CAJ | 학술논문

采用二氯甲烷超声波萃取，提取甲醇制烯烃（MTO）待生催化剂和不完全再生催化剂外表面可溶性积炭，采用氢氟酸溶解及碳酸钠溶液中和后再用二氯甲烷超声波萃取，提取待生催化剂和不完全再生催化剂孔道内可溶性积炭，结合气相色谱-质谱（GC-MS）分析了其组成，并对MTO催化剂积炭形成的机理和再生烧炭的机理进行了分析探讨。结果表明：MTO 待生催化剂外表面可溶性积炭主要是饱和烃和芳烃，其中饱和烃以C23～C31的正构烷烃为主，芳烃以一环和二环芳烃为主；孔道内可溶性积炭均为芳烃，以三环和四环芳烃为主，从质谱峰强度计算约占总量的80%，菲和芘约占总量的50%。MTO不完全再生催化剂外表面可溶性积炭主要是沸点较高的 C23～C31正构烷烃；孔道内可溶性积炭主要是几个高含量组分如芘和菲等的残留。在催化剂外表面的饱和烃可能是由小分子烯烃类化合物经过一系列聚合而成，而催化剂外表面的一环和二环芳烃应该是从分子筛孔道内形成并溢出，在分子筛孔道口吸附。分子筛催化剂孔道内的多环芳烃，是由小分子烃类化合物经过一系列低聚、氢转移、环化和脱氢等反应生成。
채용이록갑완초성파췌취，제취갑순제희경（MTO）대생최화제화불완전재생최화제외표면가용성적탄，채용경불산용해급탄산납용액중화후재용이록갑완초성파췌취，제취대생최화제화불완전재생최화제공도내가용성적탄，결합기상색보-질보（GC-MS）분석료기조성，병대MTO최화제적탄형성적궤리화재생소탄적궤리진행료분석탐토。결과표명：MTO 대생최화제외표면가용성적탄주요시포화경화방경，기중포화경이C23～C31적정구완경위주，방경이일배화이배방경위주；공도내가용성적탄균위방경，이삼배화사배방경위주，종질보봉강도계산약점총량적80%，비화비약점총량적50%。MTO불완전재생최화제외표면가용성적탄주요시비점교고적 C23～C31정구완경；공도내가용성적탄주요시궤개고함량조분여비화비등적잔류。재최화제외표면적포화경가능시유소분자희경류화합물경과일계렬취합이성，이최화제외표면적일배화이배방경응해시종분자사공도내형성병일출，재분자사공도구흡부。분자사최화제공도내적다배방경，시유소분자경류화합물경과일계렬저취、경전이、배화화탈경등반응생성。
The ultrasonic extraction technique with CH2Cl2 as solvent was introduced to extract the soluble coking deposited on external surface of zeolite pores in methanol to olefin (MTO) spent and partially regenerated catalyst. Then HF acid was used to dissolve the coking catalyst to release the internal coking, followed by neutralization with Na2CO3 solution and extraction with CH2Cl2, to extract the coking in the pores of zeolite in MTO spent and partially regenerated catalyst. The composition and distribution of the organic compounds were analyzed and identified by gas chromatgraphy-mass spectrometer(GC-MS), the mechanism of coking formation on MTO catalysts and the mechanism of regeneration were analyzed and discussed as well. The results showed that the soluble coking on external surface were mainly saturated hydrocarbons (nC23-nC31accounted for most part) and a small amount of aromatic hydrocarbons with one or two benzene rings. The soluble coking adsorbed in the zeolite pores mainly were aromatic hydrocarbons (3-4 benzene rings), which accounted for about 80% according to the peak intensity in GC-MS, phenanthrene and pyrene accounted for about 50% of the total. While for the MTO regenerated catalyst, the species adsorbed on external surface were mainly saturated hydrocarbons with high boiling points (nC23-n C31account for most part), and the species in zeolite pores were mainly the residual of high content coking, such as pyrene and phenanthrene. The saturated hydrocarbons on external surface of catalysts were derived from polymerization of small molecule olefins. The aromatic hydrocarbons with one or two benzene rings on external surface were formed in the zeolite pores, then spilled and adsorbed outside the pores. The aromatic hydrocarbons in the pores of zeolite were derived from a series of reactions, including oligomerization, hydrogen transfer, cyclization and dehydrogenation.