Nita Aryanti

Surface modification of cellulose acetate membrane using thermal annealing to enhance produced water treatment

This study is performed primarily to investigate the effect of surface modification of cellulose acetate using thermal annealing on the enhancement of membrane performance for produced water treatment. In this study, Cellulose Acetate membranes were casted using dry/wet phase inversion technique. The effect of additive and post-treatment using thermal annealing on the membrane surface were examined for produced water treatment. Therma annealing was subjected to membrane surface at 60 and 70 °C for 5, 10 and 15 second, respectively. Membrane characterizations were done using membrane flux and rejection with produced water as a feed, Scanning Electron Microscopy (SEM) and Fourier Transform Infra Red (FTIR) analysis. Experimental results showed that asymmetric cellulose acetate membrane can be made by dry/wet phase inversion technique. The results from the Scanning Electron Microscopy (FESEM) analysis was also confirmed that polyethylene glycol as additivie in dope solution and thermal annealing was affected...

Lignin isolation process from rice husk by alkaline hydrogen peroxide: Lignin and silica extracted

Biomass is one of abundance resources in the world. Biomass consists of three main materials such as cellulose, hemicelluloses and lignin. Therefore, biomass can be referred to lignocellulosic material. Both the cellulose and hemicelluloses fractions are polymers of sugars, and thereby a potential source of fermentable sugars, or other processes that convert sugars into products. Lignin is a polymer compound which contains of phenolic compounds. Rice husk is one of biomass, which has high contain of lignin. Rice husk has special characteristics because of silica content. The aim of this paper is to analyze lignin and silica extracted during lignin isolation process of rice husk using alkaline hydrogen peroxide. Three main variables such as solvent/solid ratio, concentration of hydrogen peroxide and pH of the mixture are studied. The optimum conditions for lignin isolation are at solvent/solid ratio 9:1 ml/gr, hydrogen peroxide concentration of 1.5%v and pH of the mixture of 11.

Effect of deacetylation on functional properties of glucomannan

Glucomannan is one of the highest viscosity polysaccharides with high water absorbing capacity. This property limits glucomannan applications; hence, it requires modifications. Glucomannan has 5-10% acetyl group which confers its functional properties. Replacing the acetyl with alkali transforms the functional characteristic of modified glucomannan. The aim of this study was to determine the effect of deacetylation conditions on the functional properties of glucomannan of A. oncophyllus. Effects of concentration of Na2CO3 (0.1-0.5 M), reaction time (1-5 h) and temperature deacetylation (40-80°C) were studied on glucomannan solubility, viscosity and water binding capacity (WBC). Deacetylation conditions affected solubility, viscosity and WBC of deacetylated glucomannan differently. Concentration of Na2CO3 showed negative impact on solubility, viscosity and WBC of deacetylated glucomannan. Solubility increased with increasing temperature and extending duration of deacetylation. Meanwhile, temperature and re...

Micellar-enhanced ultrafiltration membrane (MEUF) of Batik wastewater using Cetylpyridinium chloride surfactant

In batik production, reactive dyes such as remazol, indigosol, naphtol and rapid are used in the dying process. Batik wastewater contains high level of reactive dyes, wax and sodium salts and is characterized with high Chemical Oxygen Demand (COD), Total Suspended Solids (TSS) as well as high concentration of phenol and Ammonia. Micellar-Enhanced Ultrafiltration Membrane (MEUF) is one of promising technology to separate low molecular weight substances such as dyes. The MEUF process involves combination of ultrafiltration membrane and surfactant at concentration higher than surfactant’s Critical Micelle Concentration (CMC). This technique combines high selectivity of reverse osmosis membrane and high flux of ultrafiltration membrane but with lower pressure. Ultrafiltration of batik waste water without surfactant (UF) and with addition of surfactant (MEUF) were studied in order to compare the performance of both systems. The Batik wastewater were obtained from batik industry in Semarang and Surakarta, Centr...

Analysis of rotating membrane emulsification performance for oil droplet production based on the Taylor vortices approach

ABSTRACT Membrane emulsification processes generally employ a cross flow of the continuous phase in order to produce shear stress. Modification of membrane emulsification for the o/w emulsion using the rotating system has been introduced such as the use of stirred cells or a rotating tubular membrane in a stationary liquid. This paper presents an examination of membrane rotation speed on droplet characteristics. The performance of rotating membrane emulsification on o/w droplet size, the coefficient of variation, and size distribution was investigated. In addition, the operated flow regime in the rotating membrane emulsification is addressed. It has been found that overall the droplet size decreased with the increase of membrane rotation speed. The droplet size below the pore size could be produced when operating at a high rotation speed (1500 rpm). The decrease of droplet size was believed due to the action of Taylor vortices on droplet detachment. Analysis of membrane rotation speed proposed that action of Taylor vortices facilitates droplet detachment. Calculation of Taylor numbers (having a value of 0–629) confirmed that the rotating membrane emulsification produced laminar flow with vortices.

Synthesis of Natural Surfactant of Sodium Lignosulfonate from Rice Husk Lignin by Ultrasound Assisted - Sulfonation

Sodium lignosulfonate (SLS) is one of natural surfactant that can be modified from lignin. The utilization of natural surfactant of SLS is widely studied by researchers. This paper will study the synthesis of a natural surfactant of SLS from rice husk lignin by ultrasound assisted – sulfonation and the characteristics of SLS based on FTIR spectra. The reaction was carried out at the temperature of 60 °C and the time of 30 minutes. From the experiment can be concluded that sulfonation process with ultrasonic irradiation has advantages compared with conventional heating, i.e. lower temperature, shorter time and higher yield.

Physicochemical Properties of Glucomannan-Alginate as Vitamin C Excipient

Physicochemical Properties of GlucomannanAlginate as Vitamin C Excipient Wardhani, Dyah Hesti Chemical Engineering Department, Faculty of Engineering, Diponegoro University Hapsari, Farida D. Chemical Engineering Department, Faculty of Engineering, Diponegoro University Suryana, Kazenina M. Chemical Engineering Department, Faculty of Engineering, Diponegoro University Aryanti, Nita Chemical Engineering Department, Faculty of Engineering, Diponegoro University 他

Fouling reduction by ozone-enhanced backwashing process in ultrafiltration of petroleum-based oil in water emulsion

Ultrafiltration membrane has been successfully applied for oily waste water treatment. However, one significant drawback of membrane technology is fouling which is responsible for permeate flux decline as well as reducing membrane performance. One method commonly used to reduce fouling is a backwashing process. The backwashing is carried out by a push of reversed flow from permeate side to the feed side of a membrane to remove fouling on the membrane pore and release fouling release fouling layer on the external side. However, for adsorptive fouling, the backwashing process was not effective. On the other hand, Ozone demonstrated great performance for reducing organics fouling. Hence this research was focused on backwashing process with ozone for removing fouling due to ultrafiltration of petroleum based oil emulsion. Gasoline and diesel oil were selected as dispersed phase, while as continuous phase was water added with Tween 80 as a surfactant. This research found that the Ozone backwashing was effectiv...

Characteristics of waste water treatment plant sludge and coal co-combustion

Wastewater Treatment Plant (WWTP) in electricity generation process produces sludges which are hazardous and toxic. As a consequence of clean production principle, the sludges were re-recombusted with coal in the boiler. Combination of coal co-combustion with household waste and biomass waste has been applied, but utilization of WWTP sludge co-combustion with coal was not found. As the WWTP sludge characteristics, chemical composition and ash fusion were unknown, phenomenon and effective combustion of coal-sludge co combustion were very interesting to be explored. This paper was aimed to study the sludge characteristics, to evaluate thermal energy of sludge combustion, to investigate the effect of sludge-coal co combustion on emissions and potential of boiler slagging. Experimental works comprised of coal characterization, proximate analysis of sludge-coal mixtures, ultimate analysis, chemical composition of ash as well as ash fusion temperature. Research found that the sludge had calorific value of 427.3...