Small particle drug-eluting beads-transarterial chemoembolization combined with targeted therapy in the clinical treatment of unresectable liver cancer

BACKGROUND Liver cancer is a highly malignant tumor with significant clinical impact.Chemotherapy alone often yields suboptimal outcomes in both the short and long term,characterized by high rates of local recurrence and distant metastasis,leading to a poor long-term prognosis.AIM To evaluate the clinical efficacy of small particle drug-eluting beads-transarterial chemoembolization(DEB-TACE)combined with targeted therapy for the treatment of unresectable liver cancer.METHODS We analyzed clinical data from 74 patients with unresectable liver cancer admitted between January 2019 and December 2020.Based on the different treatment regimens administered,patients were divided into the control(36 patients receiving sorafenib alone)and joint(38 patients receiving small particle DEB-TACE combined with sorafenib)groups.We compared liver function indicators[alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),albumin(ALB)]and serum tumor markers[alpha fetoprotein(AFP)]before and after treatment in both groups.Short-term efficacy measures[complete response(CR),partial response,progression disease,stable disease,objective response rate(ORR),and disease control rate(DCR)]were assessed post-treatment.Long-term follow-up evaluated median overall survival(OS),progression-free survival(PFS),and adverse reaction rates between the two groups.RESULTS One month post-treatment,the joint group demonstrated significantly higher rates of CR,ORR,and DCR compared to the control group(P<0.05).Three days after treatment,the joint group showed elevated levels of ALT,AST,and TBIL but reduced levels of ALB and AFP compared to the control group(P<0.05).The median OS was 18 months for the control group and 25 months for the joint group,while the median PFS was 15 months for the control group and 22 months for the joint group,with significant differences observed(log-rank:χ2=7.824,6.861,respectively;P=0.005,0.009,respectively).The incidence of adverse reactions was not significantly different between the groups(P>0.05).CONCLUSION The combination of small particle DEB-TACE and sorafenib significantly improves both short-and long-term outcomes in the treatment of unresectable liver cancer while preserving liver function.

Conventional vs drug-eluting beads transarterial chemoembolization for hepatocellular carcinoma

Transarterial chemoembolization(TACE) is the current standard of therapy for patients with intermediatestage hepatocellular carcinoma(HCC) according to the Barcelona Clinic Liver Cancer classification. The concept of conventional TACE(cTACE) is the selective obstruction of tumor-feeding artery by injection of chemotherapeutic agents, leading to ischemic necrosis of the target tumor via cytotoxic and ischemic effects. Drugeluting beads(DEBs) have been imposed as novel drugdelivering agents for TACE, which allows for higher concentrations of drugs within the target tumor and lower systemic concentrations compared with cTACE. Despite the theoretical advantages of DEB-TACE, it is still controversial in clinical practice as to whether DEBTACE is superior to cTACE in regard to overall survival and treatment response. In this review article, we summarize the clinical efficacy and safety of DEB-TACE for patients with intermediate or advanced stage HCC in comparison with cTACE.

Transarterial chemoembolization with drug-eluting beads in hepatocellular carcinoma

Transarterial chemoembolization(TACE) is a widely used standard treatment for patients with hepatocellular carcinoma(HCC) who are not suitable candidates for curative treatments. The rationale for TACE is that intra-arterial chemotherapy using lipiodol and chemotherapeutic agents, followed by selective vascular embolization, results in a strong cytotoxic effect as well as ischemia(conventional TACE). Recently, drugeluting beads(DC Beads?) have been developed for transcatheter treatment of HCC to deliver higher doses of the chemotherapeutic agent and to prolong contact time with the tumor. DC Beads? can actively sequester doxorubicin hydrochloride from solution and release it in a controlled sustained fashion. Treatment with DC Beads? substantially reduced the amount of chemotherapeutic agent that reached the systemic circulation compared with conventional, lipiodol-based regimens, significantly reducing drug-related adverse events. In this article, we describe the treatment response, survival, and safety of TACE used with drugeluting beads for the treatment of HCC and discuss future therapeutic possibilities.

Advances in the treatment of hepatocellular carcinoma using drug-eluting beads

Hepatocellular carcinoma(HCC)is one of the most common types of malignant tumor.Although radical surgery and liver transplantation are possible cures for the disease,most patients are beyond the optimum stage for radical treatment at the time of diagnosis.Transarterial chemoembolization(TACE)is the first choice of treatment for advanced HCC.Owing to the widespread use of conventional TACE(cTACE),the problems with this treatment cannot be ignored.Drug-eluting beads(DEBs),a new type of embolization material,appear to overcome the problems of cTACE,and they have other advantages such as synchronous controlled continuous drug release after chemotherapy and embolization and low blood concentrations after treatment.This review summarizes the recent advances in the use of DEB-TACE to treat HCC.

Drug-eluting beads transarterial chemoembolization sequentially combined with radiofrequency ablation in the treatment of untreated and recurrent hepatocellular carcinoma

BACKGROUND Drug-eluting beads transarterial chemoem-bolization(DEB-TACE)has the advantages of slow and steady release,high local concentration,and low incidence of adverse drug reactions compared to the traditional TACE.DEBTACE combined with sequentially ultrasound-guided radiofrequency ablation(RFA)therapy has strong anti-cancer effects and little side effects,but there are fewer related long-term studies until now.AIM To explore the outcome of DEB-TACE sequentially combined with RFA for patients with primary hepatocellular carcinoma(HCC).METHODS Seventy-six patients with primary HCC who underwent DEB-TACE sequentially combined with RFA were recruited.Forty patients with untreated HCC were included in Group A,and 36 patients with recurrent HCC were included in Group B.In addition,40 patients with untreated HCC who were treated with hepatectomy were included in Group C.The serological examination,preoperative magnetic resonance imaging examination,and post-treatment computed tomography enhanced examination were performed for all patients.The efficacy was graded as complete remission(CR),partial remission(PR),stable disease and progressive disease at the 3rd,6th,and 9th.All patients were followed up for 3 years and their overall survival(OS),disease-free survival(DFS)were assessed.RESULTS The efficacy of Group A and Group C was similar(P>0.05),but the alanine aminotransferase,aspartate aminotransferase and total bilirubin of Group A were lower than those of Group C(all P<0.05).The proportions of CR(32.5%),PR(37.5%)were slightly higher than Group A(CR:27.5%,PR:35%),but the difference was not statistically significant(χ2=0.701,P=0.873).No operationalrelated deaths occurred in Group A and Group C.The OS(97.5%,84.7%,and 66.1%)and the DFS(75.0%,51.7%,and 35.4%)of Group A at the 1st,2nd,and 3rd year after treatment were similar with those of Group C(OS:90.0%,79.7%,and 63.8%;DFS:80.0%,59.7%,and 48.6%;P>0.05).The OS rates in Group A and Group B(90%,82.3%,and 66.4%)were similar(P>0.05).The DFS rates in Group B(50%,31.6%,and 17.2%)were lower than that of Group A(P=0.013).CONCLUSION The efficacy of DEA-TACE combined with RFA for untreated HCC is similar with hepatectomy.Patients with recurrent HCC could get a longer survival time through the combined treatment.

Efficacy of intra-arterial contrast-enhanced ultrasonography during transarterial chemoembolization with drug-eluting beads for hepatocellular carcinoma

AIM To assess the usefulness of intra-arterial contrastenhanced ultrasonography(IAUS) during transarterial chemoembolization(TACE) with drug-eluting beads(DEB) for hepatocellular carcinoma(HCC).METHODS Thirty two patients with 39 HCC underwent DEB-TACE guided with IAUS, and examined by contrast-enhanced ultrasonography(CEUS) or dynamic CT after DEB-TACE were enrolled in this study. CEUS findings before DEBTACE and IAUS findings were compared. Treatments judged to be complete and incomplete for lesions were appropriate and insufficient, respectively. Findings on CEUS and/or dynamic CT performed 1, 3 and 6 mo after DEB-TACE were evaluated using m RECIST(CR/PR/SD/PD).RESULTS The treatments were complete and incomplete in 26 and 13 lesions, respectively. On imaging evaluation using CEUS and/or dynamic CT one month after treatment, 25 and 1 lesions were judged to be CR and PR, respectively, and at 6 mo after treatment, the results were CR, PR, SD and PD for 24, 1, 0 and 1 of these lesions, respectively, in the 26 completely treated lesions. Of the 13 lesions in which treatment was incomplete, the results on imaging at one month after treatment were CR, PR, SD and PD for 0, 6, 4 and 3 lesions, respectively. The overall CR rate at 6 mo after treatment was 61.5%(24/39).CONCLUSION A combination of DEB-TACE with IAUS can improve the therapeutic effects in patients with HCC.

Use of Initial Modified RECIST Tumor Response Evaluation Criteria for Predicting Survival in Patients with Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization with Drug-Eluting Beads

Introduction: Transarterial chemoembolization (TACE) reduces tumor growth and increases survival in patients with hepatocellular carcinoma (HCC). Drug-eluting beads (DEB) deliver slow-release chemotherapy and reduce systemic toxicity during TACE. This study correlated initial tumor response according to modified RECIST (mRECIST) criteria and 1-year survival in patients with HCC treated with TACE-DEB, and identified predictors of tumor response. Methods: Fifty-two patients with HCC received TACE-DEB loaded with doxorubicin 75 mg during a 6-month period. Tumor response was evaluated 1 month after the procedure according to mRECIST criteria. Results: Most patients were cirrhotic and etiology of liver disease was hepatitis C in 26/52 (50%). Similar numbers of patients had Barcelona Clinic Liver Cancer (BCLC) A and BCLC B disease. Most patients had one nodule (66%). Complete response (CR) was achieved in 12/52 (23%), partial response in 19/52 (37%), stable disease in 4/52 (8%) and progressive disease in 17/52 (32%). Largest HCC ≤58 mm and BCLC stage A were associated with CR. The 1-year survival was 74%, with survival rates of 95% and 56% in the BCLC A and B groups, respectively. Variables reflecting tumor extension were associated with better survival. CR according to mRECIST criteria was a predictor of better 1-year survival (100% vs. 64%, P < 0.05). Conclusion: BCLC A and CR according to mRECIST criteria predict improved 1-year survival in patients with HCC treated with TACE-DEB. Further studies are needed to evaluate other predictors of survival and to determine if tumor response predicts long-term survival.

Extravascular use of drug-eluting beads: A promising approach in compartment-based tumor therapy

Intraperitoneal carcinomatosis(PC)may occur with several tumor entities.The prognosis of patients suffering from PC is usually poor.Present treatment depends on the cancer entity and includes systemic chemotherapy,radiation therapy,hormonal therapy and surgical resection.Only few patients may also benefit from hyperthermic intraperitoneal chemotherapy with a complete tumor remission.These therapies are often accompanied by severe systemic side-effects.One approach to reduce side effects is to target chemotherapeutic agents to the tumor with carrier devices.Promising experimental results have been achieved using drug-eluting beads(DEBs).A series of in vitro and in vitro experiments has been conducted to determine the suitability of their extravascular use.These encapsulation devices were able to harbor CYP2B1producing cells and to shield them from the hosts immune system when injected intratumorally.In this way ifosfamide-which is transformed into its active metabolites by CYP2B1-could be successfully targeted into pancreatic tumor growths.Furthermore DEBs can be used to target chemotherapeutics into the abdominal cavity for treatment of PC.If CYP2B1 producing cells are proven to be save for usage in man and if local toxic effects of chemotherapeutics can be controlled,DEBs will become promising tools in compartmentbased anticancer treatment.

Drug-eluting bead transarterial chemoembolization as neoadjuvant therapy pre-liver transplantation for advanced-stage hepatocellular carcinoma

BACKGROUND The objectives of this study were to assess the safety and efficacy of drug-eluting bead transarterial chemoembolization(DEB-TACE)as neoadjuvant therapy before liver transplantation(LT)for advanced-stage hepatocellular carcinoma(HCC)and to analyze the prognostic factors.AIM To determine whether DEB-TACE before LT is superior to LT for advanced-stage HCC.METHODS A total of 99 individuals diagnosed with advanced HCC were studied retrospectively.The participants were categorized into the following two groups based on whether they had received DEB-TACE before LT:DEB-TACE group(n=45)and control group(n=54).The participants were further divided into two subgroups based on the presence or absence of segmental portal vein tumor thrombus(PVTT).The DEB-TACE group consisted of two subgroups:Group A(n=31)without PVTT and group B(n=14)with PVTT.The control group also had two subgroups:Group C(n=37)without PVTT and group D(n=17)with PVTT.Data on patient demographics,disease characteristics,therapy response,and adverse events(AEs)were collected.The overall survival(OS)and recurrence-free survival(RFS)rates were assessed using Kaplan-Meier curves.Univariate and multivariate Cox regression analyses were conducted to determine the parameters that were independently related to OS and RFS.RESULTS The DEB-TACE group exhibited an overall response rate of 86.6%.Following therapy,there was a significant decrease in the median alpha-fetoprotein(AFP)level(275.1 ng/mL vs 41.7 ng/mL,P<0.001).The main AE was post-embolization syndrome.The 2-year rates of RFS and OS were significantly higher in the DEB-TACE group than in the control group(68.9%vs 38.9%,P=0.003;86.7%vs 63.0%,P=0.008).Within the subgroups,group A had higher 2-year rates of RFS and OS compared to group C(71.0%vs 45.9%,P=0.038;83.8%vs 62.2%,P=0.047).The 2-year RFS rate of group B was markedly superior to that of group D(64.3%vs 23.5%,P=0.002).Results from multivariate analyses showed that pre-LT DEB-TACE[hazard ratio(HR)=2.73,95%confidence interval(CI):1.44-5.14,P=0.04],overall target tumor diameter≤7 cm(HR=1.98,95%CI:1.05-3.75,P=0.035),and AFP level≤400 ng/mL(HR=2.34;95%CI:1.30-4.19,P=0.009)were significant risk factors for RFS.Additionally,pre-LT DEBTACE(HR=3.15,95%CI:1.43-6.96,P=0.004)was identified as a significant risk factor for OS.CONCLUSION DEB-TACE is a safe and efficient therapy for advanced-stage HCC and also enhances patient survival after LT.

Long-term outcomes of titanium-nitride-oxide coated stents and drug-eluting stents in acute coronary syndrome:A systematic review and meta-analysis

BACKGROUND In severe cases of coronary artery disease,percutaneous coronary intervention provide promising results.The stent used could be a drug-eluting stent(DES)or a titanium-nitride-oxide coated stent(TiNOS).AIM To compare the 5-year effectiveness and safety of the two stent types.METHODS The following systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines,and PubMed/MEDLINE,Scopus,and Cochrane Central were searched from inception till August 2023.Primary outcomes were major adverse cardiac events(MACE),cardiac death,myocardial infarction(MI),cardiac death or MI,and ischemia-driven total lesion revascularization(ID-TLR).RESULTS Four randomized controlled trials(RCT),which analyzed a sum total of 3045 patients with acute coronary syndrome(ACS)after a median follow-up time of 5 years were included.Though statistically insignificant,an increase in the ID-TLR was observed in patients receiving TiNOSs vs DESs.In addition,MI,cardiac death and MI,and definite stent thrombosis(DST)were significantly decreased in the TiNOS arm.Baseline analysis revealed no significant results with meta-regression presenting non-ST elevated MI(NSTEMI)as a statistically significant covariate in the outcome of MACE.CONCLUSION TiNOS was found to be superior to DES in terms of MI,cardiac death or MI,and DST outcomes,however,the effect of the two stent types on ID-TLR and MACE was not significant.A greater number of studies are required to establish an accurate comparison of patient outcomes in TiNOS and DES.

Prolonged dual antiplatelet therapy after drug-eluting stent implantation improves long-term prognosis for acute coronary syndrome:five-year results from a large cohort study

BACKGROUND:To investigate the most appropriate dual antiplatelet therapy(DAPT)duration for patients with acute coronary syndrome(ACS)after drug-eluting stent(DES)implantation in the largest cardiovascular center of China.METHODS:We enrolled 5,187 consecutive patients with ACS who received DES from January to December 2013.Patients were divided into four groups based on DAPT duration:standard DAPT group(11-13 months,n=1,568)and prolonged DAPT groups(13-18 months[n=308],18-24 months[n=2,125],and>24 months[n=1,186]).Baseline characteristics and 5-year clinical outcomes were recorded.RESULTS:Baseline characteristics were similar across the four groups.Among the four groups,those with prolonged DAPT(18-24 months)had the lowest incidence of major adverse cardiovascular and cerebrovascular events(MACCEs)(14.1%vs.11.7%vs.9.6%vs.24.2%,P<0.001),all-cause death(4.8%vs.3.9%vs.2.1%vs.2.6%,P<0.001),cardiac death(3.1%vs.2.6%vs.1.4%vs.1.9%,P=0.004),and myocardial infarction(MI)(3.8%vs.4.2%vs.2.5%vs.5.8%,P<0.001).The incidence of bleeding was not different among the four groups(9.9%vs.9.4%vs.11.0%vs.9.4%,P=0.449).Cox multivariable analysis showed that prolonged DAPT(18-24 months)was an independent protective factor for MACCEs(hazard ratio[HR]0.802,95%confidence interval[CI]0.729-0.882,P<0.001),all-cause death(HR 0.660,95%CI 0.547-0.795,P<0.001),cardiac death(HR 0.663,95%CI 0.526-0.835,P<0.001),MI(HR 0.796,95%CI 0.662-0.957,P=0.015),and target vessel revascularization(HR 0.867,95%CI 0.755-0.996,P=0.044).Subgroup analysis for high bleeding risk showed that prolonged DAPT remained an independent protective factor for all-cause death and MACCEs.CONCLUSION:For patients with ACS after DES,appropriately prolonging the DAPT duration may be associated with a reduced risk of adverse ischemic events without increasing the bleeding risk.

Conventional versus drug-eluting bead transarterial chemoembolization:A better option for treatment of unresectable hepatocellular carcinoma

Transarterial chemoembolization(TACE) is a minimally invasive procedure involving intra-arterial catheter-based chemotherapy to selectively administer high doses of cytotoxic drugs to the tumor bed along with ischemic necrosis induced by arterial embolization.Chemoembolization forms the essential core of management in patients with hepatocellular carcinoma(HCC) who are not suitable for curative therapies such as transplantation,resection,or percutaneous ablation.TACE of hepatic cancer(s) has proven to be helpful in achieving local tumor control,and has supported the ability to prevent tumor progression,prolong patient life,and manage patient symptoms.Recent data have demonstrated that,in patients with single-nodule HCC ≤3 cm without vascular invasion,the 5-year overall survival with TACE was found to be comparable with hepatic resection and radiofrequency ablation.Used for several years,Lipiodol continues to play a vital role as a tumor-seeking and radiopaque drug delivery vector in interventional oncology.Efforts have been made to enhance the administration of chemotherapeutic agents to tumors.Compared with conventional TACE,drug-eluting bead TACE is a fairly new drug delivery embolization technique that permits fixed dosing and has the ability to provide sustained release of anticancer agents over a period of time.The present review discusses the basic procedure of TACE and its properties,and the effectiveness of conventional and drug-eluting bead chemoembolization systems currently available or presently undergoing clinical evaluation.

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND Percutaneous drug-eluting stent implantation(DESI)is an emerging and promising treatment modality for infrapopliteal artery diseases(IPADs).This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio(HR),which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.AIM To explore the superiority of drug-eluting stents(DESs)vs traditional treatment modalities for IPADs.METHODS The following postoperative indicators were the outcomes of interest:All-cause death(ACD)-free survival,major amputation(MA)-free survival,target lesion revascularization(TLR)-free survival,adverse event(AE)-free survival,and primary patency(PP)survival.The outcome measures were then compared according to their respective HRs with 95%confidence intervals(CIs).The participants were human IPAD patients who underwent treatments for infrapopliteal lesions.DESI was set as the intervention arm,and traditional percutaneous transluminal angioplasty(PTA)with or without bare metal stent implantation(BMSI)was set as the control arm.A systematic search in the Excerpta Medica Database(Embase),PubMed,Web of Science,and Cochrane Library was performed on November 29,2022.All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included.When studies did not directly report the HRs but gave a corresponding survival curve,we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs.Then,meta-analyses were conducted using a random-effects model.RESULTS Five randomized controlled trials and three cohort studies involving 2639 participants were included.The ACDfree and MA-free survival HR values for DESI were not statistically significant from those of the control treatment(P>0.05);however,the HR values for TLR-free,AE-free,and PP-survival differed significantly[2.65(95%CI:1.56-4.50),1.57(95%CI:1.23-2.01),and 5.67(95%CI:3.56-9.03),respectively].CONCLUSION Compared with traditional treatment modalities(i.e.,PTA with or without BMSI),DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Fabrication of Core-Shell Hydrogel Bead Based on Sodium Alginate and Chitosan for Methylene Blue Adsorption

A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calcium ions(Ca^(2+)).The shell,composed of a chitosan/activated carbon mixture,was then coated onto the core.Fourier transform infrared spectroscopy confirmed the grafting polymerization of acrylamide onto sodium alginate.Scanning electron microscopy images showed the core-shell structure.The core exhibited a high water uptake ratio,facilitating the diffusion of methylene blue into the core.During the diffusion process,the methylene blue was first adsorbed by the shell and then further adsorbed by the core.Adsorption tests showed that the coreshell structure had a larger adsorption capacity than the core alone.The shell effectively enhanced the adsorption capacity to methylene blue compared to the single core.Methylene blue was adsorbed by activated carbon and chitosan in the shell,and the residual methylene blue diffused into the core and was further adsorbed.

H_4SiW_(12)O_(40)/TiO_2/beads光催化降解亚甲基蓝的研究

以钛酸四丁酯为原料,空心微珠为载体,采用溶胶-凝胶法制备TiO2/beads光催化剂载体,然后浸渍法制备出H4SiW12O40/TiO2/beads表面负载修饰型复合光催化剂,并运用SEM、XRD、FT-IR和DRS对催化剂进行表征和分析。研究了H4SiW12O40/TiO2/beads对亚甲基蓝降解的光催化活性,考察了光强度、pH值、曝气量、底物浓度和催化剂用量等对催化效率的影响。实验结果表明,在中性条件下,H4SiW12O40/TiO2/beads催化剂的投加量为0.25 g/L,浓度为7.5 mg/L的亚甲基蓝溶液在250 W的紫外灯和600 W的可见光灯下光照60 min降解率分别可达到94.5%和55%。

溶胶-凝胶法制备TiO_2·SiO_2/beads及其光催化性能的研究

研究以四异丙醇钛 [Ti (iso OC3 H7) 4 ]、硅酸乙酯为原料 ,以空心玻璃微球为载体 ,用溶胶 凝胶法制备可漂浮附载型复合光催化剂TiO2 ·SiO2 /beads的过程 ,利用附载型复合光催化剂降解有机磷农药。结果表明 :附载型复合光催化剂活性显著提高 ,牢固性增强 ,TiO2 ·SiO2 摩尔比存在最佳值。n (TiO2 ) /m (SiO2 ) =30 / 70时 ,光催化剂活性最高 ,其活性是同样降解条件下 ,同样含量DegussaP 2 5TiO2 的

TiO_2·SiO_2/beads降解有机磷农药的研究

研究以四氯化钛 ,硅酸乙酯为原料 ,以空心玻璃微球为载体 ,用浸涂法制备TiO2 ·SiO2 /beads负载型复合光催化剂的过程。对利用负载型复合光催化剂降解有机磷农药进行了活性评价。结果表明 :TiO2 ·SiO2 /beads光活性显著提高 ,最佳光催化剂活性是同样降解条件下、同样含量的DegussaP - 2 5TiO2 光活性的 1.35倍左右。另外 ,对TiO2 ·SiO2 /beads的吸附性和比表面进行测试 ,同时从微观角度对负载型复合光催化剂的表面状态和光催化剂颗粒尺寸进行分析。

附载型复合光催化剂TiO_2·SiO_2/beads降解有机磷农药

研究以四异丙醇钛 [Ti( iso- O C3 H7) 4]、硅酸乙酯为原料 ,以空心玻璃微球为载体 ,用溶胶—凝胶法制备可漂浮附载型复合光催化剂 Ti O2 · Si O2 / beads的过程 ,利用附载型复合光催化剂降解有机磷农药。结果表明 ,复合型光催化剂 Ti O2 · Si O2 摩尔比存在最佳值 ,n ( Ti O2 ) / m ( Si O2 ) =30 / 70时 ,光催化剂活性最高 ,其活性是同样降解条件下、同样含量 Degussa P- 2 5Ti O2 的 2倍左右。该光催化剂比表面大 ,吸附性强。并用 XRD和

TiO_2·SiO_2/beads的制备与性质

研究以空心玻璃微球为载体 ,用Sol gel法制备附载型复合光催化剂的过程 ,并对TiO2 ·SiO2 /beads光催化活性进行评价 .结果表明 :复合型光催化剂TiO2 ·SiO2 摩尔比存在最佳值 ,当n(TiO2 ) /m(SiO2 ) =30 /70时 ,光活性是在同样降解条件下 ,同样含量DegussaP 2 5TiO2 的 2倍左右 .同时研究制备方法、制备条件、TiO2 ·SiO2 摩尔比、TiO2 ·SiO2 /beads吸附性、活化条件、比表面等因素对附载型复合光催化剂活性的影响 .

CoPcS/TiO_2/beads及TiO_2/beads光催化降解水面漂浮植物油

以钛酸四丁酯为原料,以空心玻璃微珠为载体,采用溶胶-凝胶法制备出TiO2/beads光催化剂,用浸渍法制备出CoPcS/TiO2/beads光催化剂。研究了TiO2/beads及CoPcS/TiO2/beads光催化降解水面漂浮植物油的最优条件。结果表明,酸性或中性条件下,375 W中压汞灯照射2～3 h,TiO2/beads与CoPcS/TiO2/beads的投加量分别为3 g与1 g时,植物油的去除率达90%以上,投加微量的H2O2,可大大提高两者的光催化去除率。