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Waste cigarette filter (WCF) is one of the most common wastes found in the environment. Cigarette filters contain up to 96% cellulose acetate (CA), which can be used as a material for membrane fabrication. However, the CA-based membrane from WCF posed a weak mechanical property (brittle). Therefore, the objective of this work is to improve mechanical property of CA-based membrane from WCF by preparing blend membranes with polyvinylidene fluoride (PVDF) polymer and evaluate their performance for filtration of real river water containing high natural organic matter (NOM) concentrations. The variations of WCF and PVDF used were 100:0, 75:25, 50:50, 25:75, and 0:100. The membranes were then characterized to determine the morphology, pore size and pore size distribution, hydrophilicity, mechanical properties, and filtration performance of the membrane using clean water and river water. The SEM test results showed the presence of spherulites on the surface of the blend membrane, indicating that crystallization occurred during membrane formation. The spherulites resulted in smaller pore size, narrower pore size distribution, higher hydrophilicity, and mechanical properties. Meanwhile, the filtration test results showed that blend membranes produced higher permeability compared to pristine WCF, PVDF, and commercial-based CA membranes, where the result of river water permeability was in the range of 875–1062.5 L/m2.h.bar. The membrane fouling formation was aligned well with the result of permeability and is dominated by irreversible fouling formation from the dynamic cake layer built on the membrane surface, with NOM rejections of 26.6–33.8%, suggesting the need for further developments.

Abstract Cigarette smoke contains many chemicals, including nicotine, which is harmful and can cause health problems such as carcinogenesis disease, cardiovascular, respiratory, renal, and reproductive systems. Removal of nicotine from mainstream smoke can be done through adsorption with filters or solid adsorbents. In this study, we explored the use of activated carbons for the removal of nicotine from cigarette mainstream smoke. Activated carbons were prepared from dried hemp (Cannabis sativa) stem at an activation temperature of 350–550 °C using phosphoric acid as an activating agent. The results showed that the activated carbons with variable surface functional groups and porosity exhibited high efficiency for nicotine adsorption, removing 68–88% of nicotine from cigarette mainstream smoke. Through X-ray photoelectron spectroscopy and temperature-programmed desorption analyses, we identified that oxygen-containing functional groups, particularly carboxylic groups, exhibited a superior ability to adsorb nicotine. The computational analysis with DFT simulations further supported the importance of oxygen-containing surface functional groups in facilitating nicotine adsorption, with the carboxylic group providing the lowest adsorption energy among other functional groups.

Zeolite has become a promising material that can potentially play a pivotal role in resolving environmental crises. Among zeolite families, MCM-22 zeolite shows outstanding intrinsic properties associated with the topology and porous structure, offering ion-exchange advantages for catalytic activity processes. The synthesis of MCM-22 zeolite becomes challenging when concerning the cost and catalytic performance. To overcome this bottleneck, we demonstrate a sustainable route of a hydrothermal process using natural resources as starting materials. Rice husk from agricultural waste was used as a silica source while natural clays (kaolin and bentonite) were applied as alumina sources. The products from natural sources were compared with the use of commercial starting materials, e.g., NaAlO2 (for alumina) and Na2SiO3 and TEOS (for silica), in points of crystal, compositional, and morphological views. We showed that the high purity of MCM-22 zeolite can be obtained from rice husk silica (RHS) and aluminosilicate gel (ASG) extracted from kaolin, while the use of ASG extracted from bentonite tended to be unsuitable to generate the zeolite formation. We also studied the effects of reaction time and the ratio of RHS/ASG on the crystallinity and surface area of MCM-22. The architecture and acidity of an optimal product were explored by Nuclear magnetic resonance spectroscopy and Temperature-programmed desorption of ammonia, demonstrating the success of achieving well acidity.

River water can be used as a source of drinking water. However, it is vital to consider the existence of natural organic matter (NOM) and its possible influence on water quality (low turbidity, high color). The level of NOM in river water significantly impacts the ecosystem’s health and the water’s quality, and needs to be removed. A membrane-based approach is attractive for treating NOM successfully, but is still hindered by the membrane fouling problem. This study aims to develop polyvinylidene fluoride (PVDF)-based membranes customized for NOM removal from river water. The anti-fouling property was imposed by a coating of tannic acid (TA) and Fe3+ on the pre-prepared PVDF membrane. The results show that the TA–Fe coatings were effective, as demonstrated by the FTIR spectra, SEM, and EDS data. The coatings made the membrane more hydrophilic, with smaller pore size and lower clean water permeability. Such properties offer enhanced NOM rejections (up to 100%) and remarkably higher fouling recovery (up to 23%), desirable for maintaining a long-term filtration performance.

Abstract Glycerol is a low-cost byproduct of the biodiesel manufacturing process, which can be used to synthesize various value-added chemicals. Among them, 1,2-propanediol (1,2-PDO) is of great interest because it can be used as an intermediate and additive in many applications. This work investigated the hydrogenolysis of glycerol to 1,2-PDO over Co–Cu bimetallic catalysts supported on TiO2 (denoted as CoCu/TiO2) in aqueous media. The catalysts were prepared using the co-impregnation method and their physicochemical properties were characterized using several techniques. The addition of appropriate Cu increased the glycerol conversion and the 1,2-PDO yield. The highest 1,2-PDO yield was achieved over a 15Co0.5Cu/TiO2 catalyst at 69.5% (glycerol conversion of 95.2% and 1,2-PDO selectivity of 73.0%). In the study on the effects of operating conditions, increasing the reaction temperature, initial pressure, and reaction time increased the glycerol conversion but decreased the selectivity to 1,2-PDO due to the degradation of formed 1,2-PDO to lower alcohols (1-propanol and 2-propanol). The reaction conditions to obtain the maximum 1,2-PDO yield were a catalyst-to-glycerol ratio of 0.028, a reaction temperature of 250 °C, an initial H2 pressure of 4 MPa, and a reaction time of 4 h.

Selective hydrogenation of furfural to furfuryl alcohol over CuAl2O4 catalysts is studied in a batch reactor using a range of solvents of varying chemical properties. We find that the reactions in branched alcohols provide higher furfuryl alcohol yields compared to linear alcohols. Besides, the reactions performed in nonane and decane provide excellent furfuryl alcohol yields of 96%. In situ FTIR analysis indicates that the carbonyl group of furfural is preferentially adsorbed leading to such high catalyst performance. Importantly, the efficient production of furfuryl alcohol in immiscible solvents minimizing downstream process is achieved in this integrative reaction-separation concept.

The oxidative coupling of methane (OCM) is an attractive route to convert natural gas directly into value-added chemical products (C2+). This work comparatively investigated SiO2- or La2O3-supported Na2WO4-MnxOy (denoted as NWM) catalysts in powder and fiber forms. The powder catalysts were prepared using a co-impregnation method and the fiber catalysts were prepared successfully using an electrospinning technique. The NWM/La2O3 fiber catalysts were activated at low temperature (500 °C) and had a 4.7% C2+ yield, with the maximum C2+ yield of 9.6% at 650 °C, while the NWM/SiO2 fiber catalyst was activated at 650 °C and had a maximum C2+ yield of 20.4% at 700 °C. The XPS results in the O 1s region indicated that NWM/La2O3 had a lower binding energy than NWM/SiO2, suggesting that the lattice oxygen species is easily released from the catalyst surface and creates vacancy sites that enhance performance. The stability test of the catalysts indicated that the La2O3-containing catalysts had excellent activity and high thermal stability, while the SiO2-containing catalysts had a higher C2+ yield when the prepared catalysts were compared at 700 °C. Considering the same component catalysts, the fiber catalysts achieved higher performance because their heat and mass transfer properties were enhanced.

One of the most potential byproducts of transesterification that has been produced in a large amount is glycerol. Converting glycerol into Solketal via catalytic acetalization using natural zeolites is an interesting route to improve its economic value. Natural zeolites are abundant and inexpensive catalysts with low crystallinity and surface area. Thus, modification of its properties is required to improve material characteristics and alter the transesterification reaction. Investigation of the effect of NaOH concentration treatment on the Bayah natural zeolite was performed from 0.1 to 0.4 M NaOH at 65 °C and 30 min of mixing. Physical characteristic analysis, such as X-ray diffraction, proves that natural zeolite from Bayah was identified predominantly as clinoptilolite. The crystallinity significantly improved after NaOH treatment and could reach a high crystallinity material at 0.4 M NaOH. The textural properties using nitrogen physisorption are also shown by a high surface area of 164 m2/g (from parent Z-0.4; 19 m2/g). In addition, the mesopore volume also improved after alkali treatment, increasing the mass transfer of molecules. The application of modified natural zeolite for glycerol acetalization was tested in a glass tube reactor at a temperature of 50 °C for 90 min showing a significant alteration in conversion from 3.5 % (parent zeolite) to 90.4 % (modified zeolite).

Sulfonated magnetic carbon nanoparticles (SMCNs) were synthesized from eucalyptus oil via co-pyrolysis with ferrocene and sulfonation by H2SO4. Catalytic performance of SMCNs for conversion of fructose to 5-hydroxymethylfurfural was examined within a designated range of reaction temperature (120–180 °C) and time (30–240 min). 84% conversion of fructose and 51.6% yield of 5-hydroxymethylfurfural could be achieved with catalyst-to-fructose mass ratio of 0.167 at 180 °C and the reaction time of 30 min. The magnetic property of SMCNs also facilitated recovery and recycling of the spent catalyst. Additionally, more than 50% yield of 5-hydroxymethylfurfural could be achieved after three cycles.

The catalytic deoxygenation of coconut oil was performed in a continuous-flow reactor over bimetallic NiCo/silicoaluminophosphate-11 (SAPO-11) nanocatalysts for hydrocarbon fuel production. The conversion and product distribution were investigated over NiCo/SAPO-11 with different applied co-reactants, i.e., water (H2O) or glycerol solution, performed under nitrogen (N2) atmosphere. The hydrogen-containing co-reactants were proposed here as in-situ hydrogen sources for the deoxygenation, while the reaction tests under hydrogen (H2) atmosphere were also applied as a reference set of experiments. The results showed that applying co-reactants to the reaction enhanced the oil conversion as the following order: N2 (no co-reactant) < N2 (H2O) < N2 (aqueous glycerol) < H2 (reference). The main products formed under the existence of H2O or glycerol solution were free fatty acids (FFAs) and their corresponding Cn−1 alkanes. The addition of H2O aids the triglyceride breakdown into FFAs, whereas the glycerol acts as hydrogen donor which is favourable to initiate hydrogenolysis of triglycerides, causing higher amount of FFAs than the former case. Consequently, those FFAs can be deoxygenated via decarbonylation/decarboxylation to their corresponding Cn−1 alkanes, showing the promising capability of the NiCo/SAPO-11 to produce hydrocarbon fuels even in the absence of external H2 source.

During the production of oil and gas, a large amount of oily wastewater is generated, which would pollute the environment if discharged without proper treatment. As one of the most promising treatment options, membrane material used for oily wastewater treatment should possess desirable properties of high hydraulic performance combined with high membrane fouling resistance. This project employs the vapor induced phase separation (VIPS) technique to develop a hydrophilic polyvinylidene fluoride (PVDF) membrane with polyethylene glycol (PEG) as an additive for produced water treatment. Results show that thanks to its slow nonsolvent intake, the VIPS method hinders additive leaching during the cast film immersion. The results also reveal that the exposure of the film to the open air before immersion greatly influences the structure of the developed membranes. By extending the exposure time from 0 to 30 min, the membrane morphology change from typical asymmetric with large macrovoids to the macrovoid-free porous symmetric membrane with a granular structure, which corresponds to 35% increment of steady-state permeability to 189 L·m−2h−1bar−1, while maintaining >90% of oil rejection. It was also found that more PEG content resides in the membrane matrix when the exposure time is extended, contributes to the elevation of surface hydrophilicity, which improves the membrane antifouling properties. Overall results demonstrate the potential of VIPS method for the fabrication of hydrophilic PVDF membrane by helping to preserve hydrophilic additive in the membrane matrices.

First we survey the scope and level of research activities in nanoparticle technology (NPT) in ASEAN by looking at relevant international journal publications (2006–2012) in terms of absolute numbers (AN), numbers of publications per million population (PMP) and per billion USD GDP (PBG). Obviously, the statistics show that, within ASEAN, the strength of Singapore covers a wide range of nanotechnology fields and applications, including carbon materials, biosensors, bioelectronics, and pharmaceutics. Malaysia places emphasis on alloys & compounds, carbon materials, and separation technology. Thailand’s emphasis is on molecular modeling, carbon materials, and biosensors. When classification is made on the morphology of nanoparticles mentioned in the titles, the topmost are nanotubes (including CNT, SWCNT, MWCNT) at 392 out of 612 (64.1%), followed by generic nanoparticle/nanopowder and nanofiber (including nanowire, nanorods). Next we look closer at 2 nanoparticle R&D organizations in Thailand, namely, CEPT (CU) and NANOTEC together with their alliances. The interest in nanotechnology of SCG (Siam Cement Group), a leading Thai industrial conglomerate, will also be briefly introduced. .