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Waste toner with high carbon content has the potential to become a carbon material, but its utilization is limited due to the low carbonization yield.

Cellulose aerogel is used for urea adsorption for the first time, and displays a fast adsorption rate and high adsorption capacity.

A rapid and efficient synthesis strategy of MgAl-LDH was proposed. MgAl-LDH with high specific surface area was synthesized in situ by using η-Al2O3 as carrier, and the synthesis time was greatly shortened by both increasing temperature and introducing ethanol as co-solvent. Besides, the growth process of MgAl-LDH on the surface of η-Al2O3 is also revealed. Under optimized conditions, the specific surface area of the MgAl-LDH is as high as 172.4 m2/g, the crystalline size is as small as 12.82 nm, and the basicity can reach 1.795 mmol/g. The urea wastewater was degraded from 8000 mg/L to 6.85 mg/L over the catalyst synthesized by the rapid method, and the catalyst still maintains high activity after four uses. Also, it was found that there is a good linear relationship between the urea removal rate and the basicity of MgAl-LDH.

Coal tar light oil (CTLO), an unclean byproduct of coal chemical industry, is a potential material for the manufacture of high-octane gasoline blending component. CoMo/η-Al2O3, a catalyst with lower desulfurization performance but less octane loss, is selected from four catalysts to further reduce sulfur content of CTLO by phosphorus modification. Catalysts modified by various content of phosphorus are characterized by a series of methods. The results show that addition of appropriate amount of phosphorus can improve the structure and acidity of catalysts, and weaken the interaction between active component and carrier. Furthermore, most of naphthalene in CTLO is converted into tetralin with 1.5 wt% phosphorus loading, and tetralin can play an important role of hydrogen transfer during catalytic hydrogenation process, which promotes the removal of heteroatom compounds. When the loading of phosphorus is 1.5 wt%, the content of S , N heteroatom compounds is only 7.2 mg/kg, 0.021% in product oil respectively, which is beneficial to reduce automobile emissions. Meanwhile, the RON reaches 105.3, and only decreases by 2.2 units compared to the original CTLO. Product oil catalyzed by CoMoP1.5/η-Al2O3 can be used as excellent high-octane gasoline blending component with low sulfur.

For a fixed bed gasifier, coal gas is mainly derived from dry distillation zone and gasification zone. The upstream gas from gasification zone will inevitably affect the composition and production of dry distillation gas. Therefore, the composition of upstream gas and the reaction conditions of dry distillation zone were simulated to perform experiments of Yining coal pyrolysis under a series of atmospheres. Some new discoveries are obtained. H2O and the hydrogen-containing gas have a significant impact on the release of dry distillation gas. H2O inhibits the release of CO, CO2 and CH4, but promotes the release of H2 which is not from char−H2O gasification. When the hydrogen-containing gas passes through dry distillation zone, the path of stabilizing radicals is completely changed, resulting in that coal pyrolysis changes from a process of generating H2 under inert atmosphere to a process of consuming a large amount of H2. In addition, water gas shift reaction is the only homogeneous reaction observed obviously in dry distillation zone, which can promote the production increase of CO2, but can not prevent the production decrease of H2 in coal gas.

MnO2 was screened from various metal oxides and different crystal structures of MnO2 were prepared, which were used to hydrolyze urea process wastewater for energy conservation and environmental protection. The characterizations of XRD, SEM, Raman, FT-IR, XPS and H2-TPR were employed and the hydrolysis experiments were carried out, demonstrating that oxygen vacancy on the surface of MnO2 might be the catalytic activity source on urea hydrolysis. By optimizing reaction influencing factors, the residual urea concentration reduced to 1.61 mg/L over α-MnO2, far below the effluent standard. Meanwhile, the temperature of heterogeneous hydrolysis over α-MnO2 dropped drastically compared with that of thermal hydrolysis. Further, the kinetic parameters of hydrolysis were obtained over α-MnO2. And α-MnO2 also showed excellent recycling ability on the reused test.

High value-added utilization of plastic waste has historically been a problem, which has driven researchers to make long-term and unremitting efforts to tackle it. High-performance carbon based solid acid (CSA) was prepared from polyvinyl chloride (PVC) and polyethylene (PE) in different proportions. The small amount of chlorine is still residual on the edge of graphitic carbon sheets after co-carbonization and sulfonation. Strong electronegative –Cl group and the high-density phenolic –OH group, double-adsorption group, are covalently bonded to the edges of the graphitic carbon sheets, contributing to the decrystallization of cellulose to a large extent. Meanwhile, PVC and PE-derived CSAs have significantly higher –SO3H group density than PVC-derived CSA and cellulose-derived CSA. These are obviously beneficial to the improvement of hydrolysis activity, which can be attributed to structural optimization caused by co-carbonization PVC and PE. The CSA with a mixture of 80% proportions has great catalytic activity and repeatability.

(1) Background: The housing environment is crucial to the health of older Chinese people and is becoming an urgent policy initiative. This study explores factors that facilitate or impede the adoption of policy innovation on major housing adaptation (HA) by Chinese provincial governments using the framework of policy innovation and diffusion theory. (2) Methods: This study constructs an event history dataset on HA policy related to elevator retrofitting in existing multifamily dwellings in China; the lack of elevators constitutes an insurmountable barrier in older adults’ daily lives in China. The hypotheses were tested by using a traditional event history analysis (EHA) model and a piecewise constant exponential (PCE) model, which is a modified EHA model. The dataset was summarized as “province-year” event history data on 30 Chinese provinces from 2008 to 2019. (3) Results: In addition to internal determinants (e.g., population aging level and financial dependency), diffusion mechanisms can significantly facilitate or impede the adoption of major HA policy innovation by provincial governments. Policy adoption by neighboring governments helps facilitate policy adoption by nonadopters, but policy adoption by subordinate city governments impedes provincial governments’ adoption of major HA policy innovation. (4) Conclusions: This study concludes that provincial governments’ adoption of major HA policy innovation should be given a higher policy priority. The central government can promote provincial governments’ adoption of major HA that primarily benefits older adults by using fiscal transfer payments and enhancing the legitimacy of such policy.

Magnesium aluminum layered double hydroxide (MgAl–LDH) was first successfully deposited in situ on η-Al2O3 applied to catalyze urea hydrolysis. Characterization by AAS, XRD, SEM, EDS, DSC, FT-IR, N2-BET, determination of base strength and basicity and experiments on hydrolysis activities of in situ MgAl–LDH catalysts show that the crystallinity and coverage degree of MgAl–LDH on η-Al2O3 gradually increase with increasing initial c(Mg2+). When initial c(Mg2+) = 2 mol L−1, η-Al2O3 is completely covered and the smallest particle size, the highest crystallinity, basicity and urea degradation rate of in situ MgAl–LDH are obtained. The basicity is mainly from Mg–OH at the edges of MgAl–LDH on η-Al2O3. The highest basicity corresponds to the highest urea degradation rate, Mg–OH is the active sites for catalytic hydrolysis of urea. The specific surface area, basicity and catalytic activity of MgAl–LDH by in situ synthesis are evidently higher than MgO and MgAl–LDH purchased. The urea concentration is 8.162 mg L−1 at 165 °C after 120 min with in situ MgAl–LDH (c(Mg2+) = 2 mol L−1) as catalyst, which is below the effluent standard. In situ MgAl–LDH also shows excellent recycling ability and the slight loss of activity should be due to the reduction of basicity, which is caused by hydrothermal conditions. In addition, a possible catalytic mechanism of urea hydrolysis over MgAl–LDH is proposed.

Carbon based solid acids (CSAs) were prepared from cellulose and lignin at different carbonization temperatures and applied to hydrolysis of cellulose, which is of great significance for the multiple utilization of biomass. The structure and performance of cellulose based solid acids (CCSAs) and lignin based solid acids (LCSAs) were investigated by TG-DTG, XRD, FT-IR, XPS, elemental analysis, titration methods, etc. And immersion enthalpy was introduced into estimating the hydrophilicity of CSAs. The results show that the optimum carbonization temperature varies for raw material, and the optimum carbonization temperatures of cellulose and lignin are 683 and 653 K respectively. The adsorption capacities of CCSAs and LCSAs may not only be related to phenolic OH density, but may also relate to alkyl side chains and aromatic frameworks. Compared with LCSAs, the CCSAs possess higher immersion enthalpy, indicating that the CCSAs are more easily accessible to substrate, which contributes to hydrolysis. The hydrolysis activities of CCSAs are always higher than those of LCSAs, which may be due to a higher –SO3H groups densities and better accessibility between substrate and acid sites for CCSAs. These are determined by a big difference in the chemical composition between cellulose and lignin.

A series of carbon-based solid acids (CSAs) were respectively prepared by the different relative proportions of cellulose and lignin to simulate biomass, and employed to hydrolyze cellulose. The influence of relative proportions of cellulose and lignin on mixture-derived CSA (MCSA) has been investigated in detail. Differences in the structure and performance of MCSAs were found to be obvious. The microcrystalline structure parameters, adsorption capability and hydrolysis activity of MCSA present regular variation trend with the increase of cellulose proportions, which can be attributed to the interaction of cellulose and lignin during co-carbonization. When cellulose proportion is 50%, the co-carbonization is at a turning point, the carbon skeleton of MCSA is more flexible and disordered with larger interlamellar spacing and more C O C bond. Meanwhile, MCSA exhibits remarkable adsorption capability, and the hydrolysis activity is comparable to that of cellulose-derived CSA.

Raw Gas generated from LCPG (lump coal pressurized gasifier) contains quantities of organics including methane so that it is not suitable as syngas. A process was proposed to solve this problem, and Aspen Plus was used to discuss its possibility that Raw Gas was reformed to clean syngas through introducing oxygen on the principle of thermodynamic equilibrium. The simulation results reveal that almost all organics are completely converted to simple substances such as hydrogen and carbon monoxide whether or not to preheat. Raw Syngas and wastewater no longer contain various organic pollutants eliminated difficultly besides very small amounts of ammonia and hydrogen sulfide, which certainly simplifies the purification and post-treatment processes. A Raw Syngas with H 2 /CO ratio of 2.0 was attained under the operating condition of 2.35 Mpa and 918 °C. Such H 2 /CO ratio is higher than those of coal gas derived from existing gasification technologies. Meanwhile, the total yield and content of the effective gas (CO + H 2 ) have been increased to 1109 m 3 /t and 72.0% respectively in the preheating process, and GE (gasification efficiency) rises to 84.8%. The OC (oxygen consumption), CC (coal consumption) and SC (steam consumption) have been reduced by 47.3%, 50.7% and 49.4% respectively compared with LCPG. In addition, the feasibility of this process was further verified with kinetic simulation.

Pyrolysis techniques can provide a way to convert polyvinyl chloride (PVC) waste into high value liquids and gases. The inexpensive pyrolysis residue was used to successfully prepare a carbon-based solid acid (CSA) bearing –Cl functional group by a simple process, which has been shown to be highly effective for hydrolyzing microcrystalline cellulose into reducing sugars. The structure, acidic functional group density and catalytic activity of PVC-derived CSA (PCSA) were investigated. The results showed that the carbonization time has an important influence on the structure and properties of the PCSA, especially in a lower temperature range. There was a compensation effect between the carbonization temperature and time on the structure and the activity of PCSA. Phenolic-OH and –Cl groups acted as double cellulose-binding sites and together improved the adsorbability of PCSA, which is much higher than that of traditional CSA and other CSAs bearing –Cl groups. The high hydrolytic activity was determined by the adequate density of the –SO3H group, the excellent adsorption property, and the entire structure of the PCSA.

China&rsquo, s Serious Disease Insurance Scheme (SDIS) was set up to relieve the financial burdens on serious disease patients. It is a crucial part of the national basic medical insurance scheme, which is regarded as one of the largest government-funded social security programs in the world. The most significant institutional innovation of the SDIS is that the approach of a public&ndash, private partnership (PPP) is applied in an attempt to facilitate the efficiency of its implementation. The objective of this paper is to evaluate the implementation of the SDIS in China through PPPs, and to identify the problems to be tackled if the Chinese government intends to make such a plan work better for the majority of urban and rural residents. With the effective support from local officials and practitioners, the authors of this paper collected copies of SDIS contracts of multiple cities in Guangdong, one of the most developed provinces of China. Guided by a research framework drawn from the PPP literature, details of contract enforcement were also examined. The authors discovered that the role of local states is rather dominant, they have manipulated contract drafting and implementation. Additionally, current mechanisms for profit sharing, risk sharing, and information exchange have placed insurance companies in a rather disadvantageous situation. To achieve the sustainable development of the SDIS, the authors suggest that a further reform on implementation of a PPP must be pushed forward.

A carbon-based solid acid (CSA) was prepared from phenolic residue which is the solid waste generated from the refining of crude phenol. Influence of various reaction conditions on hydrolysis of cellulose over phenolic residue-derived solid acid (PRCSA) is discussed. The results indicate that both cellulose hydrolysis and the effectiveness of PRCSA need a suitable temperature range. The glucose can be adsorbed on the surface of PRCSA due to the hydroxyl-rich structure of PRCSA. The behavior of generated glucose in competitive adsorption with unreacted cellulose on PRCSA suppresses the continuing hydrolysis of cellulose to some extent. For PRCSA, the number of effective active sites increases with the decrease of catalyst particle size. In heterogeneous hydrolysis of cellulose assisted by inorganic salts, the promotion of KCl and NaCl is remarkable, which is attributed to the decrystallization of chloride ions on cellulose and the ion exchange between cations and H + in –SO 3 H bonded to PRCSA.

A novel carbon-based solid acid was successfully prepared by sulfonation of cocarbonized starch and polyvinyl chloride (PVC). The characterization results show that this catalyst possesses all characteristics of traditional carbon-based solid acids (CSAs). The differences are that chlorine from PVC is covalently bonded to edges of aromatic carbon sheets as new active groups, and ether (C–O–C) and aliphatic (–CH2–) bridges are formed during the cocarbonization process which are derived from oxygen in starch and alkyl in PVC, respectively. Chlorine groups can adsorb cellulose hydroxyl groups strongly and bridge bonds make the carbon framework fully stretch, which reduces hindrance between SO3H groups and glycosidic bonds to promote the catalytic performance in cellulose hydrolysis experiments. Furthermore, the durability results indicate that this catalyst has good stability.

Carbon-based solid acid (CSA) was successfully prepared using phenolic residue as starting material. The characterization results indicate that such solid acid catalyst mainly consists of four building blocks: the condensed aromatic carbon sheets, the active groups (including SO3H, COOH and phenolic OH), the side chains (including CH3 and OCH3) and the bridge linkages (including O , CH2 , CH2 CH2 , and OCH2 ) acting as the intermediates between aromatic clusters. Most of these building blocks, except for the SO3H, could be derived from the corresponding part of the phenolic residue. Aliphatic side chains have been demonstrated to greatly improve the sulfonation activity of carbon precursor and promote the catalytic performance in cellulose hydrolysis, and the carbon-based catalyst sulfonated for just 1 h could exhibit almost similar catalytic activity compared with the catalyst sulfonated for a longer time. However, their hydrophobicity and steric hindrance reduced the utilization efficiency of the sulfonic acid groups to a certain extent.

In order to find an effective method for treating urea wastewater, the experiments on the hydrolysis of urea in wastewater were conducted in a fixed bed reactor with different aluminas (α-Al2O3, γ-Al2O3, and η-Al2O3) as catalysts respectively in contrast with inert ceramic particle. The results indicate that the three alumina catalysts show obvious catalytic activity for urea hydrolysis at 125 °C. The order of activity is η-Al2O3 > γ-Al2O3 > α-Al2O3, and the activity difference increases with increasing temperature. According to the characterization results, surface acidity has little impact on the activity of catalyst. However, it was found that surface basicity of alumina catalyst plays an important role in catalytic hydrolysis of urea, and the activity of catalyst may be also influenced by the basic strength. With η-Al2O3 as catalyst, the urea concentration in wastewater is reduced to 4.96 mg/L at a temperature of 165 °C. Moreover, the η-Al2O3 shows a good stability for urea hydrolysis. The hydrolysis of urea over η-Al2O3 catalyst can evidently reduce the reaction temperature and is promising to replace industrial thermal hydrolysis process.

In soap-free latex media, poly(styrene-methyl methacrylate)/MCM-41 core/shell composite microspheres have been fabricated by adding silicate source in batches. In this process, silicate species and the surfactant micelles were self-assembled into 2-dimensional hexagonal arrangement on the surface of P(St-MMA) microspheres. Hollow MCM-41 microspheres were obtained via removing polymer core by solvent. XRD, TEM, IR and N2 adsorption–desorption analysis were applied to characterize products. The results showed that average diameter and wall thickness of hollow MCM-41 microspheres is about 240 nm and 20 nm, respectively. Results of N2 adsorption–desorption indicate that hollow MCM-41 microspheres possess a highly ordered mesoporous structure and a narrow pore distribution with a mean value of 2.34 nm.