• Carbon letters
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• v.17 no.1
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• pp.1-10
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• 2016

Lignocellulosic biomass conversion to biofuels such as ethanol and other value-added bio-products including activated carbons has attracted much attention. The development of an efficient, cost-effective, and eco-friendly pretreatment process is a major challenge in lignocellulosic biomass to biofuel conversion. Although several modern pretreatment technologies have been introduced, few promising technologies have been reported. Microwave irradiation or microwave-assisted methods (physical and chemical) for pretreatment (disintegration) of biomass have been gaining popularity over the last few years owing to their high heating efficiency, lower energy requirements, and easy operation. Acid and alkali pretreatments assisted by microwave heating meanwhile have been widely used for different types of lignocellulosic biomass conversion. Additional advantages of microwave-based pretreatments include faster treatment time, selective processing, instantaneous control, and acceleration of the reaction rate. The present review provides insights into the current research and advantages of using microwave-assisted pretreatment technologies for the conversion of lignocellulosic biomass to fermentable sugars in the process of cellulosic ethanol production.

• Journal of Pharmaceutical Investigation
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• v.6 no.2
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• pp.88-94
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• 1976

This paper attempted to investigate the effect of pretreatment with carbon tetrachloride on absorption, excretion, protein binding, and biological half-life of sulfisoxazol from rats and rabbits. Absorption of sulfisoxazol was found to decrease in severe damage rats, compared with that of normal rats, but in mild rats, absorption of sulfisoxazol was similar to that of nomal rats. Absorption of sulfisoxazol was decreased significantly in severe damage rabbit pretreated with carbon tetrachloride but in mild damage rabbit, absorption of sulfisoxazol was not influenced significantly. Pretreatment with carbon tetrachloride gave the effect on clearance of sulfisoxazol in part but protein binding percent of sulfisoxazol was not influenced by concentration of carbon tetrachloride.

• Journal of Korean Society on Water Environment
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• v.20 no.5
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• pp.447-451
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• 2004

The various pretreatment processes were evaluated to remove organic pollutants of weathered oil contaminated seawater(WOCS) for reverse osmosis desalination process, Biodegradation, coagulation, ultrafiltration, advanced oxidation processes and granular activated carbon filtration were used to evaluate the potential of organic pollutants removal in WOCS. Dissolved Organic Carbon(DOC) was almost not removed by biodegradation in WOCS. DOC was removed by 25% and 10% with the addition of $FeCl_3$ and PAC in WOCS, respectively. The removal efficiency using ultrafiltration(WOCS 500) was about 20% of DOC and 40% of $E_{260}$, respectively. In AOP application of WOCS, the removal of organic materials was improved up to 60% by the combination of $UV/O_3$ compared to UV process. However, 98% of DOC in woes could be removed by granular activated carbon filtration. It is revealed that activated carbon filtration is the best process for the pretratment of DOC removal.

• Carbon letters
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• v.12 no.3
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• pp.167-170
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• 2011

Petroleum pitch-based activated carbons (ACs) were obtained in this work from a combination of pretreatment with different amounts of potassium permanganate ($KMnO_4$) and chemical activation with potassium hydroxide. The surface characteristics of the pitch after the $KMnO_4$ pretreatment were characterized by means of Fourier transform infrared spectroscopy (FT-IR). The structural characteristics of the pitch after the $KMnO_4$ pretreatment were determined by means of X-ray diffraction. The influence of the $KMnO_4$ treatment on the textural properties of the petroleum pitch-based ACs was investigated by means of $N_2$/77K adsorption isotherms. The investigation also involved the use of the Brunauer-Emmett-Teller equation and the Dubinin-Radushkevich method. The FT-IR results show that the pretreatment promotes the formation of surface oxygen functionalities and leads to an increase of the interplanar distance ($d_{002}$) of the functional groups induced between carbon layers. Moreover, the specific surface area of the pitch-based ACs increases in proportion to the amount of $KMnO_4$ pretreatment and reaches its highest value of 2334 $m^2$/g with 2 g of $KMnO_4$ because the surface oxygen groups of the pitch act as an active site during chemical activation.

• Journal of the Korean Vacuum Society
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• v.22 no.6
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• pp.277-284
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• 2013

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. The Ni layer on the $SiO_2$ substrate was used as a catalyst for the formation of the carbon coils. The characteristics (formation densities, morphologies, and geometries) of the as-grown carbon coils on the substrate with or without the $H_2$ plasma pretreatment process were investigated. By the relatively short time (1 minute) $H_2$ plasma pretreatment on the Ni catalyst layered-substrate prior to the carbon coils synthesis reaction, the dominant formation of the carbon microcoils on the substrate could be achieved. After the relatively long time (30 minutes) $H_2$ plasma pretreatment process, on the other hand, we could obtain the noble-shaped geometrical nanostructures, namely the formation of the numerous carbon nanocoils along the growth of the carbon microcoils. This noble-shaped geometrical nanostructure seemed to play a promising role as the good catalyst support for holding the very tiny Ni catalyst grains.

• Journal of Industrial Technology
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• v.39 no.1
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• pp.7-14
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• 2019

Carbon nanotubes (CNT) on metal substrates are definitely beneficial because they can maintain robust mechanical stability and high conductivity between CNT and metal interfaces. Here, we report direct growth of CNT on Ni-based superalloy, Inconel 600, using thermal chemical vapor deposition (CVD) with acetylene feedstock in the growth temperature range of $400-725^{\circ}C$. Furthermore, we studied the effect of substrate pretreatment on the growth yield enhancement and growth temperature decrease of CNT on Inconel 600. Activation energy (AE) for CNT growth was estimated from the CNT height change with respect to the growth temperature. The AE values significantly decreased from 205.03 to 24.35 kJ/mol by the pretreatment of thermal oxidation of Inconel substrate at $725^{\circ}C$ under ambient. Higher oxidation temperature tends to have lower activation energy. The results have shown the importance of pretreatment temperature on CNT growth yield and growth temperature decrease.

• Clean Technology
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• v.30 no.2
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• pp.145-156
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• 2024

Carbon has a large specific area and excellent chemical stability, so research on its use as a catalyst support is actively conducted. When using carbon as a support, the pretreatment process is essential. Through pretreatment of carbon, the growth of metal nanoparticles can be controlled and the bonding strength between the support and metal particles can be improved. In this study, carbon was pretreated for surface modification and 5 wt% Pd/C catalysts were synthesized using it as a support. Catalytic activity was evaluated through phenol hydrogenation. To compare with nitric acid, which is commonly used in carbon pretreatment, carbon pretreatment was performed using organic acid. Pd/C treated with gluconic acid showed the highest activity, with 94.93% phenol conversion and 92.76% cyclohexanone selectivity. Therefore, it is expected that pretreatment of the carbon support using organic acid will not only overcome the disadvantages of inorganic acid treatment but also improve catalyst performance.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.110-116
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• 2016

Biogas yields point of view, the possibility of reusing excess sludge treated by thermal pretreatment for the purpose of improving the efficiency of the anaerobic digestion process has been investigated in recent year. Thermal pretreatment technology was considered as a pretreatment technique to improve excess sludge properties because of the solubilization of particulate organics. As a view point of sludge reduction and recycle, however, many researchers focused on the ability of particulate hydrolysis and COD solubilization under a high temperature, and few reports have addressed on the physical/chemical characteristics changing. This research was performed to evaluate the effects of a various temperature and chemical additives on carbon formation and fractionation in treated slurry from thermal pretreatment. Based on the results, it was revealed that oxidants injection and temperature changing have significantly caused the change of carbon fractions in slurry from thermal pretreament. Especially, it was considered that the efficiencies of particle hydrolysis increased with the increase of the reaction temperature. Low molecular weight(Mw < 350 g/mol) organic carbon formation increased with the increase of oxidants injection. It was expected that results of this research will provide an overview of the characteristics of thermal pretreatement for excess sludge reduction and recycle.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.205-209
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• 2003

The various pretreatment processes were evaluated for removal of oil pollutants with weathered oil contaminated seawater in a reverse osmosis desalination process. Weathered oil contaminated seawater was made by biodegradation and photooxidation with oil containing seawater. Coagulation, ultrafiltration, advanced oxidation processes and granular activated carbon filtration was used with pretreatment for dissolved organic carbon. Crude oil was removed but. weathered oil contaminated seawater was not removed by biodegradation and coagulation. DOC and E260 was removed with about 20 % and 40 % by membrane filter of cut off molecular weight 500. So, the most of dissolved organic carbon in weathered oil contaminated seawater was revealed that molecular weight was lower than 500. It is difficult to remove DOC in weathered oil contaminated seawater by advanced oxidation processes treatment, but, E260 was removed more high. However, DOC in weathered oil contaminated seawater was easily adsorbed to GAC. It is revealed that DOC was removed by adsorption.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.1
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• pp.25-36
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• 2022

To identify the effect and mechanism of carbon monoxide (CO) on delayed rectifier K⁺ currents (I_K) of human cardiac fibroblasts (HCFs), we used the wholecell mode patch-clamp technique. Application of CO delivered by carbon monoxidereleasing molecule-3 (CORM3) increased the amplitude of outward K⁺ currents, and diphenyl phosphine oxide-1 (a specific I_K blocker) inhibited the currents. CORM3-induced augmentation was blocked by pretreatment with nitric oxide synthase blockers (L-NG-monomethyl arginine citrate and L-NG-nitro arginine methyl ester). Pretreatment with KT5823 (a protein kinas G blocker), 1H-[1,-2,-4] oxadiazolo-[4,-3-a] quinoxalin-1-on (ODQ, a soluble guanylate cyclase blocker), KT5720 (a protein kinase A blocker), and SQ22536 (an adenylate cyclase blocker) blocked the CORM3 stimulating effect on I_K. In addition, pretreatment with SB239063 (a p38 mitogen-activated protein kinase [MAPK] blocker) and PD98059 (a p44/42 MAPK blocker) also blocked the CORM3's effect on the currents. When testing the involvement of S-nitrosylation, pretreatment of N-ethylmaleimide (a thiol-alkylating reagent) blocked CO-induced I_K activation and DL-dithiothreitol (a reducing agent) reversed this effect. Pretreatment with 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)-21H,23H porphyrin manganese (III) pentachloride and manganese (III) tetrakis (4-benzoic acid) porphyrin chloride (superoxide dismutase mimetics), diphenyleneiodonium chloride (an NADPH oxidase blocker), or allopurinol (a xanthine oxidase blocker) also inhibited CO-induced I_K activation. These results suggest that CO enhances I_K in HCFs through the nitric oxide, phosphorylation by protein kinase G, protein kinase A, and MAPK, S-nitrosylation and reduction/oxidation (redox) signaling pathways.