Adsorption of heavy metal ions on surface of functionalized oil palm empty fruit bunch fibers: single and binary systems

The functionalization of surface charges on oil palm empty fruit bunch (EFB) fibers was modified by grafted carboxylic acid and polymer amine groups. Single and binary adsorption of Cu(II), Ni(II), Mo(VI) and As(V) were investigated by competitiveness in the adsorbents. The mechanism of each metal ion was deliberately studied on kinetics-diffusion (intraparticle diffusion) and isotherm adsorption models (Langmuir and Freundlich). Competitiveness of metal ions was found in the selectivity of Cu(II) > Ni(II) and Mo(VI) > As(V) in the binary solution. The regeneration of adsorbents was performed up to five cycles of an adsorption/desorption process and the reduction of adsorption performance was less than 14.5%. Therefore, this promises low-cost adsorbents for metal ion uptake, showing potential for removal and recovery in industrial wastewater treatment

Extraction of cellulose and microcrystalline cellulose from kenaf

Bast and core of kenaf which categorized as agriculture residues were used in the extraction of cellulose due to its lignocellulosic nature. In this study, cellulose was extracted from the raw kenaf by using 10% alkaline peroxide pre-treatment followed by extraction process at 85 °C using the combination of 20% (v/v) formic acid and 10% (v/v) hydrogen peroxide that formed peroxy acid. The extracted cellulose was further hydrolyzed by 1.5 M of hydrochloric acid at 80 °C to yield microcrystalline cellulose (MCC). Relatively high yield of 71.81% (w/w) and 94.8% (w/w) were achieved for extracted cellulose and MCC, respectively. Based on FESEM, the average diameter of kenaf cellulose and MCC were 12.43 μm and 11.64 μm, respectively with the separated fibrils and rod-like structural. FT-IR spectral peaks observed in the cellulose and MCC revealed that most hemicellulose and lignin were eliminated during the chemical treatments. XRD analysis results exhibited that kenaf MCC gives the sharpest and highest peak s compared to others. The results also showed that the crystallinity index of extracted cellulose and MCC were increased to 60.5% and 62.3%, respectively

3D Printed Functionalized Nanocellulose as an Adsorbent in Batch and Fixed-Bed Systems

Nanocellulose, a refined form of cellulose, can be further functionalized on surface-active sites, with a catalyst as a regenerative agent. Newly developed adsorbents are expected to have the characteristics of good and rapid adsorption performance and regeneration properties with flexible structure using 3D printing technology. In this work, the adsorption performance of 3D printed functionalized nanocellulose was investigated using batch and fixed-bed column adsorption. Kinetics adsorption studies were divided into different adsorption models, with the pseudo-second order model showing a better correlation coefficient than the pseudo-first order and intraparticle diffusion models. The Langmuir and Thomas models were used to calculate the adsorption performance of batch and fixed-bed columns. Given the catalytic activity of Fenton oxidation, the fixed-bed column was regenerated up to five adsorption-desorption cycles, suggesting satisfactory performance of the column, with a slightly reduced adsorption capacit

Preparation and characterization of Fe3O4/regenerated cellulose membrane

In this study, magnetic cellulose membranes (MCM) have been prepared by using cotton linter as cellulose source and NaOH/urea as cellulose solvent at different magnetite content. Cellulose was dissolved in pre-cooled NaOH/urea solvent at -13°C to form cellulose solution. The cellulose solution then was mix with magnetite (Fe3O4) nanoparticles synthesized via co-precipitation method of Fe2+ and Fe3+ in the presence of sodium hydroxide (NaOH) to form MCM. The MCMs formed at different percentage of Fe3O4 i.e., 10, 20 and 30%. Analysis from vibrating sample magnetometer (VSM) shows that the saturation magnetization of the MCM increase as the percentages of Fe3O4 nanoparticles increased. However, the addition of Fe3O4 nanoparticles in the regenerated cellulose membrane has decreased the crystallinity index of MCM. The surface morphology of the MCM showed that the Fe3O4 nanoparticles were dispersed in the pore of the membrane. Tensile test showed decreasing in the tensile strength of the cellulose membrane with the addition of Fe3O4 nanoparticle

Potential of membrane technology for treatment and reuse of water from old mining lakes

The El-Nino phenomenon in early 2014 contributed to the lack of water supply in most Southeast Asian countries. Suggestions have since been made to ensure the continuity of water supply, one of which involves membrane technology to treat mine water so that it is compatible for citizens’ use. Accordingly, the objective of this research was to study the efficiency of membrane technology in treating mine water. Our elucidation of all the parameters has showed that the best attainable classification is at Class IV. Although it was still regarded as polluted, the treated mine water can be used as water supply reservoir. For the membranes tested such as ultrafiltration 10 kDa, 5 kDa and reverse osmosis, the percentage of rejection for chemical oxygen demand is 21-72%, 40-96% for total suspended solids and 21-72% for ammonia nitrogen. The pH also gradually shifted to almost neutral after the filtration

Penyahwarnaan efluen kilang minyak kelapa sawit (POME) melalui proses pengoksidaan Fenton secara berterusan menggunakan limonit sebagai pemangkin

Industri minyak sawit mempunyai impak yang besar ke atas alam sekitar terutama di Malaysia. Efluen kilang minyak sawit (POME) merupakan air buangan yang mengandungi sebatian organik yang berasal daripada bahan boleh urai dan sedia direput oleh mikroorganisma. Teknologi rawatan POME masa kini banyak bertumpu kepada kaedah biologi untuk mengurangkan permintaan oksigen kimia (COD), permintaan oksigen bio-kimia (BOD) dan jumlah karbon organik (TOC). Walau bagaimanapun, kebanyakan proses biologi tidak dapat menguraikan warna yang terdapat dalam POME. Kajian ini mengkaji potensi teknologi pengoksidaan Fenton menggunakan biji limonit sebagai pemangkin kepada hidrogen peroksida untuk merawat POME selepas proses rawatan biologi yang diperoleh daripada kilang minyak kelapa sawit. Keputusan menunjukkan dengan hanya 50 mM H2O2 boleh menyahwarnakan POME sebanyak 800-1000 PtCo secara berterusan dengan pengekalan masa 1 jam pada pH 3

Membran selulosa kenaf terjana semula daripada larutan akues NaOH/urea yang digumpal menggunakan asid sulfurik

Membran selulosa terjana semula (MS) daripada pulpa teras kenaf telah berjaya dihasilkan menggunakan kaedah pra penyejukan dan digumpal menggunakan larutan asid sulfurik. MS disediakan daripada pelarutan selulosa kenaf dalam larutan akues NaOH/urea dan larutan selulosa seterusnya digumpal dengan H2SO4 pada kepekatan 5-12 peratus berat (% bt.) selama 1-10 min. Pengaruh kepekatan penggumpal H2SO4 dan masa penggumpalan ke atas struktur, saiz liang, sifat mekanik dan ketelusan cahaya MS telah dikaji menggunakan pembelauan sinar-X (XRD), imbasan mikroskop elektron tekanan boleh ubah (VPSEM), penguji regangan dan spektrofotometer ultra-violet sinar tampak (UV-vis). Keputusan VPSEM menunjukkan perubahan saiz liang membran bergantung kepada kepekatan larutan penggumpal H2SO4, manakala masa penggumpalan tidak mempengaruhi saiz liang membran. Membran yang direndam dengan larutan penggumpal pada kepekatan 10 % bt. dan masa pembekuan yang sederhana iaitu 5 min menunjukkan sifat mekanik yang lebih baik dengan nilai kekuatan regangan masing-masing 41.9 dan 43.5 MPa. Oleh itu, kajian ini dapat memberikan maklumat mengenai penyediaan MS dengan pelbagai saiz liang dan sifat mekanik dengan pengubahsuaian kepekatan dan masa penggumpalan

Rice husk activated carbon with NaOH activation: physical and chemical properties

Activated carbon was produced from rice husk by activating with NaOH. Three types of samples were made at 850, 750, and 650 °C activation temperature. The properties of the samples were determined. The activated carbons have surface area of 429.82 m2 /g from 850 °C activation, 121.39 m2 /g (750 °C) and 93.89 m2 /g (650 °C). The results were higher than rice husk carbon without activation (0.23 m2 /g). The activated carbons have mesopore size (2-50 nm). Proximate and ultimate analyses of the samples were also determined. The activation process increased the carbon content of the samples. Physical characteristics of the activated carbons were shown from the XRD analysis. FTIR demonstrated the different functional of the rice husk carbon and activated. The SEM images showed the pores on the surface of the activated carbon due to the NaOH activation

BOOSTING ENZYMATIC HYDROLYSIS OF PRESSURIZED AMMONIUM HYDROXIDE PRETREATED EMPTY FRUIT BUNCH USING RESPONSE SURFACE METHODOLOGY

Oil palm Empty Fruit Bunch (EFB) was pretreated using Pressurized Ammonium Hydroxide (PAH) and was employed as Lignocellulosic Biomass(LCB) substrate for the investigation on the monomeric fermentable sugar production using the enzymatic hydrolysis process. Cellulose saccharification in enzymatic hydrolysis into a high yield fermentable sugar is an important step in Biochemical Conversion Technology (BCT). In order to determine the optimum variable conditions that can produce a high yield of fermentable sugar, a statistical approach using Response Surface Methodology (RSM) was performed in this study. Three independent variables, enzyme loading (15-50 FPU/g glucan), hydrolysis temperature (45-60°C), and agitation of the hydrolysis process (100-180 rpm) were investigated at five different levels (-α,-1, 0, +1, +α) of operating conditions and the experimental conditions were randomly setup using the Design of Experiment software. The regression models indicated that R 2 for glucose and xylose concentration was 95 and 88% showing the experimental variations were well defined by the models. For the lack of fit test, with p-values > 0.05 for both concentration sugars, 0.218 for glucose and 0.055 for xylose, it proves that the model was significant to the prediction models. The optimal conditions for the enzymatic hydrolysis of the EFB were determined at 32.5 FPU/g of glucan of enzyme loading, 50°C of hydrolysis temperature, and 140 rpm of agitation speed. The validation of the model at the optimum conditions produced a maximum glucose concentration of 8.78 ± 0.01 g/L (conversion of 81.7 ± 0.02 %, and yield of 332.95 ± 0.98 g/kg dry EFB), with a corresponding xylose concentration of 4.40 ± 0.01 g/L (conversion of 57 ± 0.35% and yield of 173.72 g/kg dry EFB)

Nanocellulose-Based Biomaterial Ink Hydrogel for Uptake/Release of Bovine Serum Albumin

This study explores the potential of using nanocellulose extracted from oil palm empty fruit bunch (OPEFB) as a biomaterial ink for 3D printing. The research focuses on using nanocellulose hydrogels for the controlled uptake and release of proteins, with the specific protein solution being Bovine Serum Albumin (BSA). To provide a suitable material for the bioprinting process, the study examines the characteristics and properties of the printed hydrogels through various analyses, such as morphology, functional group, crystallinity, and compression test. Several parameters, such as initial concentration, temperature, and the presence of calcium chloride as an additional crosslinker, affect the protein uptake and release capabilities of the hydrogel. The study is important for biomedicine as it explores the behavior of protein uptake and release using nanocellulose and 3D printing and can serve as a preliminary study for using hydrogels in biological materials or living cells