated intestinal fluid lowers the adsorption of diazepam on both sorbents.

Analisis Sifat-sifat Fisikokimia Tanah pada Ordo Tanah Ultisol di Lahan Kering Aceh Besar

Abstrak. Sifat-sifat fisikokimia tanah di antaranya adalah muatan tiitk nol, muatan permanen, dan muatan variabel. Penelitian ini bertujuan untuk mengkaji sifat-sifat fisikokimia tanah pada ordo Ultisol di lahan kering Aceh Besar dengan menggunakan metode deskriptif kuantitatif. Sampel tanah diambil pada setiap lapisan horizon dari profil tanah ordo Ultisol yang berasal dari Desa Jalin Jantho. Sebelum dianalisis, sampel tanah dikeringanginkan selama dua minggu dan kemudian digerus dan disaring dengan ayakan 0,5 mm. Analisis dilakukan di Laboratorium Penelitian Tanah dan Tanaman Fakultas Pertanian Universitas Syiah Kuala, Banda Aceh. Parameter yang di analisis yaitu tekstur, pH, C-organik, kation basa dapat dipertukarkan (Ca, Mg, K, Na), kation asam dapat dipertukarkan (Al dan H), KTK jumlah kation, dan pH0. Hasil penelitian menunjukkan bahwa Ultisol memiliki liat yang tinggi dengan pH masam – netral. Penurunan C-organik seiring bertambahnya kedalaman tanah,diikuti oleh penurunan pH0 menurut kedalamn tanah. Karakteristik muatan pada Ultisol Jantho memiliki tanah bermuatan negatif dan didominasi oleh muatan campuran.Analysis of Soil Physicochemical Properties on Ultisol Soil Ordersin Dry Land of Aceh BesarAbstract. The physicochemical properties of the soil include zero point of charge, permanent charge, and variable charge. This study aims to examine the physicochemical properties of Ultisol soil order in dry land of Aceh Besar using quantitative descriptive methods. Soil samples were taken at each horizon layer soil profile of the Ultisol order from Jalin Jantho Village. Before being analyzed, soil samples were dried for two weeks and then crushed and filtered with a 0.5 mm sieve. The analysis was carried out at the Soil and Plant Research Laboratory of the Faculty of Agriculture, Syiah Kuala University, Banda Aceh. The parameters analyzed were texture, pH, C-organic, interchangeable base cations (Ca, Mg, K, Na), interchangeable acid cations (Al and H), CEC number of cations, and pH0. The results showed that Ultisol has a high clay with acidic - neutral pH. Decrease in C-organic with increasing soil depth, followed by a decrease in pH0 according to soil depth. The characteristics of the charge on Ultisol Jantho has negatively charged soil and is dominated by mixed loads.

Pengaruh Partikel Nano Abu Vulkanik dan Batuan Fosfat terhadap Muatan Variable dan Kemasaman Andisol

ABSTRACTThe effect of particle nano volcanic ash and rock phosphate on variable charge or zero point of charge (pH0) and soil acidity of AndisolsThis experiment aimed to find out the effect of particle nano volcanic ash and rock phosphate on variable charge or zero point of charge (pH0) and soil acidity of Andisols from Ciater Subang-West Java. This experiment was conducted from October 2016 to March 2017 at Soil fertility and Plant Nutrition Laboratory and Physic Soil Laboratory of Soil Science and Land Resources Department, Faculty of Agriculture, Universitas Padjadjaran, Jatinangor. The experiment was arranged in Completely Randomized Design consisted of two factors. The first factor was particle of nano volcanic ash consisted of 4 levels. The second factor was particle of nano rock phosphate consisted of 4 levels and 3 replications. The results showed that there was no interaction between nano particle of volcanic ash and rock on zero point of charge (pH0), but there was interaction effect on pH-H2O. Combination of 2.5% nano particle of volcanic ash and 0% nano particle of rock phosphate could reduce the value of zero point of charge (pH0) as much 28.57%. Combination of 5% volcanic ash nano particle and 7.5% rock phosphate nano particle dosage was the best treatment and could increase the value of soil acidity or pH-H2O until 20.36%.Keywords: Andisol, pHο, Rock phosphate, Volcanic ashABSTRAKTujuan dari penelitian ini adalah untuk mengetahui pengaruh partikel nano abu vulkanik dan batuan fosfat terhadap muatan variable atau titik muatan nol (pH0) dan kemasaman tanah Andisols Ciater Subang-Jawa Barat. Penelitian ini dilaksanakan pada bulan Oktober 2016 sampai dengan Maret 2017 di Laboratorium Kesuburan Tanah dan Nutrisi Tanaman serta Laboratorium Fisika Tanah Departemen Ilmu Tanah dan Sumber Daya Lahan, Fakultas Pertanian, Universitas Padjadjaran, Jatinangor. Penelitian ini menggunakan Rancangan Acak Lengkap pola faktorial dengan dua faktor. Faktor pertama adalah partikel nano abu vulkanik yang terdiri dari 4 taraf. Faktor kedua adalah partikel nano batuan fosfat yang terdiri dari 4 taraf, diulang sebanyak 3 kali. Hasil penelitian menunjukkan bahwa tidak terjadi interaksi antara partikel nano abu vulkanik dan batuan fosfat terhadap titik muatan nol (pH0) namun terjadi interaksi antara kedua perlakuan tersebut terhadap kemasaman tanah (pH-H2O). Komposisi dosis yang paling baik dalam menurunkan pH0 adalah 2,5% partikel nano abu vulkanik dan 0% partikel nano batuan fosfat yaitu sebesar 28,57%, sedangkan komposisi dosis yang paling baik dalam meningkatkan pH-H2O adalah 5% partikel nano abu vulkanik dan 7,5% partikel nano batuan fosfat yaitu sebesar 20,36%.Kata Kunci: Abu vulkanik, Andisol, Batuan fosfat, pH0

ADSORÇÃO DO CORANTE TURQUESA REMAZOL POR CASCA DE MANDIOCA (Manihot esculenta Crantz)

Neste trabalho a casca de mandioca (Manihot esculenta Crantz) foi empregada como adsorvente para a remoção do corante têxtil turquesa remazol a partir de efluentes aquosos. O adsorvente foi caracterizado por espectroscopia vibracional na região do infravermelho e pH no ponto zero de carga (pHZPC). Os grupamentos superficiais do adsorvente foram compatíveis com os de demais materiais lignocelulósicos e o valor estimado para o pHZPC foi 6,0. Foram determinados o tempo de contato (240 min) e o efeito do pH na adsorção, sugerindo um mecanismo eletrostático predominante para remoção do corante, já que pH ácidos favoreceram à adsorção. Os dados cinéticos foram modelados segundo Lagergren, Ho e Avrami, sendo que este último explicou melhor os dados experimentais. A quantidade máxima adsorvida encontrada para as condições otimizadas de adsorção (pH 2,0, te = 240 min e T = 25 oC) foi 30 mg.g-1. Os resultados experimentais foram modelados pelas equações de Freundlich, Langmuir, Sips e Tóth. Os parâmetros: coeficiente de determinação e qui-quadrado mostraram que modelos de Langmuir, Sips e Tóth são os que melhor explicam os resultados. Os dados experimentais indicam que a casca de mandioca pode perfeitamente ser utilizada como adsorvente para a remoção de corantes têxteis em efluentes industriais.Palavras-chave: Casca de mandioca. Material bioadsorvente. Adsorção de corante têxtil. ADSORPTION OF TURQUOISE DYE BY CASSAVA PEEL (Manihot esculenta Crantz)Abstract: In this work cassava peel (Manihot esculenta Crantz) was employed as adsorbent by removal of the textile dye remazol turquoise. The adsorbent was characterized by vibrational infrared spectroscopy and pH at zero point of charge (pHZPC). The surface functional groups were consistent with those of other lignocellulosic materials and the estimated pHZPC value was 6.0. The contact time (240 min) and the effect of the pH on the adsorption were determinate, and both suggest an electrostatic predominant mechanism to remove the dye, due the adsorption has been favored by acidic pH. The kinetic data were modeled according to Lagergren, Ho and Avrami, and among them, the latter was the best fitted with the experimental data. The maximum adsorbed amount found under optimized conditions (pH 2.0, te = 240 min and T = 25 oC) was 30 mg g-1. The experimental results were modeled by Freundlich, Langmuir, Sips and Tóth equations. The determination coefficient and chi-square parameters showed that the the best models that fitted to the experimental data were Langmuir, Sips and Tóth. Experimental data show that the peel cassava can perfectly be used as adsorbent for removal of textile dyes from industrial effluents.Keywords: Cassava peel. Bioadsorbent Material. Adsorption of textile dyestuff. ADSORCIÓN DEL COLORANTE TURQUESA REMAZOL POR LA CORTEZA DE YUCA (Manihot esculenta Crantz)Resumen: En este trabajo la corteza de la yuca (Manihot esculenta Crantz) fue utilizada como adsorbente para la eliminación del colorante textil turquesa remazol de efluentes acuosos. El adsorbente fue caracterizado por espectroscopia vibracional en la región infra-rojo y pH en el punto de carga cero (pHZPC). Los grupos de la superficie del adsorbente fueron consistentes con los de otros materiales lignocelulósicos y el valor estimado para la pHZPC fue 6,0. Fueron determinados el tiempo de contacto (240 min) y el efecto del pH en la adsorción, sugeriendo un mecanismo electrostático predominante para la eliminación del colorante, ya que pH ácidos favorecieron la adsorción. Los datos cinéticos fueron modelados según Lagergren, Ho y Avrami, apesar de que este último explica mejor los datos experimentales. La cantidad máxima adsorbida encontrada para la condiciones optimizadas de la adsorción (pH 2,0, te = 240 min y T = 25 ºC) fue de 30 mg.g-1. Los resultados experimentales fueron modelados por las ecuaciones de Freundlich, Langmuir, Sips y Tóth. Los parámetros: coeficiente de determinación y qui-cuadrado mostraron que los modelos de Langmuir, Sips y Tóth son los que mejor explican los resultados. Los datos experimentales indican que la corteza de la yuca puede ser utilizada perfectamente como adsorbente para la eliminación de colorantestextiles en efluentes industriales.Palabras clave: Corteza de yuca. Material bioadsorbente. Adsorción del colorante textil.

Effects of Some Multivalent Ions on Coagulation and Electrokinetic Behaviours of Colemanite Particles

The effects of magnesium, barium, aluminium, and ferric cations as multivalent ions on the coagulation and electrokinetic behaviours of colemanite have been investigated in relation to pH and cation concentration. The zero point of charge for colemanite was determined to be at pH 10.2. The positive surface charge of colemanite increased in the presence of multivalent ions at pH values below the zero point of charge. Also, these ions changed the zeta potential of colemanite from negative to positive within the pH range 10.2 to 12. In the experiments, the coagulation of colemanite with ferric ions was more efficient than with the other ions and the effect of ferric ions varied considerably depending on the concentration and pH. The coagulation recovery values of colemanite suspension increased quickly up to 2.5 × 10–3 M concentration of ferric ions and the maximum value (~93 %) was obtained at a pH of 11.5. It was also found that the coagulation behaviour of the colemanite suspension in the presence of multivalent cations was in good agreement with the electrokinetic characteristics.

Adsorption Characteristics for Lead(II) by Fulvic Acid-Modified Vermiculite

Fulvic acid-modified vermiculite (FA-Ver) was prepared by mixing vermiculite and fulvic acid in a suspension. The XRD patterns showed that the vermiculite in FA-Ver possesses an irregular stacking of layers supported and non-supported by fulvic acid particles. The specific surface area (SSA), cation exchange capacity (CEC), pH at zero point of charge (pHZPC), and surface charge at pH 6.0 of FA-Ver was 379.35 m2/g, 52.17 cmol/kg, pH 2.36, and -0.442 mmol/g, respectively. The SSA, CEC and surface negative charge of FA-Ver increased and the pHZPC decreased compared to the corresponding values of vermiculite. Langmuir and Freundlich isotherms fitted the adsorption data for Pb(II) by HA-vermiculite well (R2=0.988 and 0.982, respectively). The Freundlich correlation coefficient of vermiculite was low (R2=0.954) and that of FA-Ver was slightly higher (R2=0.980). At pH 6.0, the Langmuir maximum adsorption capacities for Pb(II) of vermiculite and FA-Ver were 11.86 and 19.41 mg/g, respectively.

Lead(II) Adsorption by Raw and Acid-Activated Vermiculite

Acid-activated vermiculite (AAV) was prepared by treating raw vermiculite (RV) at 80°C with HCl solution. The surface properties and Pb(II) adsorption characteristics of RV and AAV were studied. The specific surface area (SSA), cation exchange capacity (CEC), pH at zero point of charge (pHZPC), and surface charge at pH 5.8 of AAV were 287.62 m2/g, 24.85 cmol/kg, pH 3.06, and -0.361 mmol/g, respectively. Compared to RV, the SSA, CEC and surface charge of AAV increased, but the value of pHZPC decreased. At pH 5.8, the maximum adsorption capacities (qmax) for Pb(II) of RV and AAV were 10.72 and 18.53 mg/g, respectively. The adsorption data for Pb(II) by RV and AAV could be well fitted using Langmuir isotherm (R2 =0.990 and 0.995, respectively)