72 results about "Cadmium adsorption" patented technology

The invention provides a modified biochar preparation method, and belongs to the technical field of chemical processes. The method comprises the following steps: a biomass material used as a raw material is dried, calcined and ground to obtain biochar, a ferric salt and a ferrous salt are mixed according to a molar ratio of 2:1, the salt mixture is mixed with ammonia water to prepare a ferroferric oxide colloid precipitate, the biochar is added to the ferroferric oxide colloid precipitate, the obtained mixture is stirred under a nitrogen introduction condition, and then stands in a closed manner to obtain magnetic biochar, and finally the magnetic biochar and a certain proportion of a nitrogen-containing precursor are placed in a tubular furnace and are calcined to obtain modified biochar. The modified biochar provided by the invention uses the biomass material as the raw material, and has the advantages of maintaining of efficient metal cadmium adsorption capability, convenience in separation and recovery, improvement of the recovery rate of the biomass material, and improvement of the efficiency of removal of metal cadmium pollution in water of an adsorption process.

The invention relates to a high-cadmium-adsorption filamentous fungus Paecilomyces lilacinus XLA, and a preparation method and an application thereof. The preparation method comprises the following steps: 1, weighing a pot experiment soil sample used for heavy metal restoration and having a content of heavy metal cadmium of 50mg/Kg, adding to sterile water with glass beads, oscillating on a constant temperature shaking table, allowing an obtained solution to stand, taking an obtained supernatant, and carrying out serial dilution; 2, coating a Martin flat containing 60mM of cadmium with different dilution rates of dilutions, allowing the obtained flat to stand for a moment, inverting on a constant temperature culturing box, and culturing; 3, carrying out streaking purification of single colonies growing on the flat, coating the Martin flat with the obtained single colonies, and culturing; 4, carrying out separating screening to obtain the Paecilomyces lilacinus XLA stably resisting cadmium, and preserving on a PDA inclined plane for later use. The Paecilomyces lilacinus XLA is preserved and has a preservation number of CCTCC NO:M2012135. Viable and non-viable organism of the XLA can efficiently adsorb and remove the heavy metal cadmium in heavy metal sewage, so the XLA has the advantages of low cost and simple technology, and has an efficient restoration potential of heavy metal polluted soil and water.

The invention discloses a screening method for heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii. The screening method comprises: selecting a suitable screening concentration for heavy metal cadmium adsorption mutants according to the influence of different cadmium chloride concentrations on the growth of Chlamydomonas reinhardtii; Transformation to obtain Chlamydomonas reinhardtii mutants; screening out heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii, the screening of heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii includes screening heavy metal cadmium sensitive mutants and screening heavy metal cadmium resistant mutants; identification screening Mutant genes of heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii. The invention achieves the technical effect of being able to obtain a large amount of Chlamydomonas heavy metal cadmium adsorption mutants simply and efficiently.

The invention discloses a method for planting suaeda salsa at a medium-low-cadmium saline-alkaline land and for extracting plant salt. The method comprises the steps of saline-alkaline land selection, saline-alkaline land improvement, soil cadmium adsorption treatment, and plant salt extraction. According to the soil cadmium adsorption treatment step, amaranthus retroflexus and elymus dahuricus are inter-planted and used for adsorbing cadmium in soil, wherein a preferable inter-planting ratio of amaranthus retroflexus and elymus dahuricus is 4:1, and a planting density is preferably 10*40cm. In the plant salt provided by the invention, cadmium content is reduced to 0.002mg/kg, sodium chloride content is 39%, potassium chloride content is 12%, Mg content is 4%, Ca content is 8%, and Fe content is 750mg/kg. With the method, a problem of excessively high cadmium content in plant salt extracted from suaeda salsa planted in the medium-low-cadmium saline-alkaline land is effectively solved.

A heavy metal cadmium deactivator for activating the activity of sulfur-reducing bacteria in rice field soil, and an application thereof. The deactivator is constituted by electron shuttles alone or electron shuttles and electron donors, but cannot be constituted by electron donors alone. The mass ratio of the electron donors to the electron shuttles is (1:3)-(1:8). Also, a heavy metal cadmium deactivating method for activating the activity of microorganisms in rice field soil, such as sulfur-reducing bacteria. By applying the functional deactivator to rice field soil, the activity of microorganisms, such as sulfur-reducing bacteria, can be activated, thereby accelerating the reduction process of sulfur and iron in soil to facilitate the fixation of cadmium; cadmium adsorption and accumulation in rice is reduced to achieve secure production in fields moderately or lightly polluted by cadmium.

A method for removing cadmium ions from wastewater by adsorption-precipitation with waste beer yeast comprises the steps of preparing waste beer yeast adsorbent from waste beer yeast, adding into cadmium-containing wastewater solution, adjusting pH in the range of 5-8, stirring at room temperature and stirring speed of 800-1,000 r/min, standing for 120-210 min, and removing the waste beer yeast adsorbent with adsorbed cadmium ions. The inventive method removes cadmium ions from cadmium-containing wastewater by utilizing good cadmium adsorption and good precipitation effect of waste beer yeast; has the advantages of simple process, high treatment efficiency, low cost, and no secondary pollution; and is very important for controlling cadmium-containing wastewater pollution.

The invention discloses filamentous fungi Epicoccum nigrum FXZ2 which is collected at a China General Microbiological Culture Collection Center. The collection number of the Epicoccum nigrum FXZ2 is CGMCC NO. 13573. The strain is applied to biological remediation of heavy metal lead and cadmium pollution. Experiments prove that the Epicoccum nigrum FXZ2 has high tolerance and adsorptivity for lead and cadmium, the cadmium adsorption capacity of phage of the strain is higher than that of active bacteria, the lead adsorption capacity of the active bacteria is higher than that of the phage, and the strain can remarkably promote plant growth under stress of heavy metal pollution, has good accumulation capacity for cadmium and is suitable for in-situ remediation of large-area heavy metal cadmium polluted soil.

The invention discloses an Enterobacter sp. FM-1 obtained through separation from mining soil, purifying and domestication, deposited at China Typical Culture Collection on December22, 2017, the deposit number of which is CCTCC M2017825. The method comprises such steps as taking soil, culturing soil, obtaining initial extracting solution, enriching culture with LB liquid medium, purifying culturewith LB solid medium, inoculating single colony into LB plate medium containing cadmium for further domestication and culture, and obtaining Enterobacter sp. FM-1 with high tolerance to cadmium. The Enterobacter sp. FM-1 has good tolerance and adsorption properties to cadmium. The adsorption of cadmium in the medium containing 4 mmol L-1 cadmium. The maximum adsorption rate of cadmium was 80.36% at 30 DEG C and pH 7. 190.45 mg g-1 of cadmium adsorption capacity was added under sterile operation at this time. The strain can be applied to the remediation of cadmium polluted water and soil with phytoremediation, and has a wide application prospect.

The invention provides an adsorption plate used for soil heavy metal cadmium adsorption and a preparation method thereof; rice straw and / or rice husk are/ is modified by phosphoric acid, and then mixed with sodium alginate to prepare a homogenate, the homogenate is added into a hollow cylindrical mold with an inner cavity, the cylindrical mold comprises a bottom surface and a side face tube which is in sealed connection with the edge of the bottom surface, a plurality of mutually parallel pillars are uniformly arranged on the bottom inner surface of the inner cavity of the mold in the direction of being perpendicular to the base plane of the mold, and the mold filled with the homogenate is frozen for shaping at the temperature of-20 DEG C, and then is demoulded to prepare a sodium alginate-rice straw and rice husk particle porous adsorption plate. The invention also provides application of the porous adsorption plate prepared by the method in adsorption and fixing of heavy metal cadmium in soil. The method has the advantages of simple operation and low cost, does not cause secondary pollution, and can be widely applied to repair of heavy metal cadmium polluted soil.

The invention discloses a method of reducing cadmium ions by M13 phage-mediated nano-iron and belongs to the field of environmental pollution governance and nano material preparation. According to the method, iron-adsorbed special M13 phage is adopted to synthesize uniformly dispersed zero-valent nano-iron particles in a mediated manner, and adopts cadmium-adsorbed special M13 phage M13 (Cd-s) to uniformly disperse divalent cadmium ions; then, the zero-valent nano-iron mediated and dispersed by the M13 phage is taken as a reducing agent so as to efficiently reduce divalent cadmium ions uniformly dispersed on the surface of M13(Cd-s). The method disclosed by the invention is high in reducing efficiency, quick in reaction, capable of efficiently catalyzing the divalent ions to be reduced into zero-valent cadmium on the phage surface, so that cadnimum pollution in environment is removed, and nano-particles of zero-valent iron, iron oxide and zero-valent cadmium also can be quickly prepared.

The invention discloses a biochar and its preparation method and application. The biochar is prepared by using Wedelia chinensis as a raw material. The preparation method is as follows: cleaning, drying and pulverizing the wedelia chinensis; placing the wedelia chinensis powder in nitrogen gas, The temperature for activation of Wedelia powder is 400-700°C, and the activation time is 0.5-10 hours; cooling to obtain the primary product of biochar; crushing the primary product of biochar to obtain biochar; the operation method of biochar to reduce cadmium in wastewater is: wastewater The concentration of cadmium in the medium is 10-550mg/L, the pH value of the wastewater is 2-8, the dosage of biochar is 0.5-1.5mg/mL, the adsorption time is 5min-24h, the temperature is 25°C, and the oscillation rate is 250rpm. The biological charcoal of the present invention is prepared by using the Wedelia chinensis as a raw material, which can not only absorb heavy metals in wastewater, but also eliminate the invasion hazard caused by the Wedelia chinensis; meanwhile, the wedelia chinensis biochar has a strong ability to adsorb cadmium.

The invention provides preparation of a potassium permanganate modified heavy metal cadmium adsorbent, wherein marine pollutant enteromorpha is used as a raw material; the raw material source is rich,the cost is low, the marine pollutant enteromorpha can be turned into wealth, and the potassium permanganate modified heavy metal cadmium adsorbent has important significance in marine pollution treatment and removal of heavy metals in water; meanwhile, the potassium permanganate modified enteromorpha charcoal adsorbent has the advantages of large specific surface area and high adsorption efficiency, the heavy metal cadmium adsorption efficiency of the potassium permanganate modified enteromorpha charcoal adsorbent is improved by 20 times or above compared with that of non-modified enteromorpha charcoal; therefore, the invention provides a new adsorbent material is provided for adsorbing heavy metal cadmium.

The invention provides a penicillium oxalicum strain capable of degrading cellulose and adsorbing cadmium. The penicillium oxalicum strain is classified and named as Penicilliumoxalicum WAF6, and thepreservation number of the penicillium oxalicum strain is ACCC 32731. The cadmium ion concentration tolerance range of the penicillium oxalicum strain is 0-150 mg/L; the penicillium oxalicum strain can produce cellulase, has a good degradation effect on rice straw, and is basically degraded on the 15th day when applied to degradation of the rice straw; meanwhile, the strain has the capacity to absorb heavy metal cadmium, and the penicillium oxalicum strain has a cadmium adsorption rate greater than 76% on the 30th day when applied to the treatment of cadmium-contaminated soil. The strain is applied to the bioremediation of a cadmium-contaminated rice field, and can achieve an effect of restoring the soil metal cadmium contamination while degrading the rice straw.

The invention discloses protease and a method for preparing low-cadmium rice polypeptide from the protease, and belongs to the technical field of bio-enzymes. The neutral protease suitable for industrial production provided by the invention has the advantages that the enzyme activity can be up to 5898.5 U/mL, the cadmium ion adsorption capability is realized, the enzymatic hydrolysis reaction conditions are mild, the reaction period is short, and one-step hydrolysis and adsorption can be realized. The content of rice protein peptide prepared from the protease is up to 97.2 percent, the cadmiumcontent is only 0.078 mg/kg, and the cadmium adsorption rate is 90 percent or above. By adopting the method, the industrial production cost can be lowered effectively, and green production of safe foods is realized.

The invention provides a purpureo cilliumsp with high resistance on cadmium, and an extracting method and application thereof. The bacterial strain belongs to purpureo cilliumsp, and is registered andpreserved in CGMCC (China General Microbiological Culture Collection Center) on September 12th, 2017; the preservation number is CGMCC No.14159; the ITS sequence is shown as SEQ.ID.NO:1. The bacterial strain has a cadmium adsorption function; the cadmium in soil can be adsorbed; the absorption of plants on the cadmium is reduced, so that the plant growth is promoted.

The invention discloses a cadmium removing adsorbent for marine products and a preparation method of the cadmium removing adsorbent. The cadmium removing adsorbent for the marine products is preparedfrom the following raw materials in part by weight: 20-30 parts of modified silica powder, 50-70 parts of fish bone meal, 25-50 parts of modified shell powder, 15-30 parts of shrimp shell powder, 10-30 parts of a complexing agent, 3-5 parts of sodium carbonate and 200-400 parts of a solvent. The invention further provides the preparation method of the cadmium removing adsorbent for the marine products. The method comprises the following steps: mixing the raw materials, drying the raw materials at 70-90 DEG C and grinding the raw materials into 30-50 meshes after drying. When the prepared cadmium removing adsorbent for the marine products is used for removing cadmium from the marine products, the marine products are not needed to be ground, and the cadmium removing rate is high; besides, daily domestic wastes such as shells, fish bones, shrimp shells and the like are recycled and turned into valuables, which is good for environmental protection and reduces the cost; meanwhile, the adsorbent has a certain removal effect on arsenic while effectively adsorbing cadmium.

The invention discloses a preparation method and application of an adsorbent for adsorbing heavy metal ions. A dispersion of two-dimensional nanosheets is obtained through alkali metal ion intercalation, liquid phase stripping and centrifugal screening of a layered clay material used as a raw material, and is used for efficiently adsorbing the heavy metal ions in sewage. The stripped two-dimensional nanosheets are large in acting area and high in adsorption capacity and are dispersed into water to prepare the adsorbent. The adsorbent has the advantages of large adsorption capacity, good stability, wide adaptive temperature range and the like, and can effectively remove common heavy metal ions (nickel, cobalt and cadmium) in sewage. The preparation method of the adsorbent has the advantagesof environmental friendliness, safety, easiness in operation and the like. In addition, the clay material is low in price in nature and easy to obtain, and the preparation cost can be effectively reduced.

The invention relates to a plant material adsorbent for reducing the cadmium content of tobacco extracting liquid. The plant material adsorbent is prepared by adopting the steps: crushing root systems of pokeberry serving as raw materials; soaking the crushed materials into diluted acid and performing modification treatment; and filtering and then washing with deionized water to finally obtain the plant material adsorbent. The tobacco extracting liquid with the reduced cadmium content is obtained by adding the plant material adsorbent into the tobacco extracting liquid, adsorbing, and filtering and removing the plant material adsorbent. The plant material adsorbent has the advantages that the root systems of the modified cadmium hyperaccumulator plants, namely, pokeberry are used as the adsorbent, the cadmium content in the root systems of the pokeberry can reach 2 percent, the pokeberry has a large number of cadmium adsorption sites, and the adsorption sites of heavy metal of the pokeberry can be released through modification by diluted acid; the modified plant material is added into the tobacco extracting liquid and can adsorb the cadmium ions in the tobacco extracting liquid, and the possibility of adding non-plant components into the tobacco extracting liquid is avoided. The plant material adsorbent is simple in treatment process, easy to operate, low in cost and reusable.

The invention discloses a preparation method of a lead-arsenic-cadmium adsorption material. The method comprises the following steps of (1) drying and crushing rape straw, sieving and compacting the crushed rape straw, carrying out pyrolysis carbonization under an oxygen limiting condition or an oxygen-free condition, and performing cooling under an inert gas environment to obtain a material A; (2) drying and crushing tea leaf residues, mixing the crushed tea leaf residues with an iron salt solution, then performing aging, drying and compacting on the obtained mixture, carbonizing the mixtureunder the oxygen limiting condition or the oxygen-free condition, and cooling the mixture under an inert gas environment to obtain a material B; (3) mixing the material A with the material B to obtainthe lead-arsenic-cadmium adsorption material. The lead-arsenic-cadmium adsorption material prepared through the method can adsorb ions of heavy metal such as lead, arsenic and cadmium at the same time, the competitive adsorption is small, and the adsorption performance is excellent; meanwhile, the effective arsenic content of ammonium nitrate leached from soil can be reduced by 71% or above, theeffective cadmium content can be reduced by 66% or above, the effective lead content can be reduced by 72% or above, and the removal rate of lead, arsenic and cadmium is high at the same time.