FUEL
·
2022
·
IF 8.035
You Qi,Luming Zhang,Shiyuan Zhang,Qiufeng Cao,Fengjie Guo,Zhaohui Wang,Qing Cao
With pyrolytic bio-oil as raw material, an efficient bio-oil-based dispersant (BOBD) applied to coal water slurry (CWS) has been synthesized successfully by grafting polymerization of the organic fractions from the bio-oil and acrylic acid (AA) in the mild condition. As a comparison, two commercial dispersants, namely poly (styrene sulfonic acid) sodium (PSS) and sodium lignosulfonate (SL) were employed. The structures and properties of the synthesized BOBD were characterized by using FTIR, 1 H NMR, GC/MS, GPC, zeta potential, contact angle, and surface tension. The results showed the molecular weight of the BOBD was concentrated at 832 g/mol and 1954 g/mol. The surface tension and contact angle of BOBD aqueous solution were 47.71 mN/m −1 and 60.8° respectively. The zeta potential of the suspension prepared from BOBD-water-coal was −67.1 mV. Using BOBD as a dispersant, the apparent viscosity of CWS loading 66 wt% coal dropped to 288 mPa·s at 0.3 wt% BOBD, and the maximum coal content reached 72 wt%. BOBD exhibited better viscosity reduction and stability enhancement capabilities than PSS and SL. The excellent dispersion performance of BOBD was due to the large electrostatic repulsion and steric hindrance derived from the grafted acrylic polymer, which effectively dispersed the coal particles uniformly. The rheological behavior of CWS with BOBD belonged to pseudoplastic fluid. The synthesized BOBD not only had an excellent dispersion performance but also could overcome the shortcomings of secondary pollution caused by PSS and SL containing element sulfur as dispersants in combustion. In addition, the synthetic route possessed simple, environmentally friendly and sustainable characteristics. The research opened up a new way for the utilization of bio-oil.
研究领域:
能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2023
·
IF 2.2
Lun Du,Guanghua Zhang,Shining Hu,Jie Luo,Wanbin Zhang,Ce Zhang,Junguo Li,Junfeng Zhu
The hydrophilic surface and developed pore structure restricted the application of abundant low rank coals (LRC) for the preparation of coal water slurry (CWS) with high concentration. In this work, emulsified asphalt was applied as an effective and low cost modifier to modify coal surface and improve the slurry making performance of LRC. The successful modification was verified by various technologies, such as chemical titration, X-ray photoelectron spectroscopy (XPS) and Zeta potential measurements. The results revealed that the oxygen containing groups located at LRC surface were covered by emulsified asphalt, which further caused the decrease of Zeta potential. The influence of modification on wettability of coal was also evaluated by contact angle and moisture re-adsorption. It showed that the hydrophobicity of LRC significantly increased, which is accompanied with the reduction of inherent moisture. Besides, the results of nitrogen adsorption and scanning electron microscope (SEM) verified that the hydrophobic layer formed by emulsified asphalt blocked the pores of LRC. The modified LRC also exhibited better adsorption ability to the widely used anionic dispersant naphthalene sulfonate formaldehyde condensate (NSF) than that of raw coal (RC) and microwave dehydration coal (MDC). Anyhow, modified LRC possessed the characteristics as high rank coal. Afterwards, modified coal was applied to prepare CWS. The results showed that CWS prepared by modified LRC exhibited superior slurry making performance as compared to RC and MDC. The surface modification reduced the inherent moisture and promoted the adsorption of dispersant, which increased the free water amount and enhanced electrostatic repulsion and steric hindrance among coal particles. Accordingly, the maximum concentration for CWS increased, and the static stability enhanced.
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Xiaofang You,Wenqi Zhang,Xiaoteng Li,Chuandong Ma,Zhisen Li,Qingbiao Wang,Zhenhua Wang,Lin Li
In this study, alkali-modified municipal sludge (AS) was mixed with low-rank coal to prepare AS-coal water slurry (ASCWS). The influence of AS on the slurrying performance of coal water slurry (CWS) was investigated, and the slurrying mechanism of municipal sludge-CWS (SCWS) was elucidated. Research on the alkali modification of municipal sludge showed that the effectiveness of the modifiers was in the order Ca(OH) 2 > NaOH > KOH > K 2 CO 3 . Considering the apparent viscosity of the slurry as the evaluation criterion, the optimal alkali modification scheme was determined through the response surface optimization test, and 19.99 % Ca(OH) 2 was suitable to modify the sludge for 14.61 h Compared with the unmodified sludge, the content of oxygen-containing functional groups on the surface of AS was reduced, and the flocculent structure was disrupted, which helped improve the slurry formation performance of the SCWS. Blending the sludge with the CWS enhanced the stability of the slurry, and the water separation rates for the SCWS and ASCWS decreased from 18.62 % to 5.00 % and 5.26 %, respectively. The mechanism study showed that the zeta potential values of SCWS and ASCWS decreased from −10.67 mV to –32.23 mV and −39.22 mV, respectively. The increased electronegativity of the slurry owing to the addition of sludge facilitated particle dispersion and enhanced slurry stability. The adsorption patterns of sodium poly[(naphthaleneformaldehyde)sulfonate] (MF) on coal, sludge, and modified sludge were consistent with the Langmuir adsorption model. The pseudo-second-order kinetic model accurately described the adsorption process of MF on coal, sludge, and modified sludge.
研究领域:
能源科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Chuandong Ma,Wenqi Zhang,Zhisen Li,Junxiang Wang,Qingbiao Wang,Lin Li,Xiaofang You
In this study, high-concentration inorganic salt wastewater containing microplastics (MPs) was used to prepare MPs-coal wastewater slurry (MPs-CWWS). The rheological behavior, stability, and solid content of the slurry were discussed, and the interfacial interaction mechanism between particles was analyzed. Experimental results show that the presence of inorganic salts in the system will cause an increase in viscosity. This is because cations neutralize the negative charges on particle, resulting in a reduction in the electrostatic repulsion between particles. In addition, a large amount of water is adsorbed due to “ionic bonding”, resulting in a reduction in free water content and therefore a decrease in the solid loading of the suspended system. The enhanced stability is attributed to the thickening of the hydrated film. MPs have strong hydrophobicity and are easy to adsorb dispersants due to non-polar effects, which increases the negative charge and steric hindrance effect on the surface. MPs promote the dispersion of particles in the slurry. The extended-DLVO theoretical calculation results show that electrostatic repulsion and steric hindrance effect are the main forces promoting particle dispersion. Electrostatic repulsion plays a key role in promoting particle dispersion. The extended-DLVO theoretical calculations verify that the main reason for the increase in viscosity caused by inorganic salts is the decrease in electrostatic interaction energy. The existence of MPs can reduce the negative effects caused by inorganic salts.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Kang Zhang,Jianzhong Ma,Bin Lyu,Guoxin Shi,Bo Zhou,Yu Tian
Three kinds of jellyfish-like three-dimensional dispersants with different “tentacle structures” were designed and synthesized via polymerization reaction of tannic acid (TA) with starch, allyl polyoxyethylene ether 1200 (APEG1200), and acrylic acid (AA), respectively. These dispersants were employed for preparing high-concentrated coal–water slurry (CWS). Their structures and surfactivity were characterized using FTIR, 1 H NMR and surface tension. The effects of the TA-based dispersants on the performance of CWS were fundamentally investigated. The TA-based dispersant with starch as the “tentacle structure” (TA-St) exhibited the better viscosity-reducing and stabilizing capability for CWS than those with APEG1200 (TA-APEG) or AA (TAA). The apparent viscosity reduced to 317 mPa·s at 0.5 wt% TA-St, and the maximum coal content exceeded 71 wt%. Rheological experiments showed that the CWS prepared with the three TA-based dispersants behaved as pseudoplastic fluids, and the CWS with TA-St presented the smallest yield stress. After 3.5 days of storage, the separated water ratio of CWS with TA-St reached 4.15 wt%. Meanwhile, the TA-St dispersant showed a better effect in increasing the adsorption capacity and adsorption film thickness, wettability, and absolute value of zeta potential of the coal surface compared with TAA and TA-APEG. The saturated adsorption quantity of TA-St on the coal surface was 1.77 mg/g. The excellent performances of TA-St in dispersing and stabilizing coal particles in CWS were due to the great steric hindrance and electrostatic repulsion effect derived from the starch “tentacle structure”, which effectively reduced the aggregation among coal particles.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Royal Society Open Science
·
2021
·Vol. 8
·期 1
·
IF 2.963
Lun Du,Guanghua Zhang,Dongdong Yang,Jie Luo,Yewei Liu,Wanbin Zhang,Ce Zhang,Junguo Li,Junfeng Zhu
In this work, a novel amphoteric copolymer named Poly(sodium p-styrenesulfonate–co-acrylic acid-co-diallyldimethylammonium chloride) (P(SS-co-AA-co-DMDAAC)) was synthesized via free radical polymerization. Afterwards, P(SS-co-AA-co-DMDAAC) was explored for use as a dispersant in coal water slurry (CWS) preparation. The structure of P(SS-co-AA-co-DMDAAC) was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The synthetic conditions were optimized as the feed ratio of AA to SS was 1 : 1 (for Yulin coal) or 1.5 : 1 (for Yili coal), and DMDAAC dosage was 4.0 wt% (for Yulin coal) and 6.0 wt% (for Yili coal) toward total monomers. The performances of P(SS-co-AA-co-DMDAAC) as a dispersant for CWS were evaluated by various technologies, such as apparent viscosity, zeta potential, static stability and contact angle measurements. The results revealed that the optimized dosage of P(SS-co-AA-co-DMDAAC) in CWS preparation was 0.3 and 0.4 wt% for Yulin coal and Yili coal respectively. In this optimum condition, CWS prepared using P(SS-co-AA-co-DMDAAC) as dispersant showed a typical shear thinning behaviour and excellent stability, which are desired in industries. The rheological models also confirmed the pseudo-plastic characteristics of CWS. Finally, compared with the widely used anionic dispersant naphthalene sulphonate formaldehyde condensate (NSF) and poly(sodium p-styrenesulfonate) (PSS), P(SS-co-AA-co-DMDAAC) developed in this work exhibited better slurry making performance. The introduction of cationic functional groups promoted the adsorption of the dispersant, which further enhanced the electrostatic repulsion and steric hindrance among coal particles. Accordingly, the viscosity of CWS decreased and static stability enhanced.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Water Research & Technology
·
2019
·Vol. 5
·期 10
·1736-1747
·
IF 4.195
Chuanchuan Cui,Shuguang Zhang
In order to control the formation of inorganic calcium scale and improve the environmental benefits of coal water slurry, a non-phosphorus-containing and multipurpose copolymer IA–AMPS–APEG was successfully prepared. The chemical structure, molecular weight and thermal stability of the copolymer were characterized by FTIR, GPC and TGA. FTIR confirmed that the structure of the copolymer was consistent with the expected structure. The results of GPC and TGA showed that the copolymer's number average molecular weight was 31 870, and it had excellent thermal stability. The scale inhibition performance of the copolymer was investigated to determine the optimal synthesis conditions: n(IA) : n(AMPS) : n(APEG) = 1 : 2 : 0.33, the dosage of initiator is 4% of the total mass of the monomers, and the reaction temperature and time were optimized to 80 °C and 4 hours, respectively. The maximum scale inhibition efficiencies against CaCO3 and CaSO4 scale deposits were 94.35% (24 mg L−1) and 85.69% (22 mg L−1). Morphologies and crystal structures of the scale deposits were studied with SEM, TEM and XRD techniques. The results demonstrated that the surface morphologies and crystal structures of the inorganic scale deposits were significantly destroyed by the copolymer. In addition, the prepared coal water slurry using IA–AMPS–APEG as a dispersing additive had a high concentration, low viscosity, and good fluidity and stability. In short, the novel and multifunctional copolymer in this work is considered to be an increasingly promising candidate not only as a scale inhibitor in cooling water and reverse osmosis systems but also as a dispersant used in the preparation of coal water slurry.
研究领域:
环境科学
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 55
·35508-35516
·
IF 4.036
Wenlin Shuai,Shiwei Wang,Taotao Sun,Hongfeng Yin,Yu Zu,Gang Yao,Zhonghua Li,Zhaokun Qi,Mei Zhong
Dispersants can have a substantial impact on the rheological characteristics of coal–water slurry (CWS). Due to their advantages in cost and synthesis, linear dispersants are currently most often employed in the commercial manufacturing of CWS. However, this kind of dispersant gives limited performance because of its weak adsorption and steric hindrance effect on the coal–water interface. This work describes a new linear dispersant (PSAF) with a significant steric hindrance effect that was created by incorporating phenolic groups into its molecular architecture, which gives higher maximum coal content (63.79 wt%) than that (63.11 wt%) from sulfonated acetone–formaldehyde (SAF). The synthesis mechanism was investigated using GPC, FT-IR and NMR. Various technologies were used to explore the rheological characteristics and dispersion mechanism for CWS prepared with PSAF. PSAF as well as SAF showed monolayer adsorption on the surface of coal and displayed a higher adsorption layer thickness (3.5 nm). PSAF dispersant presents stand-up adsorption rather than lie-down adsorption of SAF because of its strong π–π action, resulting in a stronger steric hindrance effect and improved rheological performance. This work can provide guidelines for the development of a high-performance dispersant as well as an understanding of the dispersal process for CWS.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2024
·Vol. 17
·期 1
·21
·
IF 4.7
Guanghua Zhang,Ruijun Liu,Wanbin Zhang,Kangmin Zhang,Junfeng Zhu,Ce Zhang
This study introduces a novel water-insoluble dispersant for coal water slurry (CWS), namely, a poly(sodium styrene sulfonate)-graftedSiO2nanoparticle (SiO2-g-PSSNa). SiO2-g-PSSNa was synthesized by combining the surface acylation reaction with surface-initiated atom transfer radical polymerization (SI-ATRP). Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrometer (EDS), nuclear magnetic resonance spectroscopy (NMR) and thermogravimetric analysis (TGA) verified that SiO2-g-PSSNa with the desired structure was successfully obtained. Afterwards, the performance of SiO2-g-PSSNa as a dispersant in CWS preparation was evaluated. The results indicated that the optimal dosage of SiO2-g-PSSNa was 0.3%. Compared to the famous commercial products, PSSNa and lignosulfonate (LS), SiO2-g-PSSNa exhibits improved viscosity reduction performance. When SiO2-g-PSSNa was used as the dispersant, the maximum coal loading of CWS was 64.2%, which was higher than LS (63.4%) and PSSNa (63.9%). All CWSs obtained in this study were pseudoplastic fluids and more consistent with the Herschel–Bulkley rheological model. The turbiscan stability index (TSI) of CWS prepared with SiO2-g-PSSNa was 0.05, which was significantly lower than CWSs obtained from PSSNa (0.30) and LS (0.36). Therefore, SiO2-g-PSSNa also exhibits excellent stability performance. This result was confirmed by rod penetration tests. The underlying mechanism was also clarified by various measurements, such as contact angle, zeta potential, EDS and low-field nuclear magnetic resonance spectra (low-field NMR). The results reveal that SiO2-g-PSSNa can adsorbed onto the coal surface. SiO2-g-PSSNa possesses a special branched structure, which bears a higher charge density as compared to linear ones with approximate chemical composition. As a result, coal particles adsorbed with SiO2-g-PSSNa exhibit more electronegativity. With the enhancement of the electrostatic repulsive between coal particles, the apparent viscosity was lowered and the static stability was improved. This study demonstrated that solubility in water is not an essential factor in engineering the dispersant. Densely charged groups are probably more important.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Lian Li,Linyan Zhao,Yixi Wang,Jianning Wu,Guihua Meng,Zhiyong Liu,Jianshu Zhang,Baixing Hu,Qihui He,Xuhong Guo
A novel type of large reticulation, three-dimensional structure of a coal–water slurry dispersant was designed and synthesized, which was mainly used to test the Xinjiang Zhundong coal with abundant reserves and poor slurrying performance. The same types of three dispersants (TIA-1, TIA-2, and TIA-3) were made by adjusting the amount of tannic acid (TA). Commercial NDF dispersant is used for comparison. TA molecules were linked into reticulation by a linker (1,6-dibromohexane) and then modified with 2-acrylanmido-2-methylpropanesulfonic acid and itaconic acid on this reticulated structure. The structure of TIA was confirmed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance. The rheology and stability indicated that the optimal amount of this dispersant was 0.1 wt %, and its pulping concentration was increased to 59 wt %. The dispersants of TIA-1, TIA-2, and TIA-3 comparative tests demonstrated that TIA-1 exhibited excellent stability and rheology, reducing the dosage of the dispersant. The experiment showed that the concentration of slurry could reach 59% with the dosage of 0.1%. This is mainly attributed to the excellent large reticulation, three-dimensional structure of TIA-1. This special structure has polar and nonpolar sites that can efficiently coat coal particles and change the interfacial tension effectively between coal and water.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Suqian Gu,Hussein A. Qulatein,Weijue Gao,Pedram Fatehi
Preparing coal water slurry from coal gasification wastewater as gasification/combustion feedstock offers a promising strategy for wastewater management and resource recovery. The primary challenge lies in optimizing slurry formulation to accommodate wastewater as the aqueous medium. This study demonstrated that carboxyalkylated lignin derivatives, i.e., biomass-based aromatic polymers, were effective dispersants for generating coal gasification wastewater slurry (CGWS). The alkyl chain lengths of carboxyalkylated lignin derivatives significantly influenced their molecular characteristics and, consequently, the physicochemical properties of the resulting slurry. Fundamentally, the dispersion performance of lignin derivatives and sodium methylene dinaphthalene sulfonate (NNO), as a commonly used dispersant for the slurry, was different. While NNO promoted dispersion via increasing electrostatic repulsion, the lignin derivatives promoted the slurry formulation primarily via grafting molecular structure. Among the tested lignin derivatives, CPr (carboxybutylated lignin) required the lowest dosage (0.20 wt%) and increased the solid concentration of the slurry from 50.42 wt% (NNO-CGWS) to 52.81 wt% (CPr-CGWS) at an apparent viscosity of 1000 mPa·s, while reducing its pseudo-plasticity. Additionally, lignin derivatives increased the calorific value of CGWS by 0.191 kcal/g using CPr at a dosage of 0.20 wt%. This work establishes carboxyalkylated lignin, particularly CPr, as a highly effective and eco-friendly dispersant for preparing value-added CGWS from industrial wastewater.
研究领域:
环境工程
·
能源化学工程
·
工业废水处理
·
生物质利用
·
胶体与界面化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2016
·
IF 2.835
Ruikun Wang,Zhenghui Zhao,Qianqian Yin,Jianzhong Liu
The great emission of sewage sludge (hereafter referred to as sludge) has become a serious constraint for the sustainable development of cities. As a solution, mixing sludge into coal water slurry is an economical and feasible way to recycle sludge. The application of this method addresses the difficulty of sludge disposal resulting from high water content and facilitates the effective use of the energy contained in sludge. In the present study, a low-temperature thermal-alkaline (LTTA) method was employed to pretreat sludge. The macromolecular organic substances in the sludge flocs were degraded, and the shearing resistance of the sludge was weakened, thereby improving the co-slurrying ability of the sludge and coal. The sludge showed significant degradation within 1 h of the LTTA treatment. The degradation degree of chemical oxygen demand reached 7.87%, 10.92%, and 49.29% under neutral, Ca(OH)2, and NaOH conditions at 90 °C, respectively. Compared with the original sludge that featured a shearing energy consumption per unit volume (WV) of 35.40 × 104 J/m3, the treated sludge exhibited a decreased WV, which reached 7.19 × 104 and 3.68 × 104 J/m3 after treatment in 90 °C Ca(OH)2 and 90 °C NaOH for 1 h, respectively. Consequently, slurry viscosity decreased to 974.9 and 712.5 mPa·s when the sludge was mixed with coal to prepare the coal sludge slurry (CSS). By contrast, the slurry viscosity of CSS made of the original sludge was 1663.6 mPa·s. A low slurry viscosity is conducive to application processes for CSS, including mixing, transportation, and atomization. The LTTA method can be developed using industrial waste heat and low-cost alkali reagents; therefore, its operating cost is low.
研究领域:
环境工程
·
废物管理
·
能源回收
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）