CN110961087B - PX adsorbent and preparation method thereof - Google Patents
PX adsorbent and preparation method thereof Download PDFInfo
- Publication number
- CN110961087B CN110961087B CN201911174660.0A CN201911174660A CN110961087B CN 110961087 B CN110961087 B CN 110961087B CN 201911174660 A CN201911174660 A CN 201911174660A CN 110961087 B CN110961087 B CN 110961087B
- Authority
- CN
- China
- Prior art keywords
- adsorbent
- crab
- temperature
- crab shell
- hydrochloric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28002—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their physical properties
- B01J20/28011—Other properties, e.g. density, crush strength
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/20—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28057—Surface area, e.g. B.E.T specific surface area
- B01J20/28066—Surface area, e.g. B.E.T specific surface area being more than 1000 m2/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28069—Pore volume, e.g. total pore volume, mesopore volume, micropore volume
- B01J20/28076—Pore volume, e.g. total pore volume, mesopore volume, micropore volume being more than 1.0 ml/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28078—Pore diameter
- B01J20/2808—Pore diameter being less than 2 nm, i.e. micropores or nanopores
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28078—Pore diameter
- B01J20/28083—Pore diameter being in the range 2-50 nm, i.e. mesopores
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/40—Aspects relating to the composition of sorbent or filter aid materials
- B01J2220/48—Sorbents characterised by the starting material used for their preparation
- B01J2220/4875—Sorbents characterised by the starting material used for their preparation the starting material being a waste, residue or of undefined composition
- B01J2220/4881—Residues from shells, e.g. eggshells, mollusk shells
Abstract
The invention relates to the removal of paraxyleneThe field relates to a PX adsorbent, a preparation method thereof and a method for adsorbing paraxylene by using the PX adsorbent. The PX adsorbent is prepared by taking crab shells as raw materials and adopting a high-temperature oxygen-free hybridization technology, has a black carbon appearance, a pore diameter of 1-5nm and a pore volume of 1.023-1.149cm3Per gram, specific surface area of 1650.22-2045.68m2Analysis by X-ray diffraction spectrometer shows that the sample has two diffraction peaks at 20.3 deg. and 43.1 deg., and infrared spectrum at 3472cm‑1，2351cm‑1，1531cm‑1，1439cm‑1，1068cm‑1，862cm‑1There is an absorption peak. The PX adsorbent can efficiently remove PX remained in a water body, the PX removal rate in five minutes is up to 87.5%, and the highest adsorption quantity is 393.10 mg/g; the invention provides a new idea for the high-value utilization of crab shell waste resources, develops a new adsorbing material for the removal of PX, and has very important significance for solving the increasingly serious PX pollution problem in China.
Description
Technical Field
The invention relates to the field of removal of paraxylene, in particular to a PX adsorbent, a preparation method thereof and a method for adsorbing paraxylene by using the PX adsorbent.
Technical Field
PX (para xylene), which is common chemical products of aromatic hydrocarbon series, is mainly used for preparing terephthalic acid or polyester, and is a raw material for producing various industrial plastics. According to incomplete statistics, the total yield of PX in 2017 in China reaches 1380 ten thousand tons, and the capacity tends to increase year by year. In addition, 4000 million tons of Zhejiang petrochemical/year refining integrated first-term project has been put into operation in Zhoushan green petrochemical base in 5 months in 2019, wherein the annual output of PX is as high as 400 million tons. However, with the increase of the PX yield, the environmental problems brought with the PX production are increasingly prominent, leakage and other problems inevitably exist in the PX production, processing and transportation processes, and the PX exposed in the air and the water body can cause certain harm and even damage to the human health. Therefore, in recent years, removal of PX has been a focus of attention for researchers. Currently, the main methods for removing PX are chemical oxidation, catalytic degradation, adsorption, biological treatment, etc., wherein adsorption is the most economical and widely used method for removing PX. The existing adsorbent has poor adsorption effect on PX, so that a PX adsorbent with high adsorption capacity, high removal rate, reusability and stable structure is always a hot point of research.
Disclosure of Invention
The PX adsorbent is prepared by taking crab shells as raw materials and adopting a high-temperature oxygen-free hybridization technology, has a black carbon appearance, a pore diameter of 1-5nm and a pore volume of 1.023-1.149cm3Per gram, specific surface area of 1650.22-2045.68m2Analysis by X-ray diffraction spectrometer shows that the sample has two diffraction peaks at 20.3 deg. and 43.1 deg., and infrared spectrum at 3472cm-1，2351cm-1，1531cm-1，1439cm-1，1068cm-1，862cm-1Has an absorption peak.
The invention adopts a specific surface area and pore diameter analyzer to determine N of PX adsorbent2The adsorption isotherm and the related determination result show that the adsorption isotherm of the PX adsorbent is IV-type isotherm at P/P0>The presence of a hysteresis loop at 0.4 indicates the presence of mesopores.
Further, the invention adopts BET method to analyze its aperture and specific surface area, the size distribution of PX adsorbent is mainly in 1-5nm range, composed of micropore and mesopore, and is a porous grade biological carbon; the specific surface area of the PX adsorbent is up to 2045.68m2Per g, pore volume 1.149cm3(ii)/g; the PX adsorbent disclosed by the invention has the advantages of large specific surface area, high and uniform porosity and contribution to improving the PX adsorption capacity.
The invention utilizes an X-ray diffraction spectrometer to analyze the crystal structure and the phase structure of the PX adsorbent, wherein the PX adsorbent has two diffraction peaks of 20.3 degrees and 43.1 degrees, which shows that the PX adsorbent has the characteristics of chitin (21-2) plane and crystalline graphite (100) plane; the diffraction peak at 43.1 degrees 2 theta indicates that amorphous carbon exists in the PX adsorbent, so that the adsorption efficiency of PX can be enhanced.
The surface chemical functional groups are determined by Fourier transform infrared spectroscopy, and the infrared spectroscopy of the PX adsorbent shows that the surface chemical functional groups are about 3472cm-1，2351cm-1，1531cm-1，1439cm-1，1068cm-1，862cm-1Has an absorption peak. The infrared spectrum of the PX adsorbent shows that the PX adsorbent has a characteristic peak of chitin, which is consistent with an XRD (X-ray diffraction) pattern; in addition, the spectrum of oxygen-containing functional groups such as-OH, C ═ O and the like is also observed as potential adsorption sites, so that the adsorption performance of PX is more excellent.
According to the invention, the surface appearance of the PX adsorbent is observed by using a scanning electron microscope, and the effective arrangement of mesopore lamellar pores of the crab shell carbon is found, so that more pits and cracks exist; presenting a rich porous structure.
A preparation method of PX adsorbent comprises using crab shell as raw material, soaking in hydrochloric acid to remove calcium carbonate, pulverizing, performing high temperature anaerobic carbonization, grinding into powder for activation, repeatedly washing with distilled water to neutrality, and oven drying to obtain PX adsorbent.
Further, a preparation method of the PX adsorbent comprises the following steps:
1) crab shell pretreatment
Soaking crab shell in hydrochloric acid solution for 12 hr to remove calcium carbonate, washing with distilled water to remove residual hydrochloric acid and salt on the surface, and drying in oven at 60-80 deg.C for 24 hr;
2) charring crab shell
Crushing the crab shells pretreated in the step 1), putting the crushed crab shells into a tube furnace, and performing reaction in N2Carrying out high-temperature carbonization under the atmosphere protection;
3) crab shell activation
Grinding the crab shells carbonized in the step 2) into powder with the granularity of 100-200 meshes for subsequent activation experiments, naturally cooling the activated crab shell powder, repeatedly washing crab shell carbon with distilled water until the crab shell carbon is neutral, and drying in an oven at the temperature of 60-80 ℃ for 24 hours to obtain the PX adsorbent.
Preferably, the concentration of the hydrochloric acid in the step 1) is 2 mg/L.
Preferably, the weight-to-volume ratio (unit g/mL) of the crab shells to the hydrochloric acid in the step 1) is 1: 2.
Preferably, the carbonization condition in the step 2) is N2The flow rate of the tube furnace is 200mL/min, the temperature of the tube furnace is raised to 600-800 ℃ at the speed of 10 ℃/min, and then the temperature is maintained for 2-3 h.
Preferably, the activation conditions in step 3) are: mixing the carbonized crab shell powder with KOH solid according to the weight ratio of 1:1-2:1, placing the mixture in a tubular furnace for activation, and adding N2The flow rate of (2) is 200mL/min, the temperature is raised to 800 ℃ at a rate of 10 ℃/min, and then the temperature is maintained for 1-2 h.
A method of adsorbing PX with a PX adsorbent, comprising the steps of:
1) adding a PX adsorbent to a PX aqueous solution, wherein the weight-to-volume ratio (g/L) of the PX adsorbent to the PX aqueous solution is 1: 5;
2) adjusting the pH value of the mixed solution to 7 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, and adsorbing at 25 ℃;
3) and (3) centrifuging the mixed solution at 4000r/min for 5min, taking supernate, measuring the OD value of the supernate, and calculating the adsorption quantity of PX by the formula (1).
Preferably, the concentration of PX in the PX aqueous solution in said step 1) is 80 mg/L.
Preferably, the adsorption time in step 2) is 5-60 min.
The inventor is continuously dedicated to developing a high specific surface area biochar material, and early researches find that biochar has high specific surface area, is rich in various mineral elements and active groups, and can be used as an ideal PX adsorbent material; the invention adopts high-temperature anaerobic hybridization technology to prepare the waste crab shells into a novel charcoal adsorbent, which can efficiently remove PX remained in a water body, wherein the PX removal rate in five minutes is up to 87.5%, and the maximum adsorption amount is up to 393.10 mg/g; the invention provides a new idea for the high-value utilization of crab shell waste resources, develops a new adsorbing material for the removal of PX, and has very important significance for solving the increasingly serious PX pollution problem in China.
Drawings
Fig. 1 is a plot of the specific surface area and pore size of the PX adsorbent in example 1.
FIG. 2 is an XRD pattern of PX adsorbent in example 1 and crab shell feedstock in comparative example 1;
wherein, a is the XRD pattern of the crab shell raw material in the comparative example 1, and b is the XRD pattern of the PX adsorbent prepared in the example 1.
FIG. 3 FTIR plots of PX adsorbent in example 1 and crab shell feed in comparative example 1;
wherein, a is the FTIR spectrum of the crab shell raw material in the comparative example 1, and b is the FTIR spectrum of the PX adsorbent prepared in the example 1.
FIG. 4 is an SEM image of PX adsorbent in example 1 and crab shell feed in comparative example 1;
wherein a is an electron microscope image of crab shell raw material in comparative example 1 magnified 5000 times, b is an electron microscope image of crab shell raw material in comparative example 1 magnified 10000 times, c is an electron microscope image of PX adsorbent in example 1 magnified 5000 times, and d is an electron microscope image of PX adsorbent in example 1 magnified 10000 times.
Fig. 5 is a graph of the effect of different concentrations on the adsorption efficiency of PX adsorbent.
Fig. 6 is a graph of the effect of different times on the adsorption efficiency of PX adsorbents.
Fig. 7 is a graph of the effect of different pH on the adsorption efficiency of PX adsorbents.
Detailed Description
The following examples are intended to further illustrate the present invention, but they are not intended to limit or restrict the scope of the invention.
Crab shell sources are as follows: zhoushan city aquatic product market
A tube furnace: SGL-1700-III Zhengzhou honglang instruments and Equipment Limited
Oven: HH.S11-6 Tianjin Tesla Co Ltd
The solvent used in the present invention is not particularly limited, and a commercially available conventional solvent can be used, for example, hydrochloric acid is analytically pure and is available from Shanghai pharmaceutical chemistry Co.
The X-ray powder diffraction instrument and the test condition related by the invention are that the change of the X-ray diffraction intensity of a sample along with 2 theta is measured by adopting a D/max 2500X-ray diffractometer of Shimadzu Japan so as to obtain the crystallinity of the sample.
The infrared spectrometer and the test conditions adopted by the invention are that the American Nicolet Nexus 6700FTIR Fourier transform infrared spectrometer is used for detecting and analyzing the chemical structure and the functional group of the sample. In the scanning range of 500cm-1-4000cm-1Under the condition (2), the obtained infrared spectrogram can be used as a basis for judging the composition of the sample.
The electron microscope and the test conditions adopted by the invention are that a sample is analyzed by using Japan Quanta 200F, 10mg of the sample is uniformly covered on a test board, and then the appearance and the specific structure of the sample are observed by using a scanning electron microscope under different multiples.
The specific surface area and pore size analysis tester adopted by the invention has the test conditions that 30-40mg of sample is weighed by using BK122T-B type specific surface area and porosity analyzer, the system is heated to 300 ℃, the Q value is measured after the liquid nitrogen rises until the two results are less than 0.001h, and the liquid nitrogen is added and the test conditions are as follows by using a multipoint BET method: the specific surface area of the biochar was measured at a liquid nitrogen temperature (77k), and the pore size distribution was measured by the DFT method.
The invention relates to the calculation of the adsorption rate of PX adsorbent to PX adsorption:
wherein q ist(mg/g) is the amount of PX adsorbed by the adsorbent, C0(mg/L) and Ct(mg/L) is the initial concentration and the concentration at a certain reaction time point, V is the volume of the solution (L), and m (g) is the weight of the adsorbent.
Comparative example 1 preparation of crab Shell starting Material
Soaking 40g of swimming crab shells in 80mL of hydrochloric acid solution with the concentration of 2mg/L for 12 hours to remove calcium carbonate, washing with distilled water to remove residual hydrochloric acid and salts on the surfaces, and then drying in an oven at 70 ℃ for 24 hours; then crushed into powder with the granularity of 200 meshes.
Example 1 preparation of PX adsorbent
1) Crab shell pretreatment
Soaking 40g of swimming crab shells in 80mL of hydrochloric acid solution with the concentration of 2mg/L for 12 hours to remove calcium carbonate, washing with distilled water to remove residual hydrochloric acid and salts on the surfaces, and then drying in an oven at 70 ℃ for 24 hours;
2) charring crab shell
Crushing the swimming crab shells pretreated in the step 1), placing the crushed swimming crab shells in a tube furnace, and performing reaction in a reactor N2High temperature carbonization under the protection of atmosphere, N2The flow rate of (2) is 200mL/min, the temperature of the tube furnace is raised to 700 ℃ at the speed of 10 ℃/min, and then the temperature is maintained for 2 h;
3) crab shell activation
Grinding the portunus trituberculatus shells carbonized in the step 2) into powder with the granularity of 200 meshes for subsequent activation experiments; mixing the carbonized crab shell powder with KOH solid according to the weight ratio of 2:1, placing the mixture in a tubular furnace for activation, and adding N2The flow rate of the PX adsorbent is 200mL/min, the temperature is increased to 800 ℃ at the speed of 10 ℃/min, then the temperature is maintained for 2h, the PX adsorbent is naturally cooled, repeatedly washed by distilled water until the temperature is neutral, and then dried in an oven at the temperature of 80 ℃ for 24h to obtain 4.2g of the PX adsorbent.
The PX adsorbent is carbon black in appearance, and the specific surface area of the PX adsorbent is determined to be 2045.68m2G, pore diameter of 1-5nm and pore volume of 1.149cm3The specific surface area and the pore diameter diagram are shown in figure 1; the X-ray diffraction spectrometer analyzes that the X-ray diffraction spectrometer has two diffraction peaks of 20.3 degrees and 43.1 degrees, and an XRD pattern is shown in figure 2; the infrared spectrum showed that it was 3472cm-1，2351cm-1，1531cm-1，1439cm-1，1068cm-1，862cm-1Has an absorption peak, and an infrared spectrogram is shown in figure 3;
10mg of the PX adsorbent in example 1 and the crab shell raw material in comparative example 1 were uniformly covered on a test board, and then the morphology and specific structure of the PX adsorbent and the crab shell raw material were observed under different multiples by a scanning electron microscope, and the results are shown in FIG. 4.
Example 2 preparation of PX adsorbent
1) Crab shell pretreatment
Soaking 30 g of crab shell of hairy crab in 60mL of hydrochloric acid solution with the concentration of 2mg/L for 12 hours to remove calcium carbonate, washing with distilled water to remove residual hydrochloric acid and salt on the surface, and then drying in an oven at 60 ℃ for 24 hours;
2) charring crab shell
Crushing the pretreated crab shells of the hairy crabs in the step 1), putting the crushed crab shells into a tube furnace, and putting the crushed crab shells into a furnace N2High temperature carbonization under the protection of atmosphere, N2The flow rate of (2) is 200mL/min, the temperature of the tube furnace is raised to 600 ℃ at the speed of 10 ℃/min, and then the temperature is maintained for 2 h;
3) crab shell activation
Grinding the crab shells of the hairy crabs carbonized in the step 2) into powder with the granularity of 100 meshes for subsequent activation experiments; mixing the carbonized crab shell powder with KOH solid according to the weight ratio of 1:1, placing the mixture in a tubular furnace for activation, and adding N2The flow rate of the PX adsorbent is 200mL/min, the temperature is increased to 800 ℃ at the speed of 10 ℃/min, then the temperature is maintained for 1h, the PX adsorbent is naturally cooled, repeatedly washed by distilled water until the temperature is neutral, and then dried in an oven at the temperature of 60 ℃ for 24h to obtain 3g of the PX adsorbent.
The PX adsorbent is carbon black, and the specific surface area is determined to be 1650.22m2Per g, pore diameter of 2-5nm, pore volume of 1.023cm3Analysis by X-ray diffraction spectrometer shows that the sample has two diffraction peaks at 20.3 deg. and 43.1 deg., and infrared spectrum at 3472cm-1，2351cm-1，1531cm-1，1439cm-1，1068cm-1，862cm-1There is an absorption peak.
Example 3 preparation of PX adsorbent
1) Crab shell pretreatment
50g of blue crab shell is soaked in 100mL of hydrochloric acid solution with the concentration of 2mg/L for 12 hours to remove calcium carbonate, and then is washed by distilled water to remove residual hydrochloric acid and salts on the surface, and then is dried in an oven at 80 ℃ for 24 hours.
2) Charring crab shell
Crushing the blue crab shells pretreated in the step 1), placing the crushed blue crab shells in a tube furnace, and performing reaction in a reactor N2High temperature carbonization under the protection of atmosphere, N2The flow rate of (2) was 200mL/min, and the tube furnace temperature was raised to 800 ℃ at a rate of 10 ℃/min and then maintained at that temperature for 2 hours.
3) Crab shell activation
Will be described in detail2) The crab shell of the middle-carbonized blue crab is ground into powder with the granularity of 200 meshes and is used for the subsequent activation experiment. Mixing the carbonized crab shell powder with KOH solid according to the weight ratio of 1:1, placing the mixture in a tubular furnace for activation, and adding N2The flow rate of the PX adsorbent is 200mL/min, the temperature is increased to 800 ℃ at the speed of 10 ℃/min, then the temperature is maintained for 2 hours, the PX adsorbent is naturally cooled, repeatedly washed by distilled water until the temperature is neutral, and then dried in an oven at the temperature of 60 ℃ for 24 hours, so that 5.2 g of the PX adsorbent is obtained.
The PX adsorbent is carbon black, and the specific surface area is determined to be 1865.05m2G, pore diameter of 1-5nm and pore volume of 1.092cm3Analysis by X-ray diffraction spectrometer of the sample shows two diffraction peaks at 20.3 deg. and 43.1 deg. and its infrared spectrum shows that it is 3472cm-1，2351cm-1，1531cm-1，1439cm-1，1068cm-1，862cm-1There is an absorption peak.
Example 4 adsorption of PX by PX adsorbent (different concentrations)
1) 0.01g of the PX adsorbent prepared in example 1 was mixed with 50mL of PX aqueous solution with the concentration of 10, 20, 40, 60, 80, and 100mg/L, respectively, and adsorption was performed at 25 deg.C, and the influence of PX with different initial concentrations on adsorption efficiency was analyzed.
2) The pH of the mixed solution was adjusted to 7 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, and the adsorption time was 60 min.
3) The mixed solution was centrifuged at 4000r/min for 5min, the OD value of the supernatant was measured, and the adsorption amount of PX was calculated by the formula (1), and the results are shown in table 1 and fig. 5.
As can be seen from table 1: the adsorption amount of PX increases with the increase of the concentration of the PX aqueous solution, and at 80mg/L, the adsorption amount of PX reaches the maximum, and then decreases with the increase of the concentration of the PX aqueous solution.
TABLE 1 influence of adsorption concentration on the adsorption efficiency of PX
| PX aqueous solution concentration (mg/L) | Amount of PX adsorbed (mg/g) |
| 10 | 44.00 |
| 20 | 107.45 |
| 40 | 211.52 |
| 60 | 295.40 |
| 80 | 393.10 |
| 100 | 380.21 |
Example 5 adsorption of PX by PX adsorbent (different times)
1) 0.01g of PX adsorbent in example 1 is taken and respectively mixed with 50mL of PX aqueous solution with the concentration of 80 mg/L;
2) adjusting the pH value of the mixed solution to 7 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, and analyzing the influence of different adsorption times on the adsorption efficiency at 25 ℃ for adsorption time from 5min to 120 min;
3) the mixed solution was centrifuged at 4000r/min for 5min, the OD value of the supernatant was measured, and the adsorption amount of PX was calculated by the formula (1), and the results are shown in table 2 and fig. 6.
As can be seen from table 2, the adsorption amount of PX increases with the increase of the adsorption time, the adsorption rate can reach 87.5% at 5min, and the adsorption amount of PX reaches the maximum at 60min, and the adsorption rate can reach 98.3%, and then decreases with the increase of the adsorption time.
TABLE 2 Effect of different time on the adsorption efficiency of PX
| Adsorption time (min) | Amount of PX adsorbed (mg/g) |
| 0 | 0 |
| 5 | 350.00 |
| 30 | 378.20 |
| 60 | 393.10 |
| 90 | 389.15 |
| 120 | 380.20 |
Example 6 adsorption of PX by PX adsorbent (different PH)
1) 0.01g of PX adsorbent in example 1 is mixed with 50mL of PX aqueous solution with the concentration of 80 mg/L;
2) the pH of the mixed solution was adjusted to 5, 6, 7, 8 and 9 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, respectively, and the mixture was adsorbed at 25 ℃ for 60 min.
3) Centrifuging the mixed solution at 4000r/min for 5min, collecting supernatant, measuring OD value, and calculating PX absorption by formula (1)The results are shown in Table 3 and the figure7As shown.
As can be seen from Table 3, the adsorption amount of PX was the largest at a pH value of 7.
TABLE 3 Effect of different pH on the adsorption efficiency of PX
| Different pH value | Amount of PX adsorbed (mg/g) |
| 5 | 382.50 |
| 6 | 375.80 |
| 7 | 393.10 |
| 8 | 390.50 |
| 9 | 368.10 |
Example 7 adsorption of PX by PX adsorbent
1) 0.01g of PX adsorbent in example 1 is mixed with 50mL of PX aqueous solution with the concentration of 80 mg/L;
2) the pH of the mixed solution was adjusted to 7 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, and the mixture was adsorbed at 25 ℃ for 60 min.
3) The mixed solution was centrifuged at 4000r/min for 5min, the supernatant was taken and measured for its OD value, and the adsorbed amount of PX was calculated by the formula (1) to be 393.10 mg/g.
Example 8 the inventors searched for PX adsorbents in the prior art and listed the corresponding adsorption effects, and the results are shown in table 4.
TABLE 4
Wherein Chin et al, 2007 refers to Chin, C.M., Shih, L., Tsai, H., Liu, T.2007.Adsorption of o-xylene and p-xylene from water by SWCNTs, Carbon,45(6),1254 + 1260;
carvalho et al, 2012 refers to Carvalho, M., Da Motta, M., Benachour, M., salts, D., Abreu, C.2012.evaluation of BTEX and phenol removal from aqueous solution by Multi-solution adsorption on to particulate inorganic Mater 239, 95-101;
anjum et al, 2019 refers to Anjum, H., Johanari, K., Gnanasundaram, N., Apmushy, A., Thanabalan, M.2019.impact of surface modification on adaptive removal, BTX on to activated carbon.J. Mol Liq,280, 238-;
moura et al, 2011 refers to Moura, C.P., Vidal, C.B., Barros, A.L., Costa, L.S., Vasconcellos, L.C., Dias, F.S., Nasciento, R.F.2011.Adorption of BTX (benzene, toluene, o-xylene, and p-xylene) from aqueous solutions by modified periodic tissue Interface Sci,363(2),626 cake 634;
yu et al, 2012 refers to Yu, F, Wu, Y, Ma, J.2012. injection of the pore structure and surface chemistry on adsorption of ethylene and xylene isometers by KOH-activated multi-wall carbon n nanoparticles Mater,237, 102-;
mangin et al, 2001 refers to mangin, c.l., Yue, z., Economy, j., Maloney, s., kemmes, p., Cropek, d.2001.adsorption of organic contaminants from using particulate acids chem.mater, 13(7), 2356-;
kim et al, 2013 refers to Kim, s., Park, j., Lee, c.2013.
Surface-functionalized mesoporous silica nanoparticles as sorbents for BTEX.J.Porous Mater,20(5),1087-1093。
Claims (4)
1.A PX adsorbent, characterized by: the PX adsorbent is prepared from crab shells as a raw material by adopting a high-temperature oxygen-free hybridization technology, and has a black carbon appearance, a pore diameter of 1-5nm and a pore volume of 1.023-1.149cm3Per gram, specific surface area of 1650.22-2045.68m2Analysis by X-ray diffraction spectrometer of the powder with two diffraction peaks of 20.3 and 43.1 shows that the infrared spectrum is 3472cm-1，2351 cm-1，1531 cm-1，1439 cm-1，1068 cm-1， 862 cm-1Has an absorption peak; the PX adsorbent is prepared by taking crab shells as a raw material, soaking in hydrochloric acid, removing calcium carbonate, crushing, performing high-temperature anaerobic carbonization, further grinding into powder after carbonization, activating, repeatedly washing with distilled water to neutrality, and drying; the method specifically comprises the following steps:
1) crab shell pretreatment
Soaking crab shell in hydrochloric acid solution for 12 hr to remove calcium carbonate, washing with distilled water to remove residual hydrochloric acid and salt on the surface, and drying in oven at 60-80 deg.C for 24 hr;
2) charring crab shell
Crushing the crab shells pretreated in the step 1), placing the crushed crab shells in a tube furnace, and performing reaction in a reactor N2Carrying out high-temperature carbonization under the atmosphere protection;
3) crab shell activation
Grinding the crab shells carbonized in the step 2) into powder with the granularity of 100-200 meshes for subsequent activation experiments, naturally cooling the activated crab shell powder, repeatedly washing crab shell carbon with distilled water until the crab shell carbon is neutral, and drying the crab shell carbon in an oven at the temperature of 60-80 ℃ for 24 hours to obtain a PX adsorbent;
wherein the concentration of the hydrochloric acid in the step 1) is 2mg/L, and the weight-volume ratio g/ml of the crab shells to the hydrochloric acid in the step 1) is 1: 2;
the carbonization condition in the step 2) is N2The flow rate of the tube furnace is 200mL/min, the temperature of the tube furnace is raised to 600-800 ℃ at the speed of 10 ℃/min, and then the temperature is maintained for 2-3 h;
in the step 3)The activation conditions are as follows: mixing the carbonized crab shell powder with KOH solid according to the weight ratio of 1:1-2:1, placing the mixture in a tubular furnace for activation, and adding N2The flow rate of (2) is 200mL/min, the temperature is raised to 800 ℃ at a rate of 10 ℃/min, and then the temperature is maintained for 1-2 h.
2. A method of adsorbing PX with the PX adsorbent of claim 1, comprising the steps of:
1) adding a PX adsorbent into a PX aqueous solution, wherein the weight-volume ratio of the PX adsorbent to the PX aqueous solution is 1 g: 5L;
2) adjusting the pH value of the mixed solution to 7 by adding 0.1mol/L hydrochloric acid or 0.1mol/L sodium hydroxide, and adsorbing at 25 ℃;
3) and (3) centrifuging the mixed solution at 4000r/min for 5min, taking supernate, measuring the OD value of the supernate, and calculating the adsorption quantity of PX by the formula (1).
3. The method of claim 2 where a PX adsorbent adsorbs PX with a concentration of 80mg/L in the PX aqueous solution in step 1).
4. The method of claim 2 for adsorbing PX with a PX adsorbent, wherein said adsorbing time in step 2) is 5-60 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911174660.0A CN110961087B (en) | 2019-11-26 | 2019-11-26 | PX adsorbent and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911174660.0A CN110961087B (en) | 2019-11-26 | 2019-11-26 | PX adsorbent and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110961087A CN110961087A (en) | 2020-04-07 |
| CN110961087B true CN110961087B (en) | 2022-06-21 |
Family
ID=70031737
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911174660.0A Active CN110961087B (en) | 2019-11-26 | 2019-11-26 | PX adsorbent and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110961087B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112691642B (en) * | 2020-12-15 | 2022-08-02 | 浙江海洋大学 | Diesel oil adsorbent and preparation method thereof |
| CN113181874A (en) * | 2021-03-15 | 2021-07-30 | 浙江海洋大学 | Hierarchical porous mussel shell biological adsorbent and preparation thereof |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7053256B2 (en) * | 2001-09-04 | 2006-05-30 | The Regents Of The University Of Michigan | Selective sorbents for purification of hydrocarbons |
| CN101497022B (en) * | 2008-01-31 | 2011-06-15 | 中国石油化工股份有限公司 | Coalescence type zeolite sorbent and preparation method thereof |
| CN103566888B (en) * | 2012-08-02 | 2015-03-25 | 中国石油化工股份有限公司 | Activation method for p-xylene adsorbent carrier and preparation method of p-xylene adsorbent |
| CN102951698A (en) * | 2012-12-18 | 2013-03-06 | 福州大学 | Method for treating PX (para-xylene) wastewater by using active carbon as adsorbent |
| CN108568283B (en) * | 2017-07-12 | 2021-03-26 | 舟山赛莱特海洋科技有限公司 | Adsorbent prepared from kelp as main material |
| CN107570115A (en) * | 2017-09-28 | 2018-01-12 | 浙江海洋大学 | A kind of preparation method of crab shell charcoal |
| CN109046241A (en) * | 2018-08-15 | 2018-12-21 | 浙江海洋大学 | A kind of preparation method based on crab shell biomass carbon oil stain absorbent |
| CN109225138B (en) * | 2018-10-31 | 2021-06-22 | 福州大学 | Modified activated carbon for efficiently adsorbing AOCs in PTA wastewater and preparation method thereof |
-
2019
- 2019-11-26 CN CN201911174660.0A patent/CN110961087B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110961087A (en) | 2020-04-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Lv et al. | A functional activated carbon for efficient adsorption of phenol derived from pyrolysis of rice husk, KOH-activation and EDTA-4Na-modification | |
| Hou et al. | Hydrothermal conversion of bamboo shoot shell to biochar: Preliminary studies of adsorption equilibrium and kinetics for rhodamine B removal | |
| Ahmed et al. | High-performance porous biochar from the pyrolysis of natural and renewable seaweed (Gelidiella acerosa) and its application for the adsorption of methylene blue | |
| Zhu et al. | An environmentally friendly carbon aerogels derived from waste pomelo peels for the removal of organic pollutants/oils | |
| Yao et al. | Magnetic activated biochar nanocomposites derived from wakame and its application in methylene blue adsorption | |
| Mu et al. | NaOH-modified mesoporous biochar derived from tea residue for methylene Blue and Orange II removal | |
| Wang et al. | Removal of organic solvents/oils using carbon aerogels derived from waste durian shell | |
| Foo et al. | Microwave assisted preparation of activated carbon from pomelo skin for the removal of anionic and cationic dyes | |
| CN110961087B (en) | PX adsorbent and preparation method thereof | |
| Guan et al. | Amphiphilic hollow carbonaceous microspheres for the sorption of phenol from water | |
| CN111606405A (en) | Method for degrading organic pollutants in water by activating peracetic acid through nitrogen-doped carbon material | |
| Xu et al. | Improving abiotic reducing ability of hydrothermal biochar by low temperature oxidation under air | |
| CN110548487B (en) | Hydrothermal carbon-based composite material, and preparation and application thereof | |
| Anbia et al. | Synthesis of polyelectrolyte-modified ordered nanoporous carbon for removal of aromatic organic acids from purified terephthalic acid wastewater | |
| Jin et al. | Combining biological and chemical methods to disassemble of cellulose from corn straw for the preparation of porous carbons with enhanced adsorption performance | |
| Hou et al. | MIL-101 (Cr)/graphene hybrid aerogel used as a highly effective adsorbent for wastewater purification | |
| Zhang et al. | A new type of calcium-rich biochars derived from spent mushroom substrates and their efficient adsorption properties for cationic dyes | |
| Ateş et al. | Evaluation of characteristics of raw tea waste-derived adsorbents for removal of metals from aqueous medium | |
| Ghamsari et al. | Highly fast and efficient removal of some cationic dyes from aqueous solutions using sulfonated-oxidized activated carbon | |
| Doke et al. | Kinetics and equilibrium isotherm for adsorption of basic blue 9 dye onto activated charcoal prepared from Bhagar seed husk | |
| Yang et al. | Kinetics and equilibrium study for the adsorption of lysine on activated carbon derived from coconut shell | |
| Liu et al. | A comparison of the influence of flocculent and granular structure of sludge on activated carbon: preparation, characterization and application | |
| CN112691642B (en) | Diesel oil adsorbent and preparation method thereof | |
| CN109319777A (en) | A kind of pinecone base prepares the method and its application of biological activated carbon | |
| Gao et al. | Adsorption of basic Magenta on graphene oxide-modified sugarcane bagasse |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |